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Pod Med Test 2
Terms in this set (362)
What are adnexa?
Nails and hair, sebaceous glands and piliary complexes
How many layers is the dorsum of the foot?
Less than 10 layers of cells, thick with hair follicles
What are the characteristics of the plantar surface of the foot?
-Thick, cornified and hairless
-There are large numbers of eccrine sweat glands
-Weight bearing areas may have a ten-fold increase in thickness compared to dorsal skin
-Skin variations occur in relation to age, race and sex
What are the layers of the skin?
-Epidermis - arises from ectoderm
-Dermis - arises from mesoderm
-Vascular elements, the subcutis and connective tissue stroma arise from neural ectoderm
-Adnexa arise from an ectodermal-mesodermal interaction which results in modulation of the basal cells in the stratum germinativum
What is the principle cell of the epidermis from ectodermal origin?
What is the function of the keratinocytes?
Produces keratin, also plays a role in immune function of the skin
What is the normal transit time of keratinocytes from the basement membrane to the outer cornified layer?
24 to 42 days (average is 27-30 days)
What is a horn cell?
Keratinocyte initial differentiation that accumulates intermediate filaments or "tonofilaments"
What are tonofilaments?
Fibrous alpha helical patterned proteins that make up the cytoskeleton of the cell
What do tonofilaments attach to?
Desmosomes (specialize in cell-to-cell communications and adhesion)
Defects in tonofilaments will causes what inherited diseases?
Darier disease, striate palmoplantar keratoderma and Hailey-Hailey (benign familial pemphigus) disease
What do keratinocytes secrete?
IL-1 (stimulates growth and action of immune cells)
Epidermal-cell-derived thymocyte activating factor (T cell chemoattractant and activation)
What is a protein? within the extracellular matrix which helps to provide motility for the keratinocytes
Fibronectin (produced by fibroblasts and modified by keratinocytes)
What are the anchoring fibrils and intracellular connection components and their functions?
Desmosomes- cell to cell attachment for keratinocytes (cadherin family)
Hemidesmosomes- basal keratinocyte connection to basement membrane zone (integrin family)
Gap junctions- intracellular communications (connexin protein channels)
What are the four layers of the skin?
What distinguishes the layers of the skin?
The changing appearances of the keratinocytes
Where are the horny layers of the skin the thickest?
Palms and soles
What is the stratum malpighii?
Refers to the stratum basalis, spinosum and granulosum - that is all the cells of the epidermis containing nuclei
What is the deepest layer of the skin?
Stratum basalis- 50% of cells remain here
What layer of skin begins to show signs of specialization?
Stratum spinosum- keratinohyline granules develop in the upper levels
What contributes to the adhesiveness of the cornified layer?
Keratin filament system and keratohyline granules
What do the keratohyline granules become?
Filaggrin (an intermediate filament associated protein and is believed to facilitate keratin filament aggregation and major component of the stratum corneum)
What is decreased in patients with atopic dermatitis?
What is increased in patients with atopic dermatits?
Additional proteins, involucrin, cystatin A and Ted-H-1 antigen
What layer of skin provides a protective barrier?
What two components make up the stratum corneum?
Stacked, polyhedral, anucleated keratinocytes
Lamellar-lipid rich matrix
What is the pattern of cells in the stratum corneum?
Basket weaved "interdigititated"
What are the functions of the stratum corneum?
-Retards water loss through evaporation
-Guards against mechanical insults
-Provides a protective barrier against microorganisms
-Screens out more than 80% of UVB radiation
What layer is referred to as the Brick and Mortor System?
What makes up the cornified envelop (contains the keratinocytes)
Involucrin (attaches to the lamellar membranes) and loricrin (predominant protein)
An insertion mutation in what protein causes keratoderma and ichythiosis (also contributes to Vohwinkel's keratoderma)?
What makes up the lamellar membrane?
Ceramides, cholesterol, free fatty acids, and cornedesmosomes
What is Psoriasis?
-Keratinocytes demonstrate an abnormally fast transition rate through the skin, taking only three to four days
-The result is poorly adhesed keratin and nucleated cells in the stratum corneum
-Some of the blistering diseases result from disruption of the desmosomal attachments at the basement membrane zone
What results from the loss of cohesion of the keratinocytes?
Acantholysis (desmosomal disruption, leading to cell separation)
What is psoriasis secondary to?
Circulating antibodies directed at the desmosomal attachments
What is acanthosis?
Increased thickness of the stratum spinosum
What is spongiosis?
The presence of edema within the stratum spinosum
What is parakeratosis?
The presence of nucleated keratinocytes within the stratum corneum
What is the melanocyte derived from?
What type of cell is a melanocyte?
What is the job of the melanocyte?
Melanin/Pigment factory (can supply 36 keratinocytes with pigments)
What are the two pigments the melanocyte produces?
-Eumelanin which is a brown to black pigment
-Phaeomelanin which is yellow to red
What happens in Vitiligo?
The skin becomes white due to the destruction of melanocytes (T lymphocyte activation)
What is wrong in albinism?
The melanocytes cannot make melanosomes
Why can hyperpigmentation occur during pregnancy?
The melanocyte possesses receptor sites for ACTH, estrogen, progesterone and melanin stimulating hormone
Langerhan cells are in what group of cells?
What is the job of Langerhan cells?
Immune response and mediate delayed hypersensitivity reactions, make IL-1, play a role in graft rejection (like keratinocytes) and immuno-surveillance
What lineage is the Langerhan cell?
Monocyte/macrophage and bone marrow
What are the two stages of a Langerhan cell?
-Sentinels: can ingest particulates and process antigens efficiently, but are weak stimulators of unprimed T cells
-Messengers: migrate to lymph nodes after contact with antigens and stimulate T cells
Depletion of Lagnerhan cells (UV exposure) can lead to what?
What is histiocytosis-X?
A disease process characterized by deranged Langerhans cells
What is the function of the basement membrane?
It serves as a structural support to keep the dermis and epidermis together (semi-permeable filter)
What is affected in Bullous diseases?
The basement membrane (epidermal separation)
What are the three layers of the basement membrane?
1) Lamina Lucida
2) Lamina Densa
3) Reticular Layer
Where is the lamina lucida?
directly beneath the stratum basalis
What is the lamina dense?
Collagen 4 layer that gives the basement membrane strength (under lamina lucida)
What is the reticular layer?
Contains anchoring filaments made of Collage 7
What is the purpose of hemidesmosomes?
To attach keratinocytes to the basement membrane
Characteristics of the dermis
1) Composed of CT- collagen, elastic, and reticular fibers
2) Primary cell is fibroblast, but also has mast cells
3) Mesodermal origin
4) Has 2 layers: pars papillaris and pars reticularis
What is the job of fibroblasts?
To make fibers (collagen, elastic, and reticulum)
What is the primary component of the dermis?
What is the major stress resistant material of the skin?
How do reticular fibers compare to collagen fibers?
Chemically similar but reticular fibers are smaller
Where are reticular fibers most found?
In the upper portion of the papillar dermis
What do reticular fibers do?
Anchoring fibrils for the basal lamina
Elastic fibers are structurally and chemically _____ from collagen
Where are elastic fibers found?
These fibers are present in both levels of the dermis being quite thin in the papillary dermis but coarse in the reticular dermis
What makes up the ground matrix of the dermis?
Mucopolysaccharides (essentially hyaluronic acid, chondroitin sulfate, dermatan sulfate, neutral mucopolysaccharides and electrolytes)
What is the pars papillaris?
Thin, haphazardly arranged layer of collagen of the dermis
What structures are in the pars papillaris?
•Merkel cells - there are pleuri-potential cells which may be come neuro-exocrine, possess granules and may be involved in the mediation of touch sensations
•Meissner corpuscles - these are nerves that exist within the dermal papillae - particularly on the palms and soles these mediate touch and pressure
•Vater-Pacini corpuscles - these are located within the deeper portions of the dermis of weight-bearing surfaces - these mediate touch and pressure
•Unmyelinated nerve fibers which terminate in the papillary dermis transmit temperature, pain and itch
What is the pars reticularis?
Thick layer of collagen in the dermis with many elastic fibers, arranged parallel to the surface of the skin
What cells are present in the pars reticularis?
Histiocytes, mast cells (around blood vessels)
What is the Arrector pilorum?
SM attached to hair follicles
What is leiomyomas?
Tumors in the arrector pilorum
What receptors are present on mast cells?
What is contained in the granules of mast cells?
Heparin, histamine, SRS-A and other chemical mediators of the hypersensitivity response
What are glomus bodies?
-Specialized aggregates of smooth muscle cells between arterioles and venules
-They act to shunt blood from the arterial to the venous side of the vascular system and are best developed in the digits
What is the adnexa?
-The adnexa are comprised of the eccrine and apocrine glands and ducts as well at the pilosebaceous units
-Ectodermal in origin
What are the immunological defenses of the skin?
1) Tightly packed epidermis
2) Rapid turnover of cells
3) Low pH and water content
What is a primary skin lesion?
Develop from a pathology in the skin
-have not undergone natural evolution of the lesion and have not changed by manipulation
What are secondary skin lesions?
Evolve because of physical, chemical, or biological stimuli
What are the primary skin lesions?
What are the secondary skin lesions?
3) Fissure (arises from a break in the epidermis)
4) Erosion (arises from a break in the epidermis)
5) Ulcer (arises from a break in the epidermis)
6) Scar (arises from a break in the epidermis)
7) Lichenifications (arises from a break in the epidermis)
What is a Macule?
A circumscribed area of change in normal skin color without elevation or depression of the surface relative to the surrounding skin
• they are generally less than one centimeter in diameter
• they are flat and cannot be palpated
• an example of this would be a freckle
What is a patch?
Similar to a macule but a larger area is involved.
• they are greater than one centimeter in diameter
• an example of this would be vitiligo
What is a papule?
A solid elevated lesion less than 1 centimeter in diameter - most of which is above the plane of the surrounding skin. These lesions contain no free fluid or exudate. An example of this would be a verruca, dermatofibroma or lichen planus.
What is a plaque?
An elevation above the skin surface that occupies a relatively large surface area in comparison with its height above the skin. An example of this would be psoriasis
What is a lichenification?
A thickening of the epidermis resulting from repeated rubbing. An example of this would be lichen simplex chronicus
What is a nodule?
A palpable solid round or ellipsoidal lesion deeper and larger thana papule. It is similar to a papule,larger than one centimeter in diameter and again, contains no exudative or serous fluid. An example would be erythema nodosum
What is a wheal?
A rounded or flat topped elevation of the skin that is characteristically evanescent, disappearing within hours, as in urticaria associated with allergy
What is a vesicle?
A circumscribed elevated lesion that contains fluid. An example of this would be herpes zoster
What is a bulla?
A circumscribed, elevated, fluid filled lesion, greater than one centimeter. It may be uni- or multilocular in nature. An example could be as common as a friction blister or as rare as bullous pemphigoid or pemphigus
What is a pustule?
A circumscribed elevation of skin that contains purulent exudate such as an abscess
What is a scale?
Excess accumulation of cornified tissue on the skin surface. It will often follow inflammation or a drug eruption. The scales can vary as in the white scales common in psoriasis to large scales seen in scarlet fever
What is a crust?
Dried exudate resulting from rupture, oozing or drying of a primary lesion. It can be yellow, honey, red or dark brown in color depending on the content of the dried exudate
What is a fissue?
A linear break in the epidermis. It can occur commonly in the interdigital web space secondary to maceration or along the heel margins where hyperkeratosis and xerosis exist concomitantly
What is an erosion?
A shallow, scooped out lesion penetrating the epidermis only. Again, this occurs secondary to maceration or friction
What is an ulcer?
A deep lesion penetrating to or through the dermil (full thickness epidermal loss)
What is a scar?
A permanent change in the skin following damage to the dermal layer. It is an irreversible skin change.
What are lichenifications?
Thickenings of the skin with accentuation of the skin lines. It will usually occur in the area of chronic irritation from rubbing or scratching. It can occur secondary to venous stasis or chronic edema and in later stages may appear almost moss-like or bark-like.
What are the special skin lesions?
What are comedones?
Sebaceous material which collects at the base of a hair follicle or sebaceous duct. Exposure to air causes oxidation and the characteristic 'black-head" appearance of the lesion
What is a milia?
Sebaceous material at the base of a hair follicle covered by a cap of skin. No oxidation occurs and is referred to as a "white-head."
What is a xanthoma?
A nodule -usually yellowish in color - containing fatty tissue.
What is maceration?
Thickening and whitening of the cornified layer of epidermal skin secondary to increased moisture
What is atrophy?
Loss of normal tissue mass with little or no replacement. It is frequently a result of aging but can be seen with injury and nutritional deficiencies
What is a striae?
A linear stretch mark occurring when the skin has been stretched and loses its elasticity.
What is alopecia?
hair loss which may or may not be permanent depending on the etiologic factor. Alopecia areata - circumscribed baldness; alopecia universalis - loss of all body hair
What is petechiae?
Minute hemorrhagic lesions secondary to rupture of superficial blood vessels and the extravasation of the hemoglobin breakdown products
What is ecchymosis?
Hemorrhage into the skin secondary to the rupture of blood vessels. Blood and its subsequent breakdown products are pooled within the tissue itself
What are excoriations?
Self-inflicted skin lesions, frequently seen from scratching a pruritic lesion. It is generally linear in nature.
What are configurations?
Both primary and secondary lesions will appear in configurations. This refers to the actual shape and arrangement of the lesions. Configurations are generally descriptive. Examples are linear, serpiginous, zosteriform, retiform, annular, and verrucous.
What are the aspects of examining a dermatological lesion?
1) Distribution of the mesion (where, how many, B/L?)
2) Evolution of the lesion (speed of development, progression, polymorphic?)
3) Involution of the lesion (how did it resolve?)
4) Grouping of the lesions (shapes)
5) Configurations of the lesions (designs)
7) Consistency (moveable, does it blanch, fluctuant, indurated?)
What is the most common skin derangement?
The corn or callus (hyperkeratinized skin)
What layer is thickened in a corn or callus?
Malpighian layer (stratum corneum and stratum spinosum)
What is acanthosis?
Thickening of the stratum spinosum secondary to increased cell numbers
What is the change at the basement membrane in a callus?
The number of rete pegs decreases. Their length, however, increases up to three-fold.
What is parakeratisos?
Nucleated cells in the stratum corneum (secondary to increased pressure, stimulating mitotic divisions)
What is the most common example of parakeratisos?
What are corns referred to as?
Waht are calluses referred to as?
What is a Heloma Durum?
A Hard Corn
What causes a heloma durum?
Secondary to mechanical stress from overlying foot coverage against bony prominences (hammer tones, mallet toes, adductovarus toes)
What is a distal clavi?
A heloma durum occurring at the distal pulp of a mallet toe
What is a heloma molle?
Soft corn between the toes (rubbery because of the excess moisture)
What causes a heloma molle?
Mechanical irritation between the head of the fifth proximal phalanx and the base of the fourth proximal phalanx
What is a heloma miliare?
Seed corn on the nonweight-bearing surface of the foot
What are heloma miliares associated with?
Anhydrosis or xerosis of the plantar tissue
True or false: heloma miliare can coalesce into larger lesions?
What is a heloma vasculaire?
A more sever sub-type of heloma durum. Because of increased pressure points - believed to be secondary to an actual "pinching" force - hemorrhagic extravasations occur from the papillae at the dermal-epidermal junction
What is a heloma neurofibrosum?
The pars papillaris thickens to the extent that its capillary plexus is present within the central core of the lesion
What is a tylomata?
This term generally infers a hyperkeratotic lesion on the plantar aspect of the foot
What are the classically accepted etiologies of plantar keratomas?
1. An abnormal metatarsal parabola resulting in a relatively longer or shorter metatarsal
2. Hypertrophied plantar condyles (the lateral condyle anatomically is larger and often slightly more plantar than the medial condyle)
3. Plantarflexed metatarsal secondary to retrograde forces from a contracted digit
4. Increased metatarsal declination angle
5. Mechanical secondary to abnormal foot function
What is the metatarsal break?
An angle formed by drawing an obliquely, laterally sloping line connecting the heads of metatarsals two through five compared to the long axis of the foot
What is the average metatarsal break angle?
How does a long metatarsal cause a callus?
It weight-bears early in the propulsion cycle and takes an abnormal amount of weight
What is the most common etiology of a plantarly prominent metatarsal?
It metatarsal is secondary to retrograde pressure created by a contracted digit (drives the metatarsal plantigrade, increasing pressure and causing a callus- most common in 2nd digit)
What is a Frieberg's infraction?
An avascular, aseptic osteonecrosis of the metatarsal head, occurring most commonly in the second metatarsal (hypertrophed plantar condyle)
What is the most common etiology of a hyopertrophed plantar condyle?
What bmx motion is most common to causing a callus?
Pronation, ligamentous laxity or a cavus foot
What bmx issue creates the greatest pathology?
Pronatory forces on an unstable foot
When do lesions plantar to the first metarsal occur most?
In a foot compensation that results in supination of the longitudinal midtarsal joint and maximum dorsiflexion of the first metatarsal
What pathology often accompanies lesions plantar to the first metarsal?
What are the reasons for a lesion plantar to the second metatarsal?
1) Retrograde pressure from a second digit hammer toe (long 2nd digit)
2) Abnormal metatarsal parabola
3) Hypermobility of the first ray (weight transferred to the second ray)
What are the least frequent plantar lesions?
Plantar to the 3rd metatarsal
What causes 3rd metatarsal plantar lesions?
•An abnormal metatarsal parabola
•Metatarsus adductus where the normal weight bearing load distribution is shifted more laterally
•Excessive longitudinal midtarsal joint supination
What causes plantar lesions under the 4th metatarsal?
-A pronatory compensation algorithm where the oblique midtarsal joint remains maximally pronated as the foot goes into propulsion
-Can also be elevated 5th ray
What causes plantar lesions under the 5th metatarsal?
-May occur with excessive pronation of the fifth metatarsal and/or the oblique midtarsal joint
-They occur when the fifth ray cannot dorsiflex and evert above the level of the other metatarsals
Why do medial hallux IPJ and first MPJ lesions occur?
Lesions occur most often when the foot compensation algorithm results in maximum pronation of both the subtalar and midtarsal joints AND these maximally pronated positions do not fully compensate the deformity (weight is transferred medially during propulsion because of abduction of the foot)
What is the most prominent autoimmune disease in humans?
What are the distributions of lesions in psoriasis?
• Predilection for the scalp (affects approximately 50% of patients), nails, extensor surfaces, elbows, knees and sacral region
• Usually symmetrical bilaterally
• Pruritis and burning may be present
What is the etiology for psoriasis?
Etiology unknown but a multi-factorial inheritance pattern is suspected (genetics and immune response play an important role)
What are the characteristics of lesions in psoriasis?
• Rounded, circumscribed, erythematous, scaling patches of various sizes
• Covered by grayish white or silvery white, imbricated and lamellar scales
• Nummular or coin-sized lesions are common
• Scales are micaceous and are looser toward the periphery, they are adherent in the center
What is an Auspitz's sign?
Removal of the psoriasis scale causes pin-point bleeding
What do 40% of psoriasis have?
What cell causes psoriasis?
T cells (hyperproliferation and faulty differentiation of keratinocytes play an important role)
What HLA is associated with early-onset psoriasis?
What HLA is associated with psoriatic arthritis?
HLA-B7 and HLA-B27
What HLA is associated with psoriasis and psoriatic arthritis?
What does increased T cell activity increase?
Tumor necrosis factor alpha
Interleukin 1β (IL-1β ) and 10 (IL-10)
What is the histology of psoriasis?
Lengthening of the dermal-epidermal folds occurs and capillary loops become somewhat dilated and tortuous resulting in the blood vessels of the dermis lying much closer to the adjacent hyperkeratotic surface
What are Munro's abscesses?
Polymorphonuclear leukocyte microabscesses commonly appear under the hyperkeratosis within the stratum corneum in psoriasis
What is the most common form of psoriasis?
Plaque-type or psoriasis vulgaris (75-80%)
What is characteristic of plaque-type or psoriasis vulgaris?
-A well-demarcated plaque greater than 1 cm in diameter lesions generally overlie bony prominences and are generally symmetric - a hallmark of plaque-type psoriasis
-Recurs, persists, Auspitz's sign, can be secondary to minor trauma
What is Guttate psoriasis (18%)?
• Round erythematous lesions (small 0.1-1cm lesions, Strep infection precedes)
• More common in children and young adults
What is pustular psoriasis (1.7%)?
Characterized by sterile pustules either generalized or focally located on the palms and soles
What is pustular psoriasis characterized by (general von Zumbusch type)?
-Severe,sometimes fatal presentation characterized byfiery-red patches studded may 1-2mm in diameter pustules
-Iodides, salicylates, cessation of glucocorticoid treatment, pregnancy, hypocalcemia infection - all may serve as triggers for an acute flare-up
-Patients are usually quite ill with leukocytosis, fever, hypocalcemia and hypoalbuminemia
What are the characteristics of a local pustular psoriasis?
• Affects the palms and soles often the thenar and hypothenar eminences and/or the instep or side of heel
• Iodides and salicylates may trigger an episode
What is erythodermis psoriasis?
-Inflammatory skin eruption that involves nearly all of the body surface
-May have areas of sterile pustules and may occur simultaneously with psoriatic arthritis
What is erythodermis psoriasis precipitated by?
Often precipitated by systemic illnesses, emotional stresses and alcoholism
What are patients with erythodermis psoriasis susceptible to?
What are the unique clinical characteristics of psoriasis?
•Koebner reaction (isomorphic response) - appearance of typical lesions a sites of even trivial injury
•Auspitz sign - pinpoint bleeding when a psoratic scale is forcibly removed. It occurs because of the severe thinning of the epidermis over the tips of the dermal papillae
•Woronoff ring - concentric blanching of the erythematous skin at or near the periphery of a healing psoriatic plaque
What are the podiatric manifestations of psoriasis?
-Symmetrical, chronic and recurrent eruption of the palms an soles (may be palms and soles exclusively)
-This type of psoriasis is extremely resistant to treatment which would normally be effective in other areas of the body. PUVA, intralesional steroids, etretinate, methotrexate, cyclosporine and occasionally dapsone may be helpful (lakes of pus from fused pustules)
What are the characteristics nail changes of psoriasis?
•Numerous pits 1 mm or so in diameter, similar to dents made with the tip of a ball point pen
• Presence of tan oval spots 2 to 4 mm in diameter - "oil spots"
• Heaped-up crusts accumulated beneath the free nail edges may become secondarily infected with Candida albicans
What are the five clinical patterns of psoriatic arthritis?
1) Asymmetrical distal interphalangeal joint involvement with nail damage (16%)
2) Arthritis mutilans with osteolysis of the phalangeal and metacarpals (5%)
3) Symmetric polyarthritis (15%)
4) Oligoarthritis with swelling and tenosynovitis of one or a few hand joints (70%)
5) Ankylosing spondylitis alone or with peripheral arthritis (5%)
What are the radiographic findings in ankylosing spondylitis alone or with peripheral arthritis?
-Similar to RA
•tapering or "whittling" of the phalanges
•"cupping" of proximal ends of the phalanges that results in telescoping of the involved digit
•osteolysis of the metatarsals
•destructive changes have a predilection for the distal and proximal interphalangeal joints with relative sparing of the metatarsal phalangeal joints
What is symmetric polyarthritis like?
RA with claw hands
What are the characteristics of symmetric arthritis?
•This will generally affect the small joints of the hands and feet, wrists, ankles, knees and elbows
•There is a high frequency of DIP joint involvement and a tendency for ankylosis of the DIP and PIP joints
•This digital involvement will lead to a "claw" or "paddle" deformity of the hands
What psoriatic arthitis is the most common and what joints does it affect?
-Oligoarthritis with swelling and tenosynovitis of one or a few hand joints
-Affects one larger joint and one or two IPJs (distal is characteristic)
How do you treat psoriatic arthritis?
-Rest, splinting, passive motion
-Utilization of non-steroidal anti-inflammatory agents (aspirin and indomethacin may be effective)
-Intramuscular corticosteroid injection may be useful
-Topical treatment recommended when less than 20% of the area is covered (tar preparations, topical corticosteroids, topical calcipotriene (Dovonex), topical tazarotene (Tazorac) and anthralin)
-Small doses of sunlight
What is Calcipotriene (Dovonex)?
A synthetic version of vitamin D3 with the same effects of corticosteroids (takes 8-12 weeks to appreciate the effects)
What is tazarotene?
A topical retinoid gel or cream indicated not only for psoriasis but acne and fine skin wrinkles (vitamin A derivative)
What can coal tar be combined with?
Ultraviolet B therapy
What kind of lesions does anthralin treat?
Chronic psoratic lesions
Should anthralin be used in acute or active eruptions?
What are the costs and benefits of topical retinoids?
These do not work as quickly as glucocorticoids but have fewer side effects; they should also not be used in skin folds
What is the Goeckerman" treatment?
Combines application of coal tar ointment and UVB phototherapy
What is PUVA?
A phototoxin that increases sensitivity to UV rays
What is a good method for treating small lesions?
Intralesional therapy (very effective)
What are the systematic therapies for psoriatic arthitis?
-Methotrexate, cyclosporine (can combine with UBA and UVB therapies)
What is lichen planus?
-An inflammatory pruritic disease of the skin and mucous membranes
-Idiopathic but has been associated with some liver disease
What does lichen planus look like?
-Purplish hexagonal lesion
-Predilection for the flexor surfaces and the trunk
-Bilateral and symmetrical
-Koebner's isomorphic phenomenon occurs regularly with lichen planus
-Deep hyperpigmentation may remain after lesion heals
What mucosal surfaces may be beneficial to examine in lichen planus?
Where do lichen planus lesions occur in the foot?
On the sides
What is the characteristic lesion of lichen planus?
•Small flat polygonal papules on the flexer surface
•These are violaceous in color (they may actually vary from red to purple, but most commonly a lavender hue) resting between and defined by, the natural lines of the skin
What are the elementary lesions of lichen planus like?
•Angular papule about the size of a pinhead
•May possess a central depression or umbilication at the site of a pore
•Possesses grayish puncta or streaks, Wickham's striae, which form a network over the surface of the papule
What are the oral muscoa lesions like in lichen planus?
•Generally located on the buccal mucosa
•Silvery-white pinhead sized papules
•Aggregations may appear in lace-like patterns
What are the nail changes associated with lichen planus?
•Pterygium formation is distinctive of lichen planus-skin migrates over the nail plate. This may lead to obliteration of the entire nail and is generally a permanent change
•Longitudinal grooving, ridging and splitting
•A peculiar midline fissure may occur
What is the treatment for lichen planus?
-Oral prednisone (extreme cases only)
-Dapsone and metronidazole (oral mucosa ulceration)
-Tranquilizers and anti-histamines (anti-pruritic)
What is pityriasis rosea?
•This is a mild inflammatory, moderately pruritic exanthem
•Typically have an acute onset lesions spread rapidly and then spontaneously disappear in three to eight weeks
-Etiology unknown but viral origin is suspected (Herp 6 or 7)
When is pityriasis rosea most common?
Autumn and spring, within families
How is pityriasis rosea distributed in the body?
On the trunk in a dermatome
What is the characteristic lesion of pityriasis rosea?
-Round or oval salmon-colored papular and macular lesions which arrange in a Christmas tree pattern on the trunk
-Can have a larger mother patch and spread to smaller patches
-Palms and soles are rarely affected
What is the treatment for pityriasis rosea?
-Geared towards symptom relief
-Water only baths
-Rarely a course of corticosteroids
What is Papular Purpuric Gloves and Socks Syndrome?
-An acute acral exanthem associated with parovirus B19 and CMV (also HHS-6)
When does Papular Purpuric Gloves and Socks Syndrome occur in the year?
Spring and Summer months
What is the clinical appearance of Papular Purpuric Gloves and Socks Syndrome?
•A symmetrical, sharply demarcated, purpuric or tender edema and erythema of he hands and feet
•Lesions are sharply marginated at the wrists and ankles
•It will progress gradually to purpuric papules and petchiae - taking on the appearance of a bruise
What is the treatment for Papular Purpuric Gloves and Socks Syndrome?
None, usually resolves in 1-2 weeks
What is Pityriasis Rubra Pilaris?
-Chronic skin disease affecting only the scalp first and the spreading to the extremities (phalanges)
-Only subjective symptoms may be mild pruritis
-Exaggerated gooseflesh appearance
What are the five types of Pityriasis Rubra Pilaris?
1) Type I - classic adult type - most common - 50% of all cases (51-55 year olds)
2) Type II - adult onset - atypical - 5% of all cases (long duration)
3) Type III - juvenile onset, classical - 10% of all cases (remission within a year)
4) Type IV - juvenile onset, circumscribed - 25% of all cases (associated sharply demaracated erythema and follicular keratosis, frequently located on the knees and elbows)
5) Type V - juvenile onset - atypical 5% of all cases (first 5 years)
6) Type VI has been described and is associated with HIV
What is the characteristic lesion of Pityriasis Rubra Pilaris?
•Small follicular papules - most important diagnostic feature
•Reddish brown, pinhead sized lesion topped by a central horny plug within which there is a hair
•It then evolves to orangey-red or salmon-colored (yellowish-pink) scaly plaques with well defined borders
•With chronic disease, the skin becomes dull red, glazed, atrophic, sensitive to very slight changes in temperature
What is a keratidermic sandal?
On the palms and soles, Pityriasis Rubra Pilaris lesions may coalesce to form a confluent hyperkeratotic erythroderma. This hyperkeratosis of the palms and soles has a tendency to fissure.
What are the nail changes seen with Pityriasis Rubra Pilaris?
•Dull, rough, thickened, brittle and striated
•There may be a distal yellow-brown discoloration
•Rarely - if ever - pitted (in contrast to psoriatic nails)
What is the treatment for Pityriasis Rubra Pilaris?
What is Kyrle's Disease (hyperkeratosis follicularis)?
•Characterized by the formation of large papules with central keratin plugs or cones that may develop in a widespread distribution pattern
•The cone projects into the dermis and is comprised or necrotic cellular debris and degenerated connective tissue
What is Kyrle's Disease (hyperkeratosis follicularis) associated with?
-Most commonly associated with chronic renal failure and dialysis and may be associated with an elevated phosphorus level
-It may be associated with diabetes mellitus, alcoholic cirrhosis, congestive heart failure, or may occur alone
What is the histological presentation of Kyrle's Disease (hyperkeratosis follicularis)?
-Keratin plug with necrotic debris
-Thin stratum malphigii
What is the clinical presentation of Kyrle's Disease (hyperkeratosis follicularis)?
•The primary lesion is a small papule with a central silvery scale which may grow to as large as 1.5 cm in diameter
•Lesions may coalesce to from circinate plaques
•Lesions are most common on the legs and forearms - especially on extensor surfaces
•They are often surrounded by a zone of erythema
What is the treatment for Kyrle's Disease (hyperkeratosis follicularis)?
-High doses of Vitamin A
-Vitamin E and Retin-A may be helpful
What is Darier's Disease (Keratosis Follicularis)?
•Characterized by hyperkeratotic papules in seborrheic regions and various nail abnormalities
•It is a chronic disease process
Generally inherited (desmosomes affected-SERCA mutation)
What is the clinical presentation of Darier's Disease (Keratosis Follicularis)?
•Lesions on the hands are most common but this may also involve the feet
•Small pits on the palms and soles are very characteristic - punctate keratoses
•Lesions may first appear as skin-colored papules which develop into persistent yellowish brown, greasy papules
•Symptoms include pruritis, but the appearance of the lesions is the major "morbidity" in the disease
What are the nail changes associated with Darier's Disease (Keratosis Follicularis)?
•There are white and red longitudinal bands and longitudinal nail ridges
•A V-shaped nick at the free margin of the nail is the most pathognomonic nail finding
What is the treatment for Darier's Disease (Keratosis Follicularis)?
What are the skin manifestations of syphilis?
What are the lesions associated with syphilis?
•Macular lesions are less than one centimeter in diameter
•Characterized by a light pink color which becomes brownish red
•The tint of these lesions is dependent upon the amount of pigmentation in the patient's skin
•Papular lesions are described as raw ham color or a coppery tint
What are macular eruptions of syphilis?
-"Ham-colored macules" on the soles of the foot
-Most common manifestation
-Occasionally a sequelae of a macular syphilid may be livedo reticularis
What are papular eruptions associated with syphilis?
-Ham or coppery in color or dusky yellow
-2 to 5 cm
-Covered with thick adherent scale (shiny appearance)
-Collarette of scale that overhang the border of the papule
-Ollendorf's sign is present - exquisite tenderness to direct touch or a papule with a blunt probe
What is the most common test used for syphilis?
What is the treatment of syphilis?
-Penecillin is DOC
-Jarisch-Herxheimer reaction may occur following the initial dose of penicillin
What is Reiter's Syndrome or Reactive Arthritis?
-A chronic form of arthritis characterized by a classic clinical triad or inflammation of the genital, urinary or gastrointestinal systems - urethritis, conjunctivitis and inflamed joints (arthritis)
-Believed to be precipitated by a bacterial infection in the genital, urinary or gastrointestinal tracts
What genotype is associated with Reiter's syndrome?
HLA-B27 in males
What is Keratoderma Blennorrhagicum?
-Genital and palmar lesions begin as multiple small yellowish vesicles which break and become confluent in Reiter's syndrome
-Start off waxy and papular, but become hyperkeratotic and scaly and become a psoratic plaque on the foot
What are the lesion of Reiter's syndrome like on the feet?
-A thick, dry, horny crusting frequently develops around the digits and spreads over the soles of the foot
What are the nail changes associated with Reiter's syndrome?
-Nails are thick and brittle
-Heavy keratotic tissue develops under the nail but isn't pitted
What are Palmoplantar Keratodermas?
•Keratin polypeptides in these disorders have been found to be different in proportion and type from those of normal skin
•Defects in the type I or type II keratin genes (chromosomes 12 and 17) disrupt the cytoskeleton and can cause loss of adhesion and cellular collapse
What are the hereditary Palmoplantar Keratodermas?
1) Unna-Thost - hereditary palmoplantar keratoderma
2) Mal de Meleda
3) Papilon-Lefevre syndrome
4) Mutilating Keratoderma of Vohwinkel
5) Keratosis Punctata Plamaris et Plantaris
What are the acquired Palmoplantar Keratodermas?
1) Keratoderma Climactericum
2) Arsenical Keratoses
A mutation in the glycine-rich cornified envelope protein loricrin has been discovered in what disease?
Vohwinkel's keratoderma when associated with ichthyosis
What is Unna-Thost Syndrome - Hereditary Palmoplantar Keratoderma (PPK)?
Autosomal dominant inheritance pattern with high penetrance characterized by thickening of the epidermal horny layer of the palms and soles with a tendency to spread on to the dorsal surfaces of the hands and wrists
Where is the underlying defect in Unna-Thost Syndrome?
Keratin gene cluster 12q13 (type II keratin gene)
What condition commonly occurs with Unna-Thost Syndrome?
What is the characteristic lesion of Unna-Thost Syndrome?
-Hyperkeratosis extends to the lateral borders and knuckles of the involved palms and soles
-No inflammation or erythema
-Well defined borders
What are the two clinical varieties of Unna-Thost Syndrome?
1) "waxy rough surface types"-fissuring
2) "sclerodermoid types"-no fissuring
What are the nail changes associated with Unna-Thost Syndrome?
Thickening, opacity, malformation
What is the podiatric treatment of Unna-Thost Syndrome?
What is Howel-Evans Syndrome?
•Autosomal dominant inheritance pattern associated with the tylosis esophageal cancern gene which is localized to a small region on band 17q25
•Palmoplantar keratoderma associated with oral leukokeratosis and follicular hyperkeratosis
•Hyperkeratotic lesions may appear yellow and waxy on weight-bearing surfaces of the feet
What is Mal de Meleda?
-Stocking-glove distribution of hyperkeratosis
-Enlarged sweat glands and thick stratum corneum
-Associated with hyperhidrosis and occasionally bromhidrosis
-Occasionally presents with nail dystrophy
How does Mal de Meleda progress?
-Palmar and plantar erythema at birth, which diffuses but keratoderma stays (eryothematous border remains)
What is the treatment for Mal de Meleda?
What is Papillon-Lefevre Syndrome?
-Stocking-glove symmetrical distribution of hyperkeratosis (similar to mal de meleda)
-Autosomal recessive inheritance pattern
-Loss of teeth
What is the characteristic lesion of Papillon-Lefevre Syndrome?
•Diffuse hyperkeratosis on the palms and soles and occasionally extending onto the dorsums of the hands and feet
•Keratosis, like mal de meleda, possesses erythematous borders
•Hyperkeratosis may be associated with severe scaling and fissuring
•Gingival dysplasia and alveolar bone alterations occur in the mouth and jaw
What are the nails like in Papillon-Lefevre Syndrome?
Transverse grooves of the nail plate
What is the podiatric treatment of Papillon-Lefevre Syndrome?
-Shoe gear modification
What is Mutiliating keratoderma of Vohwinkel - Keratoderma Hereditarium Mutilans?
-Autosomal dominant frameshift of the loricrin gene (endcoding connexin 26 abnormality from chromosome region 13fq11-q12 abnormality)
Connexin 26 mutations are attributed to?
Non-ysyndromic sensorineural deafness
Connexin 31 mutations are attributed to?
What are the characteristic lesions of Mutiliating keratoderma of Vohwinkel - Keratoderma Hereditarium Mutilans?
•Honeycombed hyperkeratotic variant of diffuse palmoplantar hyperkeratosis
•Associated with starfish-like keratoses on the backs of the hands and feet
What is Hidrotic ectodermal dysplasia - also known as Clouston's syndrome?
•It is a rare autosomal dominant disorder characterized by palmoplantar hyperkeratosis, generalized alopecia and nail defects
•This has been mapped to the same region as Vohwinkel's syndrome
What is Keratosis Punctata Palmaris et Plantaris?
•Autosomal dominant inheritance pattern
•Discrete, firm, slightly elevated hyperkeratotic papules on the palms and soles
•Lesions are quite numerous
•Keratotic plugs range from 2 to ten millimeters in diameter
What is Keratoderma Climactericum - Hauxthausen's Disease?
•Initially appear as reddish-brown circumscribed papules
•Over time, these papules develop into thickened plaques
•Plantar eruptions tend to spare the longitudinal arch and concentrate more on weight bearing areas of increased pressure
•Skin creases become exaggerated and may fissure
What is the treatment for Keratoderma Climactericum - Hauxthausen's Disease?
-Topical estrogen or oral estrogen
What is Arsenical Keratosis?
-Cutaneous manifestation of arsenic intoxication (targets sulfhydryl groups)
-Arsenic alters the keratinocyte differentiation process
What are the characteristic lesions in Arsenical Keratosis?
-They have been described as "honeycomb-like elevations, usually 2 to 5 millimeters in diameter"
-These eruptions generally extend to encompass the palms and soles, sparing the longitudinal arch of the foot
-Patients can be bronzy in pigment and have a raindrop appearance depigmentation and hyperpigmentation
What are the associated systematic signs with Arsenical Keratosis?
What are Porokeratotic Disorders?
-Characterized by a localized point of faulty keratinization
-Thickened column of keratin contains a parakeratotic nuclei extending from a notch in the malpighian layers and is referred to as a coronoid lamella
What is Porokeratosis of Mibilli?
•Chronic progressive disease with autosomal dominant transmission
•Lesions have the potential to transform into carcinoma
What is the clinical appearance of Porokeratosis of Mibilli?
•It begins as a small crater-like keratotic papule and spreads peripherally
•Lesions may coalesce developing into a circinate or serpiginous well-defined plaque
•In the fully developed lesion, a keratotic wall or collar develops
•The collar is characteristically brown or gray in color
•The skin in the central portion of the plaque becomes dry, smooth and atrophic
What is the nail involvement in Porokeratosis of Mibilli?
Thickening and dystrophy may occur if the lesions involve the nail matrix
What is the treatment for Porokeratosis of Mibilli?
-Lesions of porokeratosis of Mibelli should excised or destroyed
What is Porokeratosis Plantaris Disseminata?
•Multiple, painful focal hyperkeratotic lesions
•Generally confined to the weight bearing portions of the sole
What are the characteristic lesions of Porokeratosis Plantaris Disseminata?
•Sharply demarcated, rubbery, wide-based papule
•It is a central epidermal depression filled by a compact hypekeratotic plug
It should not bleed with debridement
What is the treatment of Porokeratosis Plantaris Disseminata?
-Injection therapy with a 4% absolute alcohol preparation underneath the lesions may be effective
What is Porokeratosis Discreta?
These is considered to be a forme fruste of porokeratosis disseminate by some and a complete misnomer by others
What is an Eccrine Poroma?
•A benign tumor of the intraepidermal portion of the eccrine sweat duct
•It is a soft to firm, fleshy to erythematous appearing nodule with a sessile or pedunculated base
•Occurs most commonly as a solitary, slowly growing lesion and is most common on the sides and soles of the foot
How is the eccrine poroma distinguished histologically?
•A solid mass of uniform, very small basophilic cuboidal epithelial cells
•It arises from the lower epidermis and extends down into the dermis
•There is a distinct separation between normal epidermal cells and the poroma tissue
What is the treatment for errice poroma?
Complete surgical excision
What are the clinical differential diagnoses for eccrine poromas?
•hemangiomas, pyogenic granulomas
•amelanotic malignant melanoma
•Kaposi's hemorrhagic sarcoma
•basal cell carcinoma
What is Pyogenic Granuloma?
•A small, sessile or pedunculated, raspberry-like vegetation from an aggregate of capillaries arranged in a nodule
•Dull red in color and is very "friable" meaning that they bleed easily with the slightest trauma
•It occurs most commonly on exposed surfaces of the body
What is the treatment of Pyogenic Granuloma?
•"Shelling out" the lesions with a curette followed by carbon dioxide laser ablation or fulgaration of the base is generally effective
•Smaller lesions may respond to cauterization following removal with silver nitrate sticks
What is the differential diagnosis of Pyogenic Granuloma?
•Kaposi's sarcoma, melanoma, melanotic whitlow
•Senile angioma or metastatic carcinoma
What is Seborrheic Dermatitis/Keratosis?
•A common, superficial chronic inflammatory disease of the skin
•Parkinson's disease may exhibit a severe seborrheic dermatitis of the scalp and face, also very common in obese DM patients
•The scaling is profuse and there is very little associated erythema
What are the histological characteristics of Seborrheic Dermatitis/Keratosis?
-Neutrophils in the stratum corneum and stratum granulosum
-Dermis has cell inflammatory infiltrate
What is the characteristic lesion of Seborrheic Dermatitis/Keratosis?
•Loose dry, moist or greasy scales - they may bear a close resemblance to psoriasis
•There may be pinkish or yellowish patches of various shapes and sizes
•Lesions may be surrounded by erythema, scaling, oozing and pruritus which may in the early acute stages be quite intense
What is the treatment for Seborrheic Dermatitis/Keratosis?
Selenium sulfide (Selsun), tar, zinc pyrithionate and resorcin (shampoos) and corticosteroids
Where does Actinic or Solar Keratosis occur?
Sun exposed areas of the body
What is the characteristic lesion of Actinic or Solar Keratosis?
•Lesions are commonly 1 to 2 cm in diameter
•Generally multiple, discrete, flat or elevated, verrucous or keratotic, red, pigmented or skin colored patches or scales
What is the treatment for Actinic or Solar Keratosis?
•Liquid nitrogen is very effective and practical for lesions occurring on the back and face
•In the presence of broad, extensive lesions - 5-fluorouracil topically is effective
•Carbon dioxide laser ablation is quite effective
•Oral etritinate has also been proven to be efficacious
•Prophylaxis against future lesions is imperative with the use of total UV blocking sunscreens
What is a Cutaneous Horn?
•Skin colored, horny excrescences (benign usually)
•Average size between 2 to 60 mm long and may actually subdivide into antler-like projections
•Usually possess slightly reddened and thicker base
What is the treatment for a cutaneous horn?
What is a Keratoacanthomas?
•Fairly common, benign, epithelial tumors
•Possibly arise from a viral origin, occurs on sun exposed areas of the body
What is the clinical appearance of Keratoacanthomas?
•The initial lesion is a smooth, come-shaped red papule and may resemble molluscum contagiosum or verruca vulgaris
•It possesses a central keratin-filled plug which may become crusted
•Telangiectasias may course through the lesion
•The border of the lesion is sharply demarcated from surrounding tissue
•A variant, giant keratoacanthoma, may continue to grow in size and develop a central, necrotic crater
•Clinically, it possess a cup-like invagination of the epidermis
What is the treatment for Keratoacanthomas?
-Injection therapy of 5-fluorouracil or triamcinolone may be successful
What does allergy mean?
Changed reactivity of the host when meeting an "agent" on a second or subsequent occasion
What layer of skin is involved in an allergy?
Superficial skin (so no scaring)
What are the types of allergic immune reactions?
What is a type 1 allergy reaction?
-Immediate or anaphylactoid - IgE mediated urticaria
-Directly against environmental agents
-Mast cell responses
-Eg. include asthma, eczema, hay fever, urticaria, rhinitis and food allergy
What is a type 2 allergy reaction?
-Cytotoxic - immune hemolytic anemia
-Antibody dependent reaction
-Macrophages, neutrophils, eosinophils, and killer cells
-Damage to the basement membrane
What is a type 3 allergy reaction?
-Immune complex - leukocytoclastic vasculitis
-C3a and C5a produced: "serum sickness"
-Platelets, basophils, and mast cells increase vascular permiability
-Can be caused by autoimmune disorders and persistent infections
What is a type 4 allergy reaction?
-Delayed hypersensitivity - allergic contact dermatitis
-Antigens are trapped and macrophages can't be cleared
-T cells give inflammatory response
-Eg. graft rejection and contact dermatitis
What is urticaria?
-Acute urticaria is generally a type I hypersensitivity reaction mediated by mast cell activation - fixed IgE
-Chronic urticaria occurs when symptoms been continuously or intermittently present for at least six weeks
What is the important biochemical mediator in urticaria?
What is the treatment for urticaria?
-Acutely it resolves itself, oral antihistamines, epi if major event
-Treatment of chronic is challenging
What is the acute stage of eczema?
-Begins with the formation of vesicles, blisters or bullae
-Severe pruritis is the most common and often most intense symptom
What is the subacute stage of eczema?
-Stage generally involves redness, scaling and fissuring
-The skin may take on a parched or burned appearance
-The patient may complain of burning discomfort at this stage and mild to moderate pruritis
What is the chronic stage of eczema?
-Involves lichenification - skin line become accentuated and excoriations are often present
-The lesion generally continues to be moderately pruritic
What is the histological hallmark of ecsema?
-Spongiosos eruptions with inflammatory infiltrate of the dermis
-Also has honey-colored crust (keratin)
What is Dyshidrotic Eczema?
-Blister escema: an intraepidermal vesicular eruption localized to the palms, soles and interdigital spaces
-Symptoms characteristically consist of pruritis and burning
What is the characteristic lesion of Dyshidrotic Eczema?
-Small deep seeded intraepidermal vesicles resembling "sago grains" filled with a clear or straw colored fluid
What is the treatment for Dyshidrotic Eczema?
-Topical high potency corticosteroids
-Soaking in permanganate solution
What is Lamellar dyshidrosis - Keratolysis Exfoliativa?
•Superficial exfoliative dermatosis affecting the palms and soles
•Characterized by the absence of any inflammatory changes
What is the characeristic lesion of Lamellar dyshidrosis - Keratolysis Exfoliativa?
•Initially, it will appear as tiny pinhead-sized white spots
•These spots tend to spread peripherally
•As the spots spread, the central horny layer ruptures and peels off
•The skin may take on a flaky appearance from desquamation of the superficial stratum corneum
What is the treatment for Lamellar dyshidrosis - Keratolysis Exfoliativa?
What is allergic contact dermatitis?
•A type IV delayed hypersensitivity reaction
•Does not occur on the first exposure to the allergen (i.e. requires sensitization)
What is the etiology of allergic contact dermatitis?
Mediated by the Langerhans cells, T lymphocytes and T-cell lymphokines
What is the clinical recognition for allergic contact dermatitis?
-Acute eruption about 48 hours after exposure
-Lesions are edematous red papules developing into vesicles and bullae when the reaction is severe enough
-Chronic exposure results in minimal primary lesions with secondary changes such as lichenification, pigment changes, hyperkeratosis, excoriation and fissuring can occur and predominate the clinical presentation
How do you diagnose allergic contact dermatitis?
-Locale, pattern and morphology of the lesion
-Presence of spongiosis
What is the treatment for allergic contact dermatitis?
-Need to ID the offending agent to eliminate symptoms
-Corticosteroids can work for acute attacks
-Topical steroids and oral antihistamines are good for chronic issues
-Tacrolimus and pimecrolimus work for peds
What is non-allergic or irritant dermatitis?
The result of direct contact with a noxious agent (housecleaning products)
What is the clinical presentation of irritant dermatitis?
-The patient will present with itching papules or vesicles
-Presentation may vary from slight hyperkeratosis and small fissures to extensive redness, swelling and oozing
-Inflammation agents start in epidermis and extend into the dermis but leave no scarring
What is photocontact dermatitis?
-Reaction to substance in the skin and UB light (longwave UV - 320 - 400 ng UVA)
What is the clinical presentation for photocontact dermatitis?
•The most common presentation is the morbilliform or exanthematous eruption
•This is typically widespread, pruritic and symmetrical
•Eruption is generally comprised of multiple pink macules and papules which may become confluent
What are the less common presentations of photocontact dermatitis?
•Acneiform eruptions - these tend to occur on the torso and chest, drug induced folliculitis
•Lichenoid drug eruptions-imitate lichen planus
•Photosensitivity reactions- generally appear with diffuse erythema with later desquamation
•Vasculitis and vesiculobullous eruptions - quite rare, palpable itchy papules and blistering lesions
What is asteototic dermatitis?
•This is also known as xerotic eczema, winter itch and eczema craquele
•It is characterized by dehydration of the skin which results in dehydration of the stratum corneum
What are the characteristic lesions of asteototic dermatitis?
•Skin will present with redness, very fine superficial cracking and fine flakes, Very itchy
•Xerotic eczema will show a condensed or "packed" appearance to the outer keratin layer with minimal spongiosis and inflammatory infiltrate
What is nummular eczema?
•This is also referred to as discoid eczema due to the clinical appearance of the coin-shaped erythematous lesions
•Nummular eczema will show spongiosis and a mixed cell inflammatory infiltrate as well as psoriasiform epidermal hyperplasia
•It often occurs concomitantly with venous stasis dermatitis
•It generally presents with dry skin and is more common in the winter
What is Lichen simplex chronicus?
•Also known as neurodermatitis circumscripta
•Have a predilection for the extremities - especially the wrists and ankles (particularly the ankle flexure)
•Initially, lesions may appear erythematous with coalescing vesicles
•Linear excoriations may also be present
•With time, the lesion becomes thickly lichenified, scaly and elevated with accentuated skin lines
What is Prurigo nodularis?
•This is considered a variant of lichen simplex chronicus
•It is characterized by discrete or multiple hyperkeratotic nodules
•It occurs most frequently on the lower extremities on the extensor surfaces of the feet
What is the clinical presentation of prurigo nodularis?
•The pruritis is the most prominent feature, lesions occur as a result of the chronic picking in an isolated area
•The nodules are erythematous or brownish, indurated and may be dome-shaped
•The center of these lesions may be smooth, crusted or when the disease process becomes chronic, warty in appearance
•The lesions are generally "pea-size" but may be as large as 2 cm in diameter
What is Erythema Nodosum?
•An acute reactive process occurring as erythematous, tender subcutaneous nodules on the lower extremities - particularly the shins
•It is an inflammatory process resulting in delayed hypersensitivity reaction with involvement of the larger cutaneous blood vessels
•Histologically, it is a septal panniculitis.
What is the clinical presentation of Erythema Nodosum?
•The onset of an attack is typically heralded by constitutional symptoms such as fever, malaise, myalgia and arthralgia - generally fairly mild
•Lesions begin as red, tender, smooth nodules that are usually symmetrically distributed on the anterior shins, size may vary from 2 to 6 centimeters
•During the first week, lesions are firm, indurated and tender
•As the lesions evolve, they develop a fluctuant consistency
What is Erythema Multiforme?
-These xanthem have been viewed as a hypersensitivity syndrome - therefore, suggesting the presence of an underlying antigenic stimulus
-Manifests not only in the skin but in the mucous membranes
-"Multiforme" refers to the multiple and varied skin reactions associated with this hypersensitivity response ("multiformity" is the prominent feature of this disease)
What is the lesion like in Erythema Multiforme?
•There are many varieties of erythema multiforme and they are classified according to the more prominent feature composing the eruption
•The lesions may be macular, papular, nodose, vesicular or bullous; annular, circinate or iris-shaped
•Symptoms may include urticaria, pruritis and may be persistent
•Main sites of predilection in the lower extermities include the legs and dorsum of the feet
What are the maculopapular presentations like in Erythema Multiforme?
•Lesions are bright bluish red, well defined macules or edematous flat-topped papules
•Erythema iris, characterized by concentric rings, is found chiefly on the ankles
•Variegated tints of lesions may exist ranging from a particularly bluish and yellowish mixture with red
What are the etiologies of Erythema Multiforme?
1) Bacterial infections
2) Viral infections
3) Mycotic infection
4) Collagen vascular disesase
What are the characteristics of Erythema Multiforme Bullosum - Erythema Multiforme Minor?
•Bulla are frequently large on an erythematous base
•It most commonly occurs on the palms and soles
•Pruritis is generally absent
Can have respiratory symptoms and concommitant subungual hemorrhaging
What is Stevens-Johnson Syndrome - Erythema Multiforme Major?
-A mucocutaneous disorder heralded by the acute and abrupt onset of a fever of 39 to 40 degrees C, headache, malaise and a sore throat
-Abrupt onset and more severe than minor multipforme
-The more extensive nature of these lesions is associated with a relevant increase in tumor necrosis factor alpha (TNF-alpha)1 and intense expression of interferon gamme in the superficial dermis and epidermis of these lesions (Stevens Johnson and Lyell's)
-Usually after an infection of herpes simplex or Mycoplasma pneumoniae
What are the characteristic lesions of Stevens-Johnson Syndrome?
•Vesicles on the lips, tongue and buccal mucosa
•These lesions progress to pseudomembranous exudation and ulceration
•Presence of an erythematous, pruritic cutaneous eruption
What is Toxic Epidermal Necrolysis - "Lyell's Syndrome"?
-It is a vesico-bullous condition in the most extreme presentation
-It is so severe that it has the appearance of a widespread scalding burn
-Goes through the full thickness of the epidermis (TEN lesions)
-TNF-alpha is in the epidermis
What is the clinical presentation of Toxic Epidermal Necrolysis - "Lyell's Syndrome"?
•Characterized by widespread blistering of the skin
•It is so severe that it has the appearance of a widespread scalding burn
•20-50% of the body can be involved
What are Acrochordons?
-Associated with seborrheic keratosis
What is the clinical presentation of Acrochordons?
•Small, flesh to dark brown colored, sessile, pedunculated, papillomatouc lesions
•On the plantar surface of the foot, these lesions tend to become flattened
•Lesions are generally asymptomatic unless there is some type of external irritation
(can be clipped and cauterized)
What is a gual Fibroma - Kernan's Tumor?
•These lesions may become large enough to disrupt the entire nail bed
•These are associated with tuberous sclerosis 50% of the time
•Firm, smooth flesh-colored growth protruding from the nail folds
•Coloration may vary from yellow to pink and may be irritated by shoegear and bleed
What is an Acral Fibrokeratoma?
•Classically, it presents as a smooth, dome-shaped papule that is asymptomatic and is usually solitary
•It is characterized as a benign, acquired pinkish, hyperkeratotic, hornlike projection
•This projection usually emerges from a collarette of slightly elevated skin - which an important differentiating factor
•It usually occurs on the digits but may occur on the palms and soles
What is a dermatofibroma?
-Common nodular lesion common on the LE, above the elbow, and on the trunk
-Masses of close "whorls" of fibrous tissue
What is the clinical presentation of a dermatofibroma?
•It is a single, round or ovoid papule or nodule about 1 cm in diameter
•It is reddish brown - sometimes with a yellowish hue - and occasionally has a slightly scaly or velvety appearing surface
•Diagnosis may be aided by the "dimple sign" - that is upon squeezing the lesion from side to side, it may actually involute
What is a Plantar Fibromatosis - Ledderhose's Syndrome?
•Plantar fibromatosis occurs as a slowly enlarging nodules on the sole - most common on the medial band of the plantar fascia
•Firm, indurated nodules generally involving the medial band of the plantar aponeurosis
•The skin is freely moveable over the lesion
•Usually non-tender with palpation and do not luminesce
What are Synovial or Myxoid Cysts - Digital Mucin Cysts?
•These result from focal accumulations of mucin in the dermis of the dorsal aspect of the distal phalangeal or proximal nail folds
•Usually present as singular lesions
-Not true cysts, but pseudocysts
-Can be accompanied by OA
•They are usually noninflamed, solitary, skin-colored or bluish nodules ranging in size from 5-8 mm
•Opalescent, shiny, dome-shaped, smooth surfaced lesions which luminesce
•With distal interphalangeal joint lesions, the nail plate may demonstrate longitudinal grooving or ridging
What is a ganglionic cyst?
•They are herniations of the joint linings and often associated with exostoses
•These may be the most common of all lesions affecting the joint and joint structures
•They occur most frequently over the wrists and ankle, heel or dorsum of the foot
What are the lesions in a ganglionic cyst?
•Lesions may or may not be symptomatic depending upon the surrounding tissues that they impinge upon
•Lesions are fluctuant upon palpation and luminesce
What is an Epidermoid Cyst aka Epidermal Inclusion Cyst?
•Result from the implantation of epidermal elements within the dermal tissues
•Sonogram will reveal a hypoechoic mass
•The cyst is generally lined with stratified squamous epithelium containing
•The lesion is filled keratinous material often with a lamellar arrangement
•Older cysts may become calcified or may actually rupture if the body mounts a foreign body
How is Tumoral Calcinosis characterized?
-Periarticular deposition of calcium phosphate primarily in the upper and lower extremities
-An extraskeletal soft tissue mass
-The mass itself is firms, multilobular and nonencapsulated with a yello-white pasty exudates
What is a leiomyoma?
•This is a benign tumor arising from smooth muscle
•Cutaneous lesions arise most commonly from the arrector pili muscles
•Symptoms are exacerbated by cold weather - "goose bump" conditions
•As cutaneous leiomyomas lesions develop, they become quite painful and are fixed within the skin
What is a Leiomyosarcoma?
•This is the malignant variant of a smooth muscle tumor
•They have a tendency to metastasize and can be quite deadly
What are glomus tumors?
-Benign neuroarterial lesions composed of vascular channels surrounded by nerve fibers
-They arise from the arteriovenous shunts and richly innervated tissue of the periungual and subungual digital pulp - the glomus bodies
What is the clinical presentation of a glomus tumor?
•Lesions appear slightly dusky blue or with focal erythema and are often visible through the nail plate
•Patients will describe the pain as shooting or pulsating
•It is generally constantly tender and exquisitely painful with paroxysmal exacerbation
•Classic triad: 1) Pinpoint tenderness, 2) Paroxysmal pain, 3) Cold hypersensitivity
What are the tests for glomus tumors?
•Love's test - apply pressure with a small probe (such as a paperclip) to localize the maximal point of tenderness
•Hildreth's test - apply a tourniquet to the base of the digit and repeat Love's test. If symptoms abate, it suggests glomus tumor.
•Cold Sensitivity Test - exposure to cold will reproduce symptoms
What are Piezogenic Papules?
•These are herniations or protrusions of the plantar subcutaneous tissue through the connective tissue striae of the plantar fat pad
•They typically occur on the medial and lateral aspects of the heel pad
•These lesions occur in patients who are extremely obese, excessively pronate or stand for long periods of time
•Most papules are asymptomatic, however, some will occasionally strangulate resulting in anoxic pain
What is xanthoma?
•They are flat, yellow plaques, papules or nodule
•These occur secondary to the deosition of lipids in the skin as a result of hyperlipidemia, primary hyperlipoproteinemias, familial hypercholesterolemia and familial hyperbetalipoproteinemia
What are the characteristics of tuberous xanthomas?
•May develop as slow growing yellow papules or nodules, tend to coalesce
•Affect the knees, elbows and extensor surfaces of the extremities
•They may also involve the knuckles and toe joints
What are tendinous xanthomas?
-Smooth and attached to tendons, ligaments and deep fascia
-These occur frequently on the tendo achilles
What is a lipoma?
•Subcutaneous tumors composes of fat tissue
What is the clinical presentation of a lipoma?
•Lesions are generally asymptomatic unless impinging on surrounding vascular or neural elements
•Lesions are fluctuant with palpation and luminesce
•They are loosely encapsulated, lobulated lesions
•Skin overlying a lipoma may exhibit dimpling when pulled (resembling cellulite)
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