Hard, rough surface formed by dried sebum, exudate, blood, or necrotic skin
What is a scale?
Thin flakes of horny epithelium with a dry appearance
What is a pustule?
Vesicle or bulla containing purulent material
What is an erosion?
Loss of epidermis; heals without a scar
What is an ulcer?
Defect that extends in to the dermis or deeper; heals with a scar
What is a fissure?
What is annular? Gyrate? Nummular? Targetoid? Serpiginous? Filiform? Pedunculated? Umbilicated/molloscum?
Annular - ring Gyrate - circular Nummular - patches Targetoid - like a bull's eye (Lyme's) Serpigenous - snake like Filiform - finger like Pedunculated - Ex: skin tag Umbilicated/Molloscum - papule with indentation in the middle
What is Darier sign?
Rubbing a lesion causes urticarial flare
What is Auspitz sign?
Pinpoint bleeding after scale is removed. Seen with Psoriasis.
What is Nikolsky sign?
Top layers of the skin slip away from the lower layers when slightly rubbed.
What is Koebner phenomenon?
Minor trauma leads to new lesions at site of trauma. Seen in Psoriasis and LP.
How is eczema and dermatitis the same? How are they different?
They are both used to describe polymorphic inflammatory reaction pattern involving the epidermis and dermis. However, eczema is usually caused by an endogenous disorder whereas dermatitis is usually caused by something exogenous
What is eczema/dermatitis characterized by?
Pruritis Erythema May also have: +/- vesciulation Xerosis (dry skin) Lichenification Hyperkeratoses Fissures
What are two types of contact dermatitis?
Irritant - caused by a chemical (ex: detergents) Allergic - caused by an allergen (ex: poison ivy)
What is diaper dermatitis?
AKA Diaper rash. Usually due to prolonged contact with urine, feces, or detergents from washable diapers.
What is diaper rash often associated with and what is the characteristic finding?
Candida infection which is characterized by satellite lesions
How do you treat diaper dermatitis?
Topical Nystatin Fluconazole Keep area clean and dry
What are characteristics of irritant contact dermatitis?
Affected area is sharply marginated and confined to area of contact. Signs: Erythema, vesicle, erosion, crust, scale Could occur within a few hours or over months
What are characteristics of allergic contact dermatitis?
Due to type IV cell mediated or delayed hypersensitivity reaction Must be sensitized to offending agent Can spread beyond contact area or generalize Signs: Erythema, papules, vesicle, erosions, crusts, scales Occurs within 12-72 hours LINEAR FORMATIONS
What are some common chemicals that cause irritant CD?
Soaps, cleaners, solvents, detergents
What are some common allergens that cause allergic CD?
Antibiotics Metal salts Dyes Plants Oils Nickel Latex
How do you diagnose contact dermatitis?
Usually clinical diagnosis Patch test (for allergic CD only)
How do you treat contact dermatitis?
Remove offending agent Wet dressings soaked with Burrow's solution (aluminum acetate in water) Topical corticosteroids (Class I or II) Do not pop blisters If severe: systemic corticosteroids with a 2 week taper starting at 60mg Supportive care: mild soaps, oatmeal baths, antihistamines
What is seborrheic dermatitis?
Very common dermatitis during infancy, puberty, and young adults. Occurs where sebaceous glands are most active (body folds, face, scalp, genitalia). AKA "Cradle Cap" in infants. Dandruff in adults
What is the possible etiology of seborrheic dermatitis?
Malassezia furfur (overgrowth of fungal/yeast organism)
What are characteristics of Seborrheic Dermatitis?
Can be chronic, recurrent. Scattered yellowish or gray, scaly macules and papules with a greasy look. Can present differently on different parts of the body: Ears - sticky crusts Scalp - dandruff Trunk - yellow-brown patches Body folds- sharply marginated, erythematous eruption
How do you treat Cradle cap Seborrheic Dermatitis in infants?
Warm olive oil compresses and baby shampoo 2% Ketoconazole shampoo Hydrocortisone cream Selsun Blue (selenium sulfide)
How do you treat Seborrheic dermatitis on other areas of the body (face, trunk)?
An eczematous disorder that presents with a HERALD PATCH which precedes as wide spread symmetrical papular eruption.
What is the cause of Pityriasis Rosea? Who does it most commonly affect and when is the highest incidence?
Thought to be human herpes virus 7. Mostly affects teenagers and adults. Highest incidence is in the fall and spring.
What is a herald patch?
An oval, slightly scaly plaque ~ 2 cm. Salmon colored with a fine collarette of scale.
What happens after about 2 weeks with Pityriasis Rosea?
Scaling papules and plaques form a CHRISTMAS TREE distribution on the trunk.
How do you treat Pityriasis Rosea?
Usually self-limited (6-12 weeks) Can do antihistamines, topical steroids, UVB light, lotions for symptomatic treatment.
What is Psoriasis?
A chronic, inflammatory, scaling condition of the skin. The earlier the onset, the more severe the disease. There is greatly enhanced epidermal cell turnover.
What is the most common variant of psoriasis? Which populations is it most common in?
Psoriasis vulgaris; Jewish and Mediterranean
Which form of psoriasis involves the entire skin surface?
What are clinical features of Psoriasis?
Raised pink to red papules and plaques with distinct margins and loosely adherent SILVERY SCALES. +Auspitz sign Koebner's phenomenon is seen Usually found on scalp and extensor surfaces of elbows and knees
What are clinical features of extensive Psoriasis?
Nails have pits and ridges and can be separated from nail bed (onycholysis) Oil spots on nails
How do you diagnose Psoriasis?
How do you treat Psoriasis?
Mild - topical steroids and topical Vitamin D (calcipotriene) Oral steroids for systemic disease Topical coal tar or salicylic acid and occlusive dressings for removing scales Moderate - tazarotene gel (topical retinoid) Severe - UVB, PUVA, methotrexate
Erythema multiforme minor (EM) Erythema multiforme major (Includes SJS, TEN)
What is Erythema Multiforme (EM)?
An acute inflammatory disease which is usually induced by drug hypersensitivity or preceding infection.
Frequent recurrences Lesions begin as macules and become papular. Then vesicles and bullae form in the center of he papules. Targetoid IRIS lesions are characteristic. Typically occurs on extremities MUCOSAL LESIONS that are painful and erode.
How do you treat EM?
Self-limiting disease Supportive care: Antihistamines, topical steroids, prednisone Control Herpes outbreaks with Acyclovir
What are differentiating factors between EM and SJS or TEN?
EM: Occurs in young males Frequent recurrences Less fever Milder mucosal lesions No association with a collagen vascular disease, HIV, or cancer
What is Stevens-Johnson Syndrome (SJS)?
A vesiculobullous disease of the skin, mouth, eyes, and genitalia. Ulcerative stomatitis leads to hemorrhagic crusting. <10% skin loss
Keep affected area clean Retinoids Azelaic Acid Salicylic Acid
Why is Benzoyl Peroxide added to topical antibiotics for treatment of acne? What is the downside of BP?
BP helps prevent antibiotic resistance in combo with orals. Downside: Will bleach clothing
How do you treat moderate to severe acne?
Oral antibiotics with topicals Tetracyclines are abx of choice Oral isotretinoin (Accutane)
What is a typical regimen for Acne?
Oral antibiotic - Doxycycline with Topical antibiotic/BP combo in AM (Benzaclin) with Topical retinoid at night - (Differin)
What is the antibiotic class of choice for the treatment of severe acne?
What is Acne Rosacea?
Chronic acneiform disorder and disease of pilosebaceous units associated with increased activity of capillaries which leads to flushing
What characterizes Rosacea?
Insidious onset of scattered, small papulopustules and sometimes nodules, in which comedones are absent and the face appears red or flushed
What are the three stages of Rosacea?
Early - Persistent erythema and telangectasias Middle - Persistent erythema, telangectasias, papules, tiny pustules Late - Deep erythema, papules and pustules
Who does Rosacea most often affect?
What are triggers for Rosacea outbreaks?
Heat, alcohol, sun, hot spicy foods, coffee/tea (bc of heat not caffeine)
What are clinical features of Rosacea?
Scattered, small papulopustules and sometimes nodules No comedones! Face appears red/flushed in a symmetric distribution Later telangiectasia, hyperplasia (enlargement of nose, ears, eyelids, forehead, chin), and lymphedema occurs
How do you treat Rosacea?
Avoid triggers Topical metronidazole Systemic abx of topical fails Oral isotretinoin for severe cases
What does the suffix -phyma mean?
How do you treat rhinophyma and telangectasias associated with Rosacea?
Surgery or laser treatment
What is the most common cause of folliculitis?
What is the cause of folliculitis seen in hot tub users?
What pathogens cause the most pediatric infections?
Exanthems Varicella Molluscum Verrucae
What are the 6 childhood exanthems (rash-causing diseases)?
AKA Rubeola 3 C's: Cough, Coryza (cold-like symptoms), Conjunctivitis 4 day fevers KOPLIK's SPOTS- oral lesions that appear before the rash Macular-papular rash in the hairline that spreads down over 3 days
How do you treat Measles?
Supportive care - Measles is self-limiting (lasts 7-10 days)
What is a rare complication of Measles?
Subacute sclerosing panencephalitis (SSP) - fatal encephalitis that occurs years after initial infection
What is Scarlet fever?
AKA "SCARLETINA". Most commonly affects children between 5 and 12 years of age. Caused by GAS which release erythrogenic exotoxin.
What are clinical features of Scarlet fever?
Classic symptoms: SANDPAPER rash in groin, axilla with DESQUAMATION (peeling) after 3-4 days. Strep symptoms: Pharyngitis, fever Bright red tongue with a "STRAWBERRY" appearance
How do you treat Scarlet fever?
PCN VK or Amoxicillin
What is German Measles?
AKA "RUBELLA" Symptoms last 2-3 days Half of patients with Rubella are asymptomatic
What are clinical features of German Measles?
Rash that starts on the face and spreads to the rest of the body (less intense than measles) Low grade fever Postauricular and occipital adenopathy Aching joints, especially among young women. FORCHEIMER spots (fleeting small, red spots on the soft palate) - can also be seen with measles and scarlet fever.
How do you diagnose Rubella?
Usually a clinical diagnosis Can do paired sera - get a blood sample now and then in a week. This is usually done in immunocompromised patients.
How do you treat Rubella?
What is Erythema Infectiousum?
AKA 5th disease Caused by Human Parvovirus B19
What are clinical features of Erythema Infectiosum?
Mild flu like illness Rash at 10-17 days (not contagious with rash) SLAPPED CHEEKS LACEY arms and legs Arthralgias in older patient Can cause fetal death in 1st trimester
Treatment for Erythema Infectiosum?
What is Roseola?
AKA Exanthem Subitum Caused by human herpesvirus 6 (HHV-6) Occurs in infants ages 6 months - 3 yo
What are clinical features of Roseola?
High, abrupt FEVER--->febrile seizures. Fever lasts 3-7 days. Rash on face, neck, arms, legs (pinkish-red flat or raised rash which turn white when touched) Defervescence (fever goes away) occurs before rash appears
What is Varicella?
AKA Chicken Pox Caused by Varicella Zoster
Clinical features of Varicella?
Vesicular rash (DEW DROP ON A ROSE PETAL) which starts on head, neck, trunk, and spreads Lesions appear in crops which crust after 3-5 days. Child is contagious for 1 week
What are complications of Varicella?
How do you treat Varicella?
Symptomatic tx NO ASA! Consider Acyclovir in teens
When can a child go back to school with Varicella?
Once lesions have crusted over and they are afebrile
What is Molluscum contagiosum?
A self-limited epidermal viral infection caused by the Pox virus and spread by skin to skin contact. Common in children.
What are clinical features of molluscum contagiousum?
Smooth firm dome shaped WAXY/pearly papules with central UMBILICATION Very ITCHY Multiple scattered lesions up to 100 on trunk, axilla Some crust and can get infected In adults they are usually in groin and lower abdomen
What is a complication of Molluscum?
Scratching can lead to secondary bacterial infection
"Honey colored crust" Erythematous macules, vesicles, bullae Often occurs in pre-existing skin conditions such as eczema
How do you treat Impetigo?
For Non-bullous: 2% Mupirocin and oral antibiotics For Bullous: Oral abx (can return to school after being on abx for 24 hours)
What is the pathophysiology of burns?
Leads to direct injury of skin and then inflammatory response Loss of barrier leads to fluids out and bacteria in There can be pulmonary damage which leads to inhalation of CO and other particulate matter
How do you determine severity of burns?
% of skin burned Depth
What is the Rule of 9's?
Head and neck - 9% Each arm - 9% Each leg - 18% Anterior trunk - 18% Posterior trunk - 18% Perineum - 1%
What are characteristics of first degree burn?
Red, blanches, painful No blister Minimal tissue destruction Most common cause: Sunburn Heals in 7-10 days No scarring
How do you treat 1st degree burn?
Hydrate Aloe Ibuprofen
What are characteristics of second degree superficial burns?
Red, painful Wet with blisters Most common cause: Scalding Heals 14-21 days May or may not have scarring
What are characteristics of second degree deep burns?
White and dry Tender with or without blisters Most common cause: Hot liquid, steam, flame Heals 14-21 days Some scar May need graft
What are characteristics of third degree burns?
Charred, pearly white Hallmark: Painless because of destroyed skin layer and nerve endings Most common cause: Grease, steam, flame, high voltage
How do you treat third degree burns?
What are characteristics of fourth burns?
Damage to fascia, muscle, bone Tissue is necrotic Most common causes: Hot and heavy objects (molten metal, extended exposure, electrical injuries)
What is considered a major burn in adults? Peds?
25% adults 15% peds
What is referral criteria for transfer to a burn center?
Second degree with >15% of BSA (or >10% for high risk patients) Third degree with >5% BSA Concomitant trauma Comorbid conditions Burns on face, hands, feet, genitals, or major joints Circumferential chest or extremity burn Electrical, chemical, inhalation burn Severe drug reaction (treated just like burns)
How do you manage acute burns?
100% O2 with pulse Ox Early intubation with any signs of inhalation injury Determine tetanus status Fluid resusictation for all burns >20% Foley NG/OG tube Prevent hypothermia Silvadene
3-4cc of LR x Kg x BSA 1/2 given in first 8 hours Last 1/2 given over 16 hours
What are the 8 types of fungal skin infections? Which is the most common?
Tinea pedis - most common Tinea unguium (onychomycosis) Tinea corporis Tinea cruris Tinea capitis Tinea versicolor Tinea manuum Tinea barbae
What test is used to identify dermatophyte infection?
Chronic infection caused by Malassezia furfur, a yeast colonizer of skin.
What are predisposing factors for tinea versicolor?
Warm climates Excessive sweating Oily skin
Clinical features of tinea versicolor?
Hypo- or hyperpigmented macules that do not tan in areas of overgrowth
What is the characteristic finding of tinea versicolor on a KOH prep?
"Spaghetti and meatballs" - round yeast, elongated hyphae
Tx for tinea versicolor?
Daily applications of selenium sulfide shampoo from neck to waist. Shampoo is left on skin for 15 min for one week
What are signs/symptoms of tinea capitis?
Seen on head/scalp. Can be asymptomatic or inflammatory alopecia (ectothrix) Broken hair shafts are seen as BLACK DOTS (endothrix) A KERION (nodular swelling) can appear. Common in infants, children, adolescents
How do you treat tinea capitis?
Oral antifungals (Lamisil, Griseofulvin) For Kerion: Hot compresses, Griseofulvin, Prednisone, Erythromycin, or Keflex
What are signs/symptoms of tinea corporis ("ringworm")?
Annular scaly patch with central clearing, red papules and/or plaques on the body or scalp Enlarged border with hypo or hyperpigmentation May be pruritic
What are risk factors for tinea corporis?
Contact with human/animal that may have ringworm.
How do you treat tinea corporis?
If just a few lesions: Antifungal BID for 4 weeks If multiple lesions: Griseofulvin for 2-4 weeks (or Lamisil or Sporonox)
Athlete's foot Fungal infection of feet Worse hot weather, boots, barefoot
Jock itch Fungal infection of groin, pubic region, thighs
Yeast/fungus infection of nail
What are Verrucae?
Common warts, caused by HPV Hands, fingers, palms Firm, elevated, rough papules 1-10mm with grayish rough surface Tiny black dots are thrombosed dilated capillaries Nail biters often get periungal warts, and on lips/tongue
What is Urticaria?
Group of disorders that have many causes. Most common causes include food or drug allergies, heat/cold, stress, infection. IgE mediated
What is the pathophysiology of urticaria?
Caused by release of histamines, bradykinen, kallikrein, and other vasoactive substances from mast cells and basophils in the skin. Causes small blood vessels to leak and results in intradermal edema.
How do you treat urticaria?
Cause should be eliminated H1 antihistamine administered (Diphenhydramine, Hydroxyzine, fexofenadine, cetirizine) H2 antihistamine (famotidine or ranitidine) if not responsive to H1. Give EpiPen if there is concern for anaphylaxis
Exanthematous Drug Reactions
Mimics measles like viral exanthem-symmetric brightly erythematous macules and papules, discrete and confluent Systemic involvement is low "Morbilliform or maculopapular drug reaction MC type of drug reaction!!
Pustular Drug Eruption
Acne like eruption with no comedones-can occur on arms/legs Generalized eruption - febrile, leukocytosis Caused by drugs
Drug Induced Urticaria
IgE mediated-after sensitiziation occurs 7-14 days, if previously sensitized can occur in minutes Immune complex mediated - 7-10 days to react, up to 28 days NSAIDs - After drug administration 20-30 min
Fixed Drug Eruption
Drug rxn occuring in solitary erythematous patch, plaque, erosion, or bullae Upon rechallenge still breaks out at same site
Drug Hypersensitivity Syndrome
Drug reaction occurring in the first 2 months after initiation of drug Morbilliform drug eruption, facial edema Symmetric distribution trunk/extremities