199 terms

Peds Blueprint: Dermatology


Terms in this set (...)

What is a macule?
Flat lesion, <1cm
What is a patch?
Flat lesion, >1cm
What is a papule?
Solid, elevated lesion, <.5cm
What is a nodule?
Solid, elevated lesion, >.5cm
What is a plaque?
Plateau like lesion, >1cm
What is a tumor?
Large nodule, >2cm
What is a wheal?
Transient superficial edema (urticaria, hives)
What is a vesicle?
Circumscribed, elevated lesion containing serous fluid, <.5cm
What is a bulla?
Circumscribed, elecvated lesion containing serous fluid, >.5cm
What is petechiae?
Hemorrhagic spots that cannot be blanched
What is a crust?
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?
Linear crack
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.
Common skin conditions of the newborn
Neonatal acne
Neonatal cephalic pustulosis
Erythema toxicum
Miliaria rubra
Seborrheic dermatitis
Mongolian spot
Nevus simplex (stork bite)
Vernix caseosa (greasy covering)
Lanugo (fine hairs)
Eczematous eruptions
Diaper dermatitis
Contact dermatitis
Atopic dermatitis
Seborrheic dermatitis
Perioral dermatitis
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?
May also have:
+/- vesciulation
Xerosis (dry skin)
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
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
What are some common chemicals that cause irritant CD?
Soaps, cleaners, solvents, detergents
What are some common allergens that cause allergic CD?
Metal salts
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)?
Low potency steroids
Ketoconazole shampoo/foam
Immunomodulators (Tacrolimus, Pimecrolimus)
Blepharitis- baby shampoo
In the treatment of dandruff, shampoos with which two elements has been shown beneficial in acute flare ups?
Selenium and zinc
What is atopic dermatitis?
"The itch that rashes"
AKA Eczema
Chronic, itching, relapsing skin disorder that leads to scaly excoriated erythematous patches. Often there is lichenification and secondary infection
What causes atopic dermatitis?
Type I immunoglobulin E-mediated hypersensitivity reaction
+ family Hx
What areas of the body does atopic dermatitis usually affect?
Flexural areas: antecubital and popliteal fossa, neck, eyelids, wrists, ankles
What do patients with atopic dermatitis tend to also have?
Allergic rhinitis and asthma (Atopic triad)
When is atopic dermatitis often diagnosed?
First 2 months of life-1 yo
What bacteria usually causes secondary infections in atopic dermatitis?
S. aureus
How do you diagnose atopic dermatitis?
Clinical diagnosis
What are exacerbating factors of atopic dermatitis?
Barrier disruption - caused by frequent bathing
Seasons - worse in winter
Clothing - wool, nylon, fur are irritating
Emotional stress
What are associated features of atopic dermatitis?
Mild facial pallor
Eyelid pleats
Keratosis pilaris
Pityriasis alba - white patches on cheeks and upper arms
Increased palmar creases
Ichthyosis vulgaris - extremely dry skin
How do you treat mild atopic dermatitis?
Low-mid potency topical steroids
Gentle "soap-free" cleansers
Limit baths
Antibiotics for 2ndary infections
Education: avoid low humidity, sweating, wool, minimize stress, etc
What is the mainstay of treatment of atopic dermatitis?
Topical steroids
How do you treat moderate-severe atopic dermatitis? What is the major AE?
Immunomodulator creams (Tacrolimus, pimecrolimus)
AE: Black box warning for lymphoma (rare)
What is perioral dermatitis?
Dermatitis around the mouth which occurs mostly in young women and often there is a history of prior topical steroid use.
What are characteristics of perioral dermatitis?
Pauplopustules form on erythematous bases and may become confluent with plaques and scales.
Satellite lesions are common
How do you treat perioral dermatitis?
Avoid topical steroids - will make worse
Topical antibiotics (metronidazole, erythromycin, doxy, mino, or tetracycline)
Untreated lesions will fluctuate over time, similar to rosacea
Papulosquamous disease
Drug eruptions
Lichen planus
Pityriasis rosea
What is Lichen planus (LP)?
An acute or chronic inflammatory disorder that occurs in adults (age 30-60). Females are more affected than males.
What causes LP?
Possibly drugs, metals, infection
What are clinical features of LP?
Flat topped, shiny, polygonal papules that are violet with white lines ("Wickham's striae").
Can affect oral mucosa, scalp (alopecia), nail, skin lesions, genital lesions.
Koebner phenomenon is seen.
All patients with LP should be screened for what disease state?
Hep C
How do you treat LP?
Topical steroids
IL steroids
Systemic therapy: Cyclosporin, Oral prednisone, retinoids
What are the 4 P's of LP?
What is Pityriasis Rosea?
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?
Psoriatic erythroderma
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?
Clinical diagnosis
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
Desquamation disease
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.
What are three common causes of EM?
1.Drugs (sulfonamides, phenytoin, barbiturates, PCN, allopurinol)
2. Infections (HSV, Mycoplasma)
3. Idiopathic: 50% of cases
What is the principal risk factors for EM?
HSV infection!!
Previous history of EM
Who is most affected by EM?
Patients <20
What are clinical features of EM?
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?
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
What are some drugs that cause SJS?
Valproic acid
How do you treat SJS?
Stop offending drug
Supportive care: Replace fluids and electrolytes, high caloric supplementation
Prevent sepsis
SJS is thought to be a severe variant of ___. TEN is thought to be a severe variant of ___.
What is Toxic Epidermal Necrolysis (TEN)?
Progression of SJS to full thickness skin detachment. >30% skin loss
What are clinical features of TEN?
High fever
Nikolsky sign
Diffuse erythema
Necrotic epidermis
Sheetlike loss of epidermis
High mortality
How do you treat TEN?
Like a burn victim
Mucosal erosion and epidermal detachment of <10% is classified as what?
Skin loss between 10-30% is considered what?
Epidermal detachment >30% is classified as what?
Best place to treat SJS/TEN?
Burn unit
Organism - Pediculosis humanus and Pthirius pubis-1-3mm long flattened lice with 2 pairs of legs and claws
Mite Sarcoptes scabiei
Burrow into skin and deposit eggs which mature in 10-14 days
Highly contagious because infested humans do not manifest sign or sx for 3-4 weeks
SEVERE ITCH, worse at night
Where does Scabies usually distribute?
Axilla, umbilicus, groin, penis, instep of foot, web spaces, fingers, and toes
In infants face and scalp can be involved
How do you treat scabies?
PERMETHRIN applied from chin to bottom of feet and left overnight (8 hours) then washed off in morning. Repeat tx in 7 days.
What is Alopecia?
Hair loss. Can be male pattern baldness (androgenetic alopecia) or alopecia areata
What conditions are associated with alopecia areata?
Pernicious anemia
Addison disease
Treatment for lice?
Tx: PERMETHRIN (Elimite 5%) with retreatment in 7-10 days
How do you treat alopecia areata?
May respond to steroids
Acneiform lesions
Acne vulgaris
What is Acne vulgaris?
Inflammation of the pilosebaceous units of certain body areas like face, trunk, and rarely buttocks. It manifests as comedones, papulopustules, or nodules and cysts. Scars may follow
What are the hallmark lesions of acne?
Who is more at risk for Acne?
Adolescents and males
What is the pathophysiology of acne?
Plugged follicles, retained sebum, bacterial overgrowth, and release of fatty acids. Androgens stimulate sebum production
What are the 3 main causes of Acne?
Follicular hyperkeratinization (plugs)
Propionobacterium acnes (bugs) AKA "P acne
What are clinical features of acne?
Comedones - either open (blackheads), closed (whiteheads), or noninflammatory
Sinus tracts with nodular acne
What are the 4 grades of Acne classification?
Grade 1 - Comedones (non-inflammatory)
Grade 2 - Comedones, early papules and pustules
Grade 3 - Comedones, papules, pustules, inflammation, erythema, nodules, truncal involvement
Grade 4 - Cystic and severe
What are some labs with acne if an endocrine disorder is suspected?
Anyone with Acne needs a...
A retinoid!
What are thee retinoids available to treat Acne?
Adapelene (Differin)
Tretinoin (Retin-A)
Tazarotene (Tazorac)
How do you treat mild acne?
Keep affected area clean
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?
Females 30-50
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?
S. aureus
What is the cause of folliculitis seen in hot tub users?
What pathogens cause the most pediatric infections?
What are the 6 childhood exanthems (rash-causing diseases)?
Measles (Rubeola)
Scarlet fever
German measles (Rubella)
Filatov-Dukes disease
Fifth disease (Erythema Infectiosum)
What are clinical features of Measles?
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?
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?
Symptomatic treatment
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)
LACEY arms and legs
Arthralgias in older patient
Can cause fetal death in 1st trimester
Treatment for Erythema Infectiosum?
Symptomatic tx
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
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
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
How do you treat Molluscum?
Acid/exfoliative peel
What is Impetigo?
An acute, contagious superficial skin infection
What causes impetigo?
Staph aureus (50-70%)
What are clinical features of Impetigo?
"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
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?
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?
Auto grafting
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%
NG/OG tube
Prevent hypothermia
Parkland formula
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?
KOH prep
Tinea versicolor
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)
Tinea pedis
Athlete's foot
Fungal infection of feet
Worse hot weather, boots, barefoot
Tinea cruris
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