Lichenoid eruptions

Lichen Planus Description Flat-topped, polygonal, violaceous papules and plaques Wickham’s striae: fine lacy pattern Dorsal surface of extremities Koebner phenomenon at sites of trauma Nail dystrophy Oral mucosa: lacy white plaques

Lichen Planus Treatment Course Topical steroids Prolonged period of hyperpigmentation can be expected

Lichen Striatus Description Location Flat-topped papules appear abruptly Erythematous or hypopigmented Surfaces with fine scale Linear or swirled distribution (along skin lines of Blaschko) Nail dystrophy Location Extremeties, neck, upper back

Lichen Striatus Timing Course Peak in school-age children Spontaneous resolution 1-2yrs

Vesiculopustular disorders

Tzanck Smear Tells you that it’s a viral lesion Multinucleated giant cell Not specific to type of virus Outdated Use DFA, PCR, or Viral culture

Blistering Distal Dactylitis Superficial bacterial skin infection Cause: GAS, GBS, S.aureus Location Tips of pads of fingers/toes Description Tense blisters, 5-10mm Filled with thin, purulent fluid Narrow erythematous rim Thick crust upon rupture

Question 3 Which is true of the condition pictured? A Use of systemic steroids may improve survival B Systemic antibiotics with G+ coverage are the mainstay of treatment C Permanent sequelae may include visual impairment D Nikolsky’s sign is negative Answer: C TEN

Reactive erythemas

Erythema Nodosum Description Location Symmetrical, red, tender nodules 1-5cm Location Pretibial Hypersensitivity reaction, associated with: Strep Sarcoid Ulcerative colitis TB Other bacterial/fungal infxn Oral contraceptives and other meds

Erythema Nodosum Timing/Course Description Treatment >10y/o Lasts 2-6wks Often recurs Description Red, tender, slightly elevated nodules Indurated SQ plaques Brownish-red or purplish-red hue Shins most common site Treatment Tx underlying cause Pain: NSAIDS and rest

Urticaria Aka “Hives” “Welts” Course Description Sudden onset Transient Lasts 1-24hrs Description Well-demarcated intensely pruritic Appear to migrate May coalesce White/red “halo”

Urticaria Cause: can be IgE or complement mediated Acute (<6wks) Acute infections (strep, mono) Foods Drugs Insect bites Contact or inhaled allergen Chronic (>6wks) Occult infection Hep B Connective tissue dz

Question 4 This child has mild edema of hand/feet and painful migratory periarticular swelling of wrists and ankles. The most likely etiology is: A Staph Scalded Skin Syndrome B Henoch-Schonlein Purpura C Hemolytic Uremic Syndrome D Interstitial nephritis as part of a reaction to medications E Serum Sickness-Like Reaction Answer: E

Serum Sickness-Like Reaction Type III reaction: Immune-Complex Deposition Symptoms Urticarial lesions Relatively nonpruritic Target or serpiginous Periarticular swelling Migratory Stocking-glove angioedema Painful Facial edema Fever

Serum Sickness-Like Reaction Triggers URI Meds Sulfa Cefaclor Minocycline PCN Course Wax and wane over 1-3wks

Erythema Multiforme Hypersensitivity syndrome Causes Recurrent EM Drugs, viruses, bacteria, foods, immunizations Connective tissue dz Recurrent EM Recurrent HSV infxn Location Any part of body Commonly: palms/soles, arms/legs

Erythema Multiforme Description Symmetrical Dusky red macules – evolve into iris or target-shaped lesions Center of target may be blue, violaceous, or white Vescicles or bullae may develop Center or ring of target May appear as diffuse urticaria initially Non-pruritic, may be painful

Erythema Multiforme Course Crops last 1-3 wks Self limited ?Mild systemic symptoms? Low grade fever Malaise Myalgia Mucous membranes spared Or mildly involved

SJS / TEN Epidermal and mucous membrane necrosis and sloughing Cleavage beneath basment membrane zone Full-thickness sloughing SJS: <30% BSA TEN: >30% BSA Cause: hypersensitivity, viral infxn, connective tissue dz, malignancy

SJS/TEN Complications Ophtho: Corneal scarring Lid scarring: ectropion FEN Dehydration Malnutrition Electrolyte imbalance ID Superficial infection Sepsis Death

SJS / TEN Treatment Differentiate from SSSS SSSS IVIG Steroids relatively contraindicated GI symptoms Immune suppression Differentiate from SSSS SSSS Bullae more thin-walled Mucous membranes red, but do not slough

Morbilliform Drug Eruption 75% of all cutaneous drug reactions Description Erythematous macules and papules Range from fine to blotchy Eruption 5-14days after starting med Face/Trunk  extremities May become confluent Resolves over 1-2 wks May see mild purpura, desquamation

Fixed drug eruption Recur at same localized site following reexposure to offending drug Target and bullous lesions Resemble erythema multiforme Morphologically and histologically (only localized)

Vasculitis

Henoch-Schonlein Purpura Classic Tetrad Palpable purpura Without thrombocytopenia or coagulopathy Present in almost all patients Arthritis/Arthralgia 75% Abdominal Pain (May have hematochezia) 50% Intussussception (ileo-ileal) Renal Disease (Mild) 21-54% Not all symptoms must be present for diagnosis Takes days to weeks to develop May present as abd pain or joint complaints* May recur

Henoch-Schonlein Purpura Diffuse Vasculitis Histo: immune-complex deposition in capillaries Leukocytic vasculitis in skin Treatment Supportive May use steroids if severe

Henoch-Schonlein Purpura DIFFERENTIATE FROM HUS Hemolytic Uremic Syndrome More toxic Renal involvement more severe (dialysis) Hemolytic: anemia, thrombocytopenia More severe neuro manifestations