Erin Pratt

 Type III Hypersensitivity reaction to proteins in antiserum or antibiotics  Si/sx: fever (prior to rash), malaise, arthralgias, GI issues, LAD and urticarial rash  Characteristic serpiginous erythematous and purpuric eruptions on hands and feet at junction of plantar and palmar skin

 Common drugs we use: Cephalosporins (Ceclor, Keflex), Bactrim, Captopril, PCN, Dilantin  Treatment:  D/C offending agents  Symptomatic antihistamines, pain relievers, steroids  Resolves spontaneously

 Acarius scabiei  Highly contagious direct contact with infested human  Hypersensitivity reaction to mite  Characteristic eruption 4-6 weeks after contact pruritic papules, vesicles, pustules and linear burrows  Linear burrow, made by female mite, is pathognomonic  Areas: finger and toe webs, axillae, flexor surfaces of wrists and elbows, around nipples and waist, and groin and buttocks  Infants and Toddlers: head, neck, trunk, palms, soles, dorsa and instep, lateral wrist (also more prone to nodular reaction)

Diagnosis can be masked by excoriation, secondary infection or secondary eczematous eruption Consider scabies if no h/o atopic derm but severe pruritus and recent onset of eczema type rash Look to the distribution to help with diagnosis

 Diagnosis: skin scraping with mineral oil (burrows or papules)  Treatment: Elimite (Permethrin 5% cream) apply head to toe at night and wash off in am or Lindane lotion  May have to repeat treatment  Can use oral antipruritics or topical steroids for secondary reactions

 Acne vulgaris disorder of pilosebaceous apparatus  Areas: face, back and upper chest  As early as 8 yrs but typically during puberty  Androgens stimulate sebaceous gland differentiation and growth and production of sebum  Exact pathogenesis is unknown

 Closed comedones (blackheads)/ Open comedones (whiteheads)  Proliferation of Propionibacterium acnes in noninflammatory comedones and rupture of the contents into the dermis may lead to inflammatory papules, pustules and cysts  Cystic acne frequently leads to scarring

 Treatment:  Mild to Mod: topical retinoic acid, benzoyl peroxide, and anitbiotics  Mod to Severe: oral antibiotics with topical agents  Oral 13-cis retinoic acid or isotretinoin should be reserved for severe, scarring cystic acne not responding to conservative measures above

 Poxvirus  Sharply circumscribed single or multiple skin-colored, dome-shaped papules with waxy surface. Usually umbilicated center although can have protruding white center.  Areas: trunk, axillae, face, and genitals  Contagious, spread by scratching so often in linear pattern  Curdlike core often expressed (typical molluscum bodies under microscope)  Treatment: sponateous remission; Can curette the core or use blistering agent followed by plastic tape for three days

 Repetitive “hair pulling” or twisting  Short broken-off hairs with different lengths in adjacent areas often in broad, linear bands  Areas: vertex or sides of scalp, eyebrows and eyelashes  Often caused by situational stress or habitual behavior in school-aged or adolescnets; also seen in psych patients  Often denied by patient and parents  Distinguished from alopecias by no areas of complete baldness and hair follicles not easily removed

 Trichophyton tonsurans causes 95%of scalp ringworms; Microsporum canis (dog/cat ringworm)  Endemic in school-aged black children  Diagnosis: KOH exam of hair pulled not cut to look at root; Wood light only floresces M. canis not T. tonsurans  Several presentations:

1. MILD ERYTHEMA AND SCALING OF SCALP WITH PARTIAL ALOPECIA 2. ENDOTHRIX INVADES HAIR CAUSING BREAKAGE IN “SALT-AND-PEPPER” APPEARANCE

3. ANNULAR LESION SIMULATING TINEA CORPORIS 4. ERYTHEMA, EDEMA AND PUSTULAR FORMATION FROM SENSITIZATION RUPTURES CAUSING GOLDEN CRUSTS SIMULATING IMPETIGO

5. PATCHES OF HEAPED UP SCALE IN ASSOCIATION WITH SMALL PUSTULES 6. KERION RAISED, TENDER, BOGGY PLAQUES OR MASSES WITH PUSTULES SIMULATING AN ABSCESS

 Treatment:  Topicals do not penetrate deeply enough  Griseofulvin or ketoconazole over 2-4 months  Concurrent use of Selenium sulfide 2.5% reduces spore formation and shedding  High risk of recurrence