M3: skin Flashcards
HSV
type 1 affects oral mucosa, pharynx, lips, eyes: cold sore or fever blisters. often 6mo-5 years. type 2 is often genital and congenitally transferred; but both can be in both places. Herpetic whitlow on finger/thumb is swollen painful lesion with a red base and ulceration; occurs with thumb suckers. transmitted through contact through break in skin. incubation: 2-12 days. primary occur <5 years old, more painful/extensive, last longer. s/s: fever, malaise, sore throat, decreased fluid intake, painful. prodrome of burning, tingling, itching, paresthesia at site. communicable for 2 days to 2 weeks.
HSV s/s and diagnostics
Neo always symptomatic. disseminated around day 10-12 of life with MODS; 2/3 get encephalitis. half never get rash. CNS disease day 16-19 with seizures, lethargy/irritable, poor feeding. most get herpetic lesions. 1: gingivostomatitis, pharyngitis with grouped vesicles on red bacse that ulcerate and plaque; herpes labials: small, clear, tense vesicles with red base that weep/ulcerate > crust usually bilateral; herpetic whitlow. 2: grouped vesicopustules and ulceration with edema. regional lymphadenopathy. dx with viral cultures gold standard. can do DFA, ELISA, PCR with severe forms. differentials: pathos stomatitis, coxsackie virus, hand foot mouth varicella, impetigo, folliculitis, erythema multiform.
HSV treatment
Burrow solution compresses tid; acyclovir 20-40mg/kg/dose PO 5x/day for 5 days to alleviate s/s and shorten course for >2 years old. topical antivirals for genital >12 years old. Abx for secondary bacterial infection like mupirocin, EES, dicloxacillin. Oral anesthetics like viscous lidocaine or liquid Benadryl. antipyretic/analgesic/hydration/good oral hygiene. exclude from day care only with initial course and if uncontrolled secretions. recurrent, frequent, severe can be prophylactically treated for 6 mo. fever can be 4 days and can take 2 weeks to heal. (Neo’s often not treated prophylactically if mom has active RECURRENT genital infection, just closely monitor.)refer ocular involvement. women with HSV should have C-section.
Herpes zoster
varicella shingles. more common following mild infections before 1 year old and in immunocompromised. burning, stinging pain, tenderness to light touch, hyperesthesia, tingling; eruption by about 1 week. 2-3 clustered groups of macules/papules > vesicles on red base > pustular, rupture, ulcerate, crust. develop over 3-5 days and last 7-10 days. lesions develop for 1 week followed by crusting and healing in 2 weeks. postherpetic neuralgia is rare. follow dermatomes. lesions don’t cross midline*, sharp demarcation at midline with occasional contralateral involvement. may have lymphadenopathy.
Herpes zoster diagnostics/tx
Tzanck smear or viral culture. can do bacterial culture or gram stain. DFA stain. differentials HSV and impetigo. tx: burrow solution compresses did, warm/soothing baths, antihistamines, analgesics (no salicylates), ointment, acyclovir for immunocompromised/ocular herpes/Ramsay-Hunt; abx secondary infection (mupirocin/dicloxacillin); refer for eyes/forehead/nose involvement. contagious until lesions crust; if they can be covered, can still go to child care or school
HSV traumatic infection and meningoencephalitis
Over abrasion/lac etc. Fever, constitutional s/s, regional lymph node involvement. Meningoencephalitis: intermittent, non epidemic leading cause. diagnosis by brain biopsy. HSV meningitis alone is usually relatively benign and d/t HSV-2. Virus never goes away just goes dormant so recurrent infections are common.
Acne vulgaris
excess sebum, keratinous debris, bacteria accumulate > microcomedones (+/- inflammation). most common skin disorder. sebaceous follicles plug with keratinous material > anaerobic bacteria grow in follicle (esp. p. acnes and also staph and M. furor) > overproduction of sebum and androgen > expanded follicle > inflammation and pustules d/t bacteria. often starts with puberty, improves in summer and worsens with menses and stress. check family hx, puberty stage, face/hair products, medications like contraceptives/abx/steroids, previous acne treatment, sports participation, jobs, etc.
Acne s/s
microcomedone: follicular plug d/t obstruction, on face and trunk. open comedone (blackhead) non inflammatory lesion/papule that is firm d/t blockage at mouth of follicle. closed comedones (Whitehead) semisoft d/t blockage at neck of follicle, precursor to inflammatory acne. inflammatory lesions secondary to rupture of lesions and include papule, pustules, excoriations, lesions, nodules, cysts, scars, sinus tracts. Comedonal acne, or nodulocystic acne. Also frictional, pomadal (temple/forehead d/t makeup), athletic, and hormonal.
Acne tx
reduce excess sebum, counteract epithelial cell desquamation, decrease bacteria, prevent/decrease scarring. Topical keratolytic or comedolytic agents are first line. gels are strongest, creams least drying. start low and slow and increase as needed. start 3 nights/week and increase to nightly. 4-6 weeks needed to eval treatment. retinoids (tretinoin, adapalene, tazarotene) have keratolytic and antibacterial properties. can cause dryness, redness, irritation, scaling, sun sensitivity. first line: benzoyl peroxide or topical retinoid or combo for mild. Moderate: BP + abx/retinoid or oral abx with topical combo. severe: oral abx + topical combo or oral isotretinoin. can consider oral contraceptive or spironolactone.
Meds for acne
Tazarotene: daily use keratolytic. Acelaic acid: antibacterial/keratolytic good for sensitive/dark skin. BP: antimicrobial with comedolytic/anti-inflammatory effects. decreases abx resistance in combo with abx. topical Clinda: don’t use within 30 min shaving; can also do EES. oral abx like tetracyclines 3-4 weeks up to 6months max. take with water not with food for tetracycline; EES with food; minocycline without dairy, and can cause blue-black discoloration in scars, photosensitivity, and hypersensitivity. doxy with food but high photosensitivity. oral retinoids for severe recalcitrant nodulocystic acne: isotretinoin (not with pregnancy). usual 20 weeks course, must monitor LFTs, cholesterol, triglycerides, HCG, UA monthly. Hormonal therapy. Noncomedogenic moisturizers.
Acne education
worsens before improving. wash face bid with mild soap. don’t scrub, rub, pick, or squeeze. no comedones extractors; use hot soaks. noncomedogenic products, avoid aggravating substances or factors like stress, humidity, frying oil/grease. watch food. f/u q4-6 weeks until controlled, which is when only a few new lesions appear q2 weeks. infantile acne watch and gentle cleaning. in mild comedonal, topical tretinoin. BP mild inflammatory acne.
Urticaria/angioedema
hypersensitivity reactions usually IgE mediated. urticaria just dermis; angioedema deeper dermis and subQ tissue. vasodilation and increased vascular permeability > redness and wheal. fast onset. can be reaction to foods, antigens like latex/chemicals/fish, response to infections, cholinergic response to physical stimuli like heat/cold/water/sun/tight clothing/ stress; reaction to drugs, genetic, with inflammatory systemic disease, immunologic, or idiopathic. 1/2 patients with urticaria have angioedema. acute <6 weeks, chronic over. angioedema tends to involve face, hands, feet, gradual and often d/t meds.
urticaria/angioedema s/s
family hx, intense itching/scratching, ingestion of trigger foods/meds, injection of diagnostic agents/vaccine/insect venom/blood; infections, inhalation of dander/pollen/dust/smoke; flea bites; cold/heat/exercise/sun/water/pressure/vibration. Urticaria: red, annular, raised wheels/welts with pale centers from 2mm-several cm, of various shapes. appear suddenly and fade in 20 min to 24 hours, if lasting >48 hr not urticaria. blanches with pressure, intensifies with heat, wheals after rubbing skin. often papular. large blotchy red lesions. angioedema is asymmetric, localized, nondependent, transient edema that’s less itchy but can be dangerous.
urticaria/angioedema dx/tx
if fever, do work up. differentials: contact dermatitis, atopic dermatitis, scabies, erythema multiform; vasculitis, psoriasis, arthritis. tx: remove offending substance, stop abx. test for dermatographism by stroking skin, cholinergic by applying heat, cold urticaria with cold packs, pressure by applying weighted bands, water by applying wet compresses. oral antihistamines like Benadryl. topical antipruritics, aqueous epi. prednisone if refractory. f/u if no improvement in 24-48 hr. refer chronic. episodes kid after first episode or with recurrent.
angioedema/urticaria education
usually resolves by 2 days, papular urticaria hypersensitivity declines within 6-12 months; physical urticarias last up to 4 years most cases. papular urticaria declines within 1 year. sometimes blue-brown lesions last. avoid allergens; wear medical bracelet; keep epi kit.
