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Bites and Stings. Question 5. The most effective treatment to eliminate the lesions seen here: A Topical steroids B Oral antibiotics C Treatment of home for fleas D 5% Permethrin cream to all household members E Oral antihistamines. Bites and Stings.
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Question 5 • The most effective treatment to eliminate the lesions seen here: • A Topical steroids • B Oral antibiotics • C Treatment of home for fleas • D 5% Permethrin cream to all household members • E Oral antihistamines
Bites and Stings • Think about distribution (exposure) • Bites on face may be atypical • Red • Pruritic • Soft and nontender • Intense, hemorrhagic reaction possible • Fleas: some members of household “spared” • Clusters of 3 • Grass or sand mites: localized blisters
Spider Bite • More intense reaction • Erythema and induration • Ecchymotic • Painful • Pruritic • Vesciculate • Central necrosis with eschar • Brown Recluse
Hymenoptera Stings • Local pain, erythema, edema within 2hrs • Honey Bee • Stinger in skin • Releases venom for an hour • Scrape horizontally with fingernail or card
Hymenoptera Stings • Late onset edema • Peak 48-72hrs • Delayed hypersensitivity • Pruritic, painful • Treatment • Paste of meat tenderizer and water • Symptomatic treatment • Risk of anaphylaxis • Known history • Mastocytosis • Education on avoidance • EpiPen
PapularUrticaria • Timing • Young children • Chronic/recurrent • Description • Highly pruritic papules and wheals • Central punctum • Vesiculate centrally • 3-10mm diameter • Resolution: • central crust with collarette of scale • After 4-6wks: target-shaped macule • Linear or triangular clusters • Exposed areas
PapularUrticaria • Cause • Hypersensitivity to fleas, bedbugs, mosquitoes • Fleas and bedbugs are not seasonal • Only youngest child in family may be affected • >1y/o • May experience “reactivation” • New bites incite delayed hypersensitivity at old sites
PapularUrticaria • Treatment • Identification and avoidance of insect • Repellent • Topical steroids • Oral antihistamines • Good hygiene (secondary infections)
Scabies • Cause • Mite: Acarusscabiei • Burrows beneath skin • Hypersensitivity reaction • Timing • 4-6 wks after initial contact • Description • Intensely pruritic papules, vesicles, pustules, linear burrows • fingers/ webs of toes, flexor regions, nipples, waist, groin/buttocks, palms/soles • Infants: intense and persistent nodular reaction
Scabies • Excoriation and secondary infection • Diagnosis • Clinical • Skin scrapings: mite, eggs, feces • From linear burrow (black speck) • Treatment • 5% permethrin (Elimite) • All household members • Wash all linens • Repeat 1 wk later
Lice • Crab lice (Phthirus pubis) • Sexually transmitted • Eyelashes and pubic hair • Bites • Bluish, pruritic papules: lower abd and upper thighs • Intense pruritis • Children • Scalp or eyelashes
Lice • Body lice (pediculushumanuscorporis) • Bedding or clothing • Bites • Urticarial papules • Waist, neck, shoulders, axillae • Excoriations/ secondary infection
Lice • Head Lice (pediculushumanuscapitis) • Most common • Excoriations of scalp and neck • Occipital adenopathy • Nits: oval, white 0.5mm dot glued to hairshaft • Above and behind ears • Nonviable shells may remain attached after treatment
Lice • Treatment: • Pediculicide topically (all household members) • Permethrin cream • Malathion lotion (second line…flammable) • Lindane: contraindicated in young… neurotoxic • Cleaning of linens/clothing • Nits: • Diluted vinegar rinse • Fine-toothed comb
Acne • Acne vulgaris • Disorder of pilosebaceous apparatus • Cause: Unknown • Abnormal follicular keratinization • Driven by androgens • Propionibacterium acnes • Treatment • Topical retinoic acid, benzoyl peroxide, abx • Severe: oral abx with topical agents
Question 6 • The most reliable way to distinguish these lesions from other lesions frequently seen on the sole of the foot: • A Black dots indicate corns that have received trauma • B Interruption of dermatoglyphics indicate plantar warts • C Superficial scaling indicates callus formation • D Boggy texture indicates plantar warts
Warts • HPV • Fingers, hands, feet • Plantar wart: Larger than appearance • Painful w walking • Interrupts dermatoglyphics • Incubation 1-6mos • Disappear spontaneously over 5yrs • Local trauma: inoculation of virus • Periungual common
Warts • Characteristic appearance • Black dots (thrombosed capillaries) • Condylomataacuminata • Anogenital warts • Consider sexual abuse • Controversial <age 3 (vertically acquired) • Treatment • Duct tape • Salicylic acid
MolluscumContagiosum • Pox virus • Description: • Dome-shaped papules with waxy surface • Single or multiple • May be pruritic • 5mm • Location: trunk, face, axillae, genital area • Spread by scratching (linear)
MolluscumContagiosum • Curdlike core can be expressed from center • Course: spontaneous remission 2-3yrs • Treatment • Watchful waiting • Curetting after topical anesthetic • Especially in poorly controlled eczema
Cutaneousmastocytosis • Pathological proliferation of mast cells in skin • Other organs involved as well • Darier sign • When lesion (or skin) rubbed, urticaria develops • Histamine release following trauma to superficial mast cells • May form blisters • 75% identified by age 2
Cutaneousmastocytosis • Urticaria pigmentosa (most common form) • Oval or round red-brown • Macules, papules, plaques • Solitary or innumerable • Resemble • Nevi, pigmentary alteration, CALMs • May be associated with GI symptoms • Hypotension in severe cases
Cutaneousmastocytosis • Other organ systems can be affected • Treatment • Usually resolves in childhood • Symptomatic treatment • Antihistamines • Immunosuppresants in severe cases • Extensive workup rarely needed
Juvenile Xanthogranuloma • AKA: Nevoxanthoendothelioma • Present at birth (w/in 1st year) • Grow slowly and become more yellow • Benign proliferation of non-Langerhans cell histiocytes • Brown to yellow color: lipid-laden histiocytes • Benign
Juvenile Xanthogranuloma • Primarily in whites • Usually solitary nodular lesion • Multiple small papular lesions possible • 4% extracutaneous • Iris • Other locations • Associations/Complications • Glaucoma • Myelomonocytic leukemia • NontraumaticHyphema
Juvenile Xanthogranuloma • No specific gene defect • NF-1 • Urticariapigmentosa • Niemann-Pick • Treatment • Watchful waiting • Resolve 5y/o • Surgical excision • Steroids +/- chemo
Job Syndrome • Abnormal immunity • T-Cells, Neutrophils • High IgE and eosinophils • Chromosome q4 • AD • Variable expressivity
Job Syndrome • Description • Pruritic • S. aureussuperinfection • Weeping, crusting, cutaneous abscesses • Abscesses (little pain and inflammation) • Mucocutaneouscandidiasis • Timing • Shortly after birth
Job Syndrome • Course • Recurrent focal bacterial infections • Decreased bone density with multiple fractures • Little pain • With age: scoliosis and coarsening of facial features • Treatment • Control infections