Scabies. Scabies 10/22/2012. What s Bugging You? Common Cutaneous Infections and Infestations in Kids

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1 What s Bugging You? Common Cutaneous Infections and Infestations in Kids Andrea L. Zaenglein, MD Associate Professor of Dermatology and Pediatrics Penn State/ Hershey Medical Center Touching the Future of Children October 29, 2012 Scabies Latin: scabere, "to scratch" Sarcoptes scabiei Very pruritic Always think scabies when itch keeping them up at night Scabies Permethrin 5% cream 2 mo and older Get under fingernails! Ivermectin For resistant/ institutional cases >15kg 200 mcg/kg as a single dose; may need to repeat in days Others: Lindane, benzyl benzoate, sulfur 1

2 Bed Bugs Cimex lectularis Flat 5mm oval, brown, wingless insect (six legs) An adult bedbug can survive for 12 months without blood, up to 2 years in cooler environments Inhabit concealed dry hiding places Mattresses, floorboards, wallpaper Emerge only at night Can carry human diseases, but no transmission ever documented Porten M, Prose N. The return of the common bedbug. Pediatr Dermatol 2005;22: Chagas Disease American trypanosomiasis Flagellate protozoan Trypanosoma cruzi. Vector: Triatome reduviid Order Hemiptera (like bedbugs) Pronounced gastrocolic reflux Untreated affects heart/ GI Romana s sign Infectious feces gets into bite Papular Urticaria Hypersensitivity to bug bites CD4+ T cells Delayed type reaction Lasts months/ years Worse summer but year round Exposed areas Facial involvement uncommon 2

3 Papular Urticaria Rule out infestation Treatment: Oral antihistamine Strong topical steroid Bite prevention measures (long sleeves/ pants, DEET) Hernandez RG, Cohen BA. Insect bite induced hypersensitivity and the SCRATCH principles: a new approach to papular urticaria. Pediatrics Jul;118(1):e Skeeter Syndrome Localized allergic reaction to allergenic polypeptides in mosquito saliva Noninfectious cellulitis (looks like infectious cellulitis) 2 4 years old Simons FE, Peng Z. Skeeter syndrome. J Allergy Clin Immunol Sep;104(3 Pt 1): ourpreciousprincess.blogspot.com/2010/07/skeeter syndrome.html Dermatophyte Infections Tinea capitis T. tonsurans = most common, black dot M. canis = inflammatory, kerion Onychomycosis 4 types 1. Distal subungual most common, T. rubrum 2. White superficial T. mentagrophytes 3. Proximal subungual T. rubrum, HIV 4. Candidal chronic mucocandidiasis 3

4 Dermatophyte Infections 3 species: Microsporum, Trichophyton and Epidermophyton Tinea pedis and Tinea manum T. rubrum = noninflammatory, moccasin foot T. mentagrophytes = inflammatory One hand, two foot Tinea cruris T. rubrum, E. floccosum How do I decide what to use? Efficacy always systemic therapy Can use topical/shampoo as adjunct or to control for fomite sources of fungal reinfection Safety Cyclodextran in itraconazole liquid Pancreatic cancer in rats Griseofulvin, terbinafine, and fluconazole have good safety profiles Cost 4

5 Griseofulvin Formulations (microsized 125 mg, 250 mg) mg/kg/day (ultramicrosized) mg/kg/day (liquid 125mg/5ml) mg/kg/day Adverse reactions: granulocytopenia, decreased efficacy of OCPs Do not take if pregnant, liver disease, AIP Terbinafine Formulation 250 mg tablets 125mg/pk granules kg 62.5 mg/day x 4 wks kg 125 mg/day x 4 wks > 40kg 250 mg/day x 4 wks Adverse reactions: hepatoxicity, blood dyscrasias, taste disturbance Do not use in liver or renal disease Itraconazole Formulations 200 mg tablets 3 5 mg/kg/day x 30d Pulse dosing 200 mg po bid x 7d qmo x 3 mo Drug interactions : anticoagulants, digoxin Do not use with cisapride, astemizole Adverse reactions: rash, GI upset, hepatitis 5

6 Tinea Capitis Treatment Suspect Microsporum? Fluoresces with Wood s lamp History/ contact with animal Treat with griseofulvin Otherwise terbinafine or griseofulvin No need for pretreatment labs Kerion Severe inflammatory reaction to tinea infection Microsporum canis > trichophyton tonsurans Culture may be negative Treat with griseofulvin mg/kg/day and oral corticosteroid Prednisolone 1 2mg/kg/day x 2 weeks 6

7 Tinea Versicolor Hyper or hypopigmented superficial scaling patches on upper trunk, arms Malassezia fufur KOH Spaghetti and meatballs Lipophilic Not cultured Tinea Versicolor Treatment Selenium sulfide, zinc pyrithione Topical antifungals (azoles, allylamines) Oral ketoconazole 400mg x 1, repeat in one week Fluconazole, itraconazole Not oral terbinifine Majocchi s Granuloma Fungal folliculitis Due to topical application of corticosteroid on tinea corporis 7

8 Tinea Corporis Cause Trichophyton rubrum Epidermophyton floccosum T. mentagrophytes (groin/ feet/ nails) KOH > Culture Fungistatic azoles Clotrimazole/ miconazole Fungicidal Terbinifine/ butenafine Head Lice Pediculus humanus capitis Obligate ectoparisite of humans Die within 2 3 days Viable eggs within 6 mm (1/4 inch) of scalp Nymph to adult: 7 days Female lays up to 8 nits/ day Head Lice 6 to 12 million infestations occur each year in US among children 3 to 11 years of age Girls > Boys White > African American Itching can take 4 6 weeks from time of first exposure 8

9 Head Lice Treatment OTC Pyrethrins with piperonyl butoxide (Rid) Permethrin lotion 1% (Nix) By Rx Malathion lotion 0.5% (Ovide) Benzyl alcohol lotion 5% (Ulefsia) Ivermectin lotion 0.5% (Sklice) Lindane shampoo 1% Hints for Head Lice Treat and retreat No treatment completely ovicidal Consider treating whole family Launder bedding, hats etc. Lice and eggs are killed by exposure for 5 minutes to temperatures greater than 53.5 C (128.3 F) Alternately, seal in plastic bag for 2 weeks or dry clean Head lice do not survive long if they fall off a person and cannot feed. You don't need to spend a lot of time or money on housecleaning activities. The End azaenglein@hmc.psu.edu