Parasitic Skin Infections Flashcards
What are the parasitic skin infections?
Scabies
Crusted scabies
Lice infestation / pediculosis
Cutaneous larva migrans
Cutaneous leishmaniasis
Papular urticaria following insect bites
What is scabies?
Caused by mite Sarcoptes scabiei var hominis
Spread by skin to skin contact and fomites
Female burrows into corneum, lays eggs
Common in children < 5 years, elderly , and bedridden patients
Burrows are pathognomonic, in web spaces
Nocturnal pruritis
Rx is scabicides (benzyl benzoate)
What is Norwegian scabies?
Severe scabies
Occurring in immunocompromised, malnutrition, mental disease
Scaly crusted lesions on hands and feet
Highly infective
Rx Ivermectin and scabicides
Complications are AGN
What is cutaneous larva migrans?
Cutaneous infestation by nematodes (ancyclostoma)
Following percutaneous penetration and epidermal migration of larva
Induce an eosinophilic inflammatory reaction
Seroinginous, linear, tunnel like lesions on exposed body sites, commonly feet
Rx thiabendazole 50mg/kg/day for 5 days
What is cutaneous leishmaniasis?
Caused by leishmania donovani
Transmitted by Sandfly vector phlebotomus
Initial non tender non pruritic pupule
Enlarged slowly to a nodule
Crusting
Shallow ulcer with raised indurated border (volcano sign)
Can have satellite lesions
Untreated , heals with a depressed scar
Rx cryotherapy and sodium stibogluconate
What are the types of pediculosis?
Pediculosis capitis
- pediculosis humanus var capitis
Pediculosis corporis
- pediculosis humanus var corporis
Is a vector for epidemic typhus
Pediculosis pubis
- pthirus pubis
What is pediculosis pubis?
Caused by crab lice (pthirus pubis)
Transmitted by sexual contact/ sharing toiletries and linen
Common in young adult hairy males
Nocturnal itching of public area
Lice and nits in hairy areas have to be seen
Papules and excoriations
Secondary bacterial infection
Eczematization and pigmentation
Rx 1% permethrin to all hairy areas for 12 hours, repeat in a week
Treat contacts
Change or launder linen
What is papular urticaria from insect bites?
Hypersensitivity urticaria
Excoriated
Bullous or secondary infection
Resolve in weeks
EC topical steroids and antibiotics
What is pediculosis capitis?
Transmitted by head to head contact, sharing amenities
Nits are cemented to hair
Common in young children, long haired women and unhygienic
