Select Helminth Infections

Ancylostomabraziliense

Vector: penetration of skin by larvae

Erythematous, serpiginous “tract” with ↑↑ pruritus; typically occurs after walking barefoot in area contaminated by animal feces (eggs in animal feces → passed to soil and larvae hatch)

Topical thiabendazole, oral ivermectin or albendazole

Loiasis
Calabar swelling

Loa loa

Vector:deer or mango fly (Chrysops, family Tabanidae)

Calabar swelling: subcutaneous edema containing female worm, ± conjunctivitis (adult worm migrating across conjunctiva)

Diethylcarbamazine

Filariasis
Elephantiasis

Wuchereria bancrofti

Vector: mosquitoes (Aedes, Culex)

Acute: recurrent lymphangitis and fever
Chronic: lymphedema, elephantiasis (most commonly involving genitalia and lower leg)

Diethylcarbamazine

Dracunculiasis
Guinea worm disease

Dracunculus medinensis

Vector: infected water crustaceans (Cyclops)

Ingestion of infected water fleas → wheezing, pruritus, urticaria → worm migrates from GI tract to skin (usually lower leg) where bulla forms and later erupts to release worm and larvae

Thiabendazole or niridazole

Onchocerciasis
River blindness

Varying presentations including subcutaneous nodules containing worms, dermatitis, depigmentation on lower legs, and vision loss

Mazzotti reaction: severe reaction with urticaria and systemic signs associated with diethylcarbamazine

Ivermectin or diethylcarbamazine

Schistosomiasis
(visceral)
Bilharziasis

Schistosoma mansoni,
S. haematobium
S. japonicum

Vector: water infected with worm eggs/feces

Acute (Katayama fever): severe urticarial eruption which serum sickness-like symptoms (fever, headache, myalgias, arthralgias)

Chronic: involvement of liver, lungs, bladder, or CNS, ± painless verrucous nodules at sites of ectopic deposition of eggs

Praziquantel

Cercarial dermatitis Swimmer’s itch

Trichobilharzia spp. (Avian schistosome)

Vector: water infected with worm eggs/feces

Larvae from infected waters penetrate skin → larvae die immediately but cause short-term immune reaction with pruritic erythematous macules and papules in exposed areas (the species causing this eruption is less pathogenic than in schistosomiasis and cannot enter bloodstream or deeper tissue)

Oral antihistamine and topical antipruritics

		Of note, seabather’s eruption on covered areas (due to larvae of thimble jellyfish)

Strongyloides
Racing larva Larva currens

Strongyloides stercoralis

Vector: direct contact with soil contaminated with larvae

Initially see rapidly moving form of larva migrans (5–10 cm/h) → migrates to lungs, ascends, and then is swallowed entering GI tract → larvae excreted via feces, but can cause autoinfection by penetrating perianal skin → intensely pruritic perianal rash with radiating urticarial bands

Albendazole, thiabendazole, or ivermectin