(BMJ)—A 26-yo woman presented w/ an itchy rash on her foot that started as a small blister 6 days after returning from Barbados. It had not responded to topical steroids or antifungals. Exam: red, serpiginous rash on dorsum of right foot. What is the dx?
Epidermal dermatophytosis
Erythema migrans
Cutaneous larva migrans
Migratory myiasis
Larva currens
You are correct. Cutaneous larva migrans is the result of a zoonotic infxn from nematode parasites (such as Ancylostoma braziliense) of the hookworm family, which do not use humans as the definitive host. The parasite lacks collagenase to penetrate deeper tissues in humans, resulting in the “creeping” pattern. This pt was treated w/ a single dose of ivermectin, an anthelmintic. On f/u 10 days later, the rash had resolved.

BMJ 2017;359:j4343