The patient had cutaneous larva migrans, often caused by Ancylostoma braziliense. (Cutaneous larva migrans. UpToDate Sept. 8, 2004, www.utdol.com/utd/content/topic.do?topicKey=parasite/5637.) Diagnosis of this disease is usually made clinically. A history of travel to an endemic area aids in the diagnosis. This is one of the more common rashes associated with tropical and subtropical areas. In North America, this rash is seen in travelers who are returning from the Caribbean, Central and South America, the southeastern United States, and to a lesser extent Africa and Asia. (Arch Dermatol 1993;129:588.)
Cutaneous larva migrans is caused by infection of the larvae stage of the dog or cat hookworm. (J Emerg Med 2004;26:347.) It is transmitted when a human comes in contact with shaded ground in warmer climates that has been contaminated with dog or cat feces. A lesion occurs where there has been ground contact with the skin, most commonly the feet and buttocks. (Cutaneous larva migrans. EMedicine Aug. 11, 2004; www.emedicine.com/derm/topic91.htm.)
The disease in humans is often self-limited because the larvae will burrow under the skin for approximately eight weeks, causing a localized immune reaction that results in itching and redness. (Am J Med 2005;118:604.) Humans are accidental dead-end hosts for this parasite, and the larvae will usually die, although persistent cases of up to two years have been reported in the literature. (South Med J 1996;89:609.)
The rash typically appears within one week of contact, but can take as long as several weeks to appear, as it did in this patient. (Arch Dermatol 1993;129:588.) The lesions are very pruritic, thin, serpiginous, raised red or brown lesions 2-3 mm wide. The rash will extend with larvae migration at the rate of several millimeters a day. (Revista do Instituto de Medicina Tropical de Sao Paulo 2003;45:167)
Systemic symptoms of cutaneous larva migrans are rare, but have been reported. Pulmonary manifestations of this disease occur when there is hematogenous spread of the larvae. A dry cough indicates lung disease, and a peripheral blood smear may demonstrate eosinophilia. A chest x-ray may show infiltrates, and diagnosis of lung involvement is usually made based on the presence of skin lesions. (Cutaneous larva migrans. UpToDate. Sept. 8, 2004, www.utdol.com/utd/content/topic.dotopicKey=parasite/5637.)
Treatment of cutaneous larva migrans includes either topical thiabendazole 15% for five days or systemic treatment with albendazole 400 mg for three days. (Revista do Instituto de Medicina Tropical de Sao Paulo 2003;45:167.) The patient discussed here was treated with albendazole 400 mg daily for three days. On 30-day follow-up, she reported no further rash, and her symptoms had completely resolved.