Photo Rounds Friday Archive

Rash on feet and buttocks

Post Date: 12/25/2009

FIGURE 1	FIGURE 2
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A mother brought her 18-month-old son to the doctor's office for an itchy rash on his feet and buttocks. The physician made a presumptive diagnosis of tinea corporis, but topical clotrimazole cream failed after a 2-week trial. The child had been unable to sleep at night due to the intense itching and was losing weight secondary to his poor appetite. He was taken to an urgent care clinic where the physician learned that the family had returned from a trip to the Caribbean prior to the first visit to the physician. The child had played on beaches that were frequented by local dogs.

What's your diagnosis?

The physician diagnosed cutaneous larva migrans (CLM). CLM is typically caused by dog and cat hookworms (ie, Ancylostoma braziliense, Ancylostoma caninum). Eggs are passed in cat or dog feces. The larvae are hatched in moist, warm sand/soil. The infective stage larvae penetrate the skin and start to crawl under the skin, looking for access to the intestines. In humans, they never make it beyond the skin.

This patient acquired the disease abroad, but it does occur in the United States—predominantly in Florida and the Gulf Coast. Children are more frequently affected.

Oral thiabendazole is the only FDA-approved medication for CLM. It can also be compounded to form a topical cream (15%) from 500 mg tablets in a water-soluble base. The cream is a good choice for children who can’t swallow the tablets. Oral ivermectin (Stromectol) has been well studied and is considered the drug of choice by many. A single dose of 0.2 mg/kg is recommended. High cure rates have been reported with no adverse events. In this case, the child was treated successfully with topical thiabendazole.

Photos and text for Photo Rounds Friday courtesy of Richard P. Usatine, MD. This case was adapted from: Keehbaugh, J. Cutaneous larva migrans. In: Usatine R, Smith M, Mayeaux EJ, Chumley H, Tysinger J, eds. The Color Atlas of Family Medicine. New York, NY: McGraw-Hill; 2009:581-583.

To learn more about The Color Atlas of Family Medicine, see:
* http://www.amazon.com/Color-Atlas-Family-Medicine/dp/0071474641
* http://www.mhprofessional.com/product.php?isbn=0071474641