Cutaneous larva migrans

Overview
Cutaneous larva migrans ("CLM") is a skin disease in humans, caused by the larvae of various nematode parasites, the most common of which is Ancylostoma braziliense.

Sometimes referred to as "creeping eruption" or "ground itch", in some parts of the Southern USA this condition is also referred to as "sandworms," as the larvae like to live in sandy soil.

Cause
These parasites are found in dog and cat feces and although they are able to infect the deeper tissues of these animals (through to the lungs and then the intestinal tract), in humans they are only able to penetrate the outer layers of the skin and thus create the typical wormlike burrows visible underneath the skin. The parasites apparently lack the collagenase enzymes required to penetrate through the basement membrane deeper into the skin.

Presentation
The infection causes a red, intense itching eruption. The itching can become very painful and if scratched may allow a secondary bacterial infection to develop.

Treatment
CLM can be treated a number of different ways:


 * Systemic (oral) agents include albendazole (trade name Albenza) and ivermectin (trade name Stromectol).


 * Another agent which can be applied either topically or taken by mouth is thiabendazole (trade name Mintezol), an anti-helminthic. When taken orally, this medication is known to cause nausea.


 * Topical freezing agents, such as ethyl chloride or liquid nitrogen, applied locally can freeze and kill the larvae (but is often a hit-or-miss proposition).