When hyperinfection is present, Strongyloides larvae may be found in other fluids, such as surgical drainage fluid and sputum, and the stool may contain filariform and rhabditiform larvae. Treatment Strongyloidiasis must be treated because of the potential for subsequent fatal hyperinfection. Thiabendazole is often associated with unpleasant side effects and is not uniformly successful. Although not approved for the treatment of strongyloidiasis in the United States, albendazole is an effective agent. Serial stool examinations should be obtained in the weeks and months after therapy to confirm eradication of the parasite.
Infection is most common in Asia and is acquired by consuming food that harbors infectious larvae.
Adult worms attach to the proximal small bowel and in most cases do not produce symptoms. The eggs of Trichostrongylus are somewhat larger and have less rounded ends than hookworm eggs. Most human infection with Capillaria is caused by C. philippinensis, which is found primarily in the northern Philippines and Thailand. Humans acquire the infection by eating raw freshwater fish. Symptomatic intestinal capillariasis is marked by diarrhea and abdominal pain.