Chronic strongyloidiasis in Tasmanian veterans--clinical diagnosis by the use of a screening index.

Chronic infection with Strongyloides stercoralis presents a diagnostic problem because of the low recovery of the organism from stools and the insensitivity of current serological tests. Of 150 former Far East POWs, 26 (17%) had S. stercoralis in stools. The clinical features in 18 stool-positive patients were compared to those in 24 stool-negative patients and showed that strongyloidiasis was associated with a higher frequency of alteration in bowel habit, upper abdominal discomfort, rash and eosinophilia. On the basis of these features, a screening index was devised which largely separated stool-positive and stool-negative patients and led to helpful therapy in three of four patients with compatible symptoms who lacked a definitive diagnosis. Treatment with thiabendazole appeared to be superior to treatment with mebendazole.