A comparative study of four methods for detecting antibody in asymptomatic giardiasis.

Four immunological methods for diagnosis of giardiasis comprising complement fixation (CF) test, indirect hemagglutination (IHA) test, enzyme-linked immuno sorbent assay (ELISA) and lectin immuno test (LIT) were studied. Fifty sera from asymptomatic giardiasis patients, 40 from patients with other diseases and 50 from healthy controls were evaluated. The seropositive rates in asymptomatic giardiasis were 36% for CF, 58% for LIT, 30% for IHA and 72% for ELISA. The seropositive rates in patients with other diseases were 22.5% for CF, 52.5% for LIT, 12.5% for IHA and 67.5% for ELISA. The results suggest that the test of choice for giardiasis was CF with 88% specificity, nevertheless this test showed low sensitivity (36%). Other two tests, ELISA and LIT were more sensitive than CF with percent sensitivity of 72 and 58 respectively, but these two tests had severe disadvantages in being less specific with percentage specificity of 48 and 60 respectively.

Cryptosporidiosis in Siriraj Hospital, Bangkok, Thailand.

During January to July 1986, 1,500 fecal specimens from out and in-patients attending Siriraj Hospital, Bangkok were examined for Cryptosporidium oocysts by modified acid fast technique. Eight were found to be positive. The prevalence of cryptosporidiosis was 3.7% in children with acute diarrhoea. Medical records of the patients showed that the main clinical presentation was acute diarrhoea with fever for one to 7 days duration. Stool examinations and cultures revealed no white blood cells or parasites or other enteropathogenic bacteria. All recovered within two weeks. The study suggest that Cryptosporidium is a relatively common nonviral cause of acute diarrhoea in young children and routine laboratory study to detect Cryptosporidium may be justified.