EVALUATION OF A COMMERCIALLY AVAILABLE ELISA ASSAY FOR DETECTION OF GIARDIA-LAMBLIA IN FECAL SPECIMENS

A total of 417 fecal samples preserved in 10% buffered formalin and PV A were submitted to a commercial microbiology laboratory only for the defection of Giardia lamblia. Results from fecal specimens collected f rom 411 patients with gastrointestinal symptoms were compared using th e following methods: (a) standard Ova & Parasite (O&P) concentration; (b) Alexon's ProspecT/Giardia enzyme-linked immunosorbent assay (ELISA ) test, and (c) Meridian's Direct Fluorescent Antibody (DFA) Stain. In the 29 specimens in which G. lamblia was defected, 10 were O&P, DFA a nd ELISA positive, 17 were only ELISA positive and two were only Ova & Parasite and Direct Fluorescent Antibody positive. Of the 29 positive specimens, 22 were confirmed as true positives. The ELISA sensitivity was 91% and the specificity was 98%. The expense associated with thes e methods to defect the presence of Giardia is $11.00, $8.95, and $12. 80, respectively. In symptomatic patients, the PuospecT/Giardia ELISA is a cost-effective, rapid, and sensitive method for detecting the pre sence of G. lamblia in fecal specimens.