Genotyping of Giardia lamblia isolates from human in southern Iran.

Giardia lamblia cysts isolated from human faeces in South of Iran were analyzed with PCR-restriction fragment length polymorphism (RFLP) assay, based on the detection of glutamate dehydrogenase (gdh) genes. Among 205 faecal samples from microscopically diagnosed giardiasis patients, the gdh gene was amplified from 172 cases with a semi nested PCR assay and typed by RFLP analysis. Of the 172 positive samples, 128 (74.41%) were typed as assemblage AII, 30 (17.44%) assemblage BIII, 6 (3.49%) assemblage BIV and in 8 (4.66%) isolates, mixed assemblages AII and BIV were detected. Clinical features were available for 52 successfully typed cases and the possible correlation of Giardia assemblages and clinical symptoms was evaluated. Both assemblages caused similar illness, but assemblage AII was significantly more frequently associated with abdominal pain, nausea and vomiting. Since these isolates, A and B, are of human origin, anthroponotic transmission of Giardia can be suggested for the route of infection in this region.