Diagnosis of Giardia infections by PCR-based methods in children of an endemic area

Autor(es)

David, E. B. ^[1] ; Coradi, S. T. ^[2] ; Oliveira-Sequeira, T. C. G. ^[1] ; Ribolla, P. E. M. ^[1] ; Katagiri, S. ^[1] ; Guimaraes, S. ^[1]

Afiliação do(s) autor(es)

^[1] UNESP Univ Estadual Paulista, Sao Paulo State Univ, Dept Parasitol, Botucatu Biosci Inst, Botucatu, SP - Brazil

^[2] Univ Sagrado Coracao, USC, Dept Biol & Hlth Sci, Bauru, SP - Brazil

• Tipo de documento: Artigo Científico
• Fonte: Journal of Venomous Animals and Toxins including Tropical Diseases; v. 17, n. 2, p. 209-215, 2011.
• Citações Web of Science: 12

Resumo

The present study was designed to estimate the prevalence of Giardia infection in preschool- and school-aged children living in an endemic area. Fecal samples from 573 children were processed by zinc sulfate centrifugal flotation, centrifugal sedimentation (using a commercial device for fecal concentration - TF-Test kit (R)) and polymerase chain reaction (PCR)-based methods. Of the stool samples assessed, 277 (48.3%) were positive for intestinal parasites and/or commensal protozoa. Centrifugal flotation presented the highest diagnostic sensitivity for Giardia infections. The kappa index revealed that both coproparasitological techniques closely agreed on the Giardia diagnosis (86%) versus satisfactory (72%) and poor (35%) concordances for commensal protozoan and helminth infections, respectively. Concerning Giardia molecular diagnosis, from the 71 microscopy-positive samples, specific amplification of gdh and tpi fragments was noted in 68 (95.7%) and 64 (90%) samples, respectively. Amplification of gdh and tpi genes was observed, respectively, in 95.7% and 90% of microscopy-positive Giardia samples. For 144 microscopy-negative samples, gdh and tpi gene amplification products were obtained from 8.3% and 35.9% samples, respectively. The agreement between these genes was about 40%. The centrifuge-flotation based method was the most suitable means of Giardia diagnosis assessed in the present study by combining accuracy and low cost. (AU)

• Processo FAPESP: 06/56151-3 - Prevalência das parasitoses intestinais humanas e de cães e significado zoonótico das infecções por Giardia e Cryptosporidium no Estado de São Paulo
• Beneficiário: Semíramis Guimarães Ferraz Viana
• Linha de fomento: Auxílio à Pesquisa - Regular