Display Settings:

Format

Send to:

Choose Destination
See comment in PubMed Commons below
J Clin Microbiol. 2011 Mar;49(3):975-83. doi: 10.1128/JCM.01392-10. Epub 2010 Dec 22.

Development and evaluation of a real-time PCR assay for detection and quantification of blastocystis parasites in human stool samples: prospective study of patients with hematological malignancies.

Author information

  • 1Clermont Université, JE 2526, Evolution des bactéries pathogènes et susceptibilité de l'hôte, BP 10448, F-63000 Clermont-Ferrand, France.

Abstract

Blastocystis anaerobic parasites are widespread worldwide in the digestive tract of many animal species, including humans. Epidemiological Blastocystis studies are often limited by the poor sensitivity of standard parasitological assays for its detection. This report presents a highly sensitive real-time quantitative PCR (qPCR) assay developed to detect Blastocystis parasites in stool samples. The assay targets a partial sequence of the Blastocystis small ribosomal subunit (SSU) rRNA gene, allowing subtyping (ST) of Blastocystis isolates by direct sequencing of qPCR products. This qPCR method was assessed in a prospective study of 186 patients belonging to two cohorts--a group of 94 immunocompromised patients presenting hematological malignancies and a control group of 92 nonimmunocompromised patients. Direct-light microscopy and xenic in vitro stool culture analysis showed only 29% and 52% sensitivity, respectively, compared to our qPCR assay. Of the 27 (14.5%) Blastocystis-positive patients, 8 (4%) experienced digestive symptoms. No correlation was found between symptomatic patients and immune status, parasite load, or parasite subtypes, although subtyping of all isolates revealed a high (63.0%) prevalence of ST4. Two unexpected avian subtypes were found, i.e., ST6 and ST7, which are frequently isolated in Asia but rarely present in Western countries. In conclusion, this qPCR proved by far the most sensitive of the tested methods and allowed subtype determination by direct sequencing of qPCR products. New diagnostic tools such as the qPCR are essential for evaluating the clinical relevance of Blastocystis subtypes and their role in acute or chronic digestive disorders.

PMID:
21177897
[PubMed - indexed for MEDLINE]
PMCID:
PMC3067686
Free PMC Article

Images from this publication.See all images (3)Free text

Fig. 1.
Fig. 2.
Fig. 3.
PubMed Commons home

PubMed Commons

0 comments
How to join PubMed Commons

    Supplemental Content

    Full text links

    Icon for HighWire Icon for PubMed Central
    Loading ...
    Write to the Help Desk