Detection of Enterocytozoon bieneusi (Microsporidia) by polymerase chain reaction (PCR) using species-specific primer in stool samples of HIV patients.
OBJECTIVE
Microsporidia are obligate intracellular parasites causing infections predominantly in immunocompromised patients. Enterocytozoon bieneusi is the most important microsporidian causing chronic diarrhoea in AIDS patients. The current method used for diagnosing the microsporidia spores is based on light microscopy using stained smears, which do not differentiate spores at species level. The present study was undertaken to detect microsporidia and confirm at species level (E. bieneusi) by PCR from stool samples of HIV positive patients.


METHODS
During September 2002 to April 2003, stool samples from 153 HIV-positive patients (with chronic diarrhoea n = 105; without diarrhoea n=48) were collected and examined microscopically for microsporidia spores using modified Weber's chromotrope stain. Stool samples were subjected to PCR assay using species-specific primer EBIEFI/EBIER1, which amplifies small subunit ribosomal RNA (SSU rRNA) of this microsporidian


RESULTS
A total of 10 HIV positive patients with chronic diarrhoea were positive for microsporidia by microscopic analysis and confirmed as Enterocytozoon bieneusi by PCR. No false positive results were observed. A diagnostic DNA fragment of 607 bp of the unique SSU rRNA was amplified from all samples infected with E. bieneusi.


CONCLUSIONS
The study revealed that polymerase chain reaction is a useful tool for accurate species identification of microsporidia in stool samples, which serves the benefit of treatment to the patients.
Kumar
S Satheesh
SS
Department of Microbiology, Dr ALM Post Graduate Institute of Basic Medical Sciences, University of Madras, Chennai 600 013, India. sowanand@hotmail.com
Ananthan
S
S
Joyee
A G
AG
D001483:Base Sequence; D017931:DNA Primers; D003967:Diarrhea / Q000150:complications / Q000469:parasitology; D021862:Enterocytozoon / Q000235:genetics / Q000302:isolation & purification*; D005243:Feces / Q000469:parasitology*; D015658:HIV Infections / Q000150:complications / Q000469:parasitology*; D006801:Humans; D016133:Polymerase Chain Reaction / Q000379:methods*; D016053:RNA, Protozoan / Q000302:isolation & purification
D017931:DNA Primers; D016053:RNA, Protozoan