Investigation of Giardia intestinalis in Fresh Stool Specimens By Using Microscopy and EIA

• Main Authors: Kerem YAMAN, Ayşegül TAYLAN ÖZKAN, Gülay AKARSU, Cahit BABÜR, Mesut MUNGAN
• Format: Article
• Language: English
• Published: Bilimsel Tip Yayinevi 2014-03-01
• Series: Flora Infeksiyon Hastalıkları ve Klinik Mikrobiyoloji Dergisi
• Subjects: Giardia; Immunoenzyme techniques; Microscopy
• Online Access: http://www.floradergisi.org/getFileContent.aspx?op=REDPDF&file_name=2014-19-01-054-058.pdf

Giardia intestinalis is one of the most common intestinal protozoan parasite, having a worldwide distribution. Its transmission is by fecal-oral route and is directly related to lack of sanitation and personal hygiene. Giardiasis prevalence is reported to range between 2% and 30% in the world and between 1.9% and 37.7% in different regions of Turkey. The most practical and economic method for the diagnosis of giardiasis is the microscopic examination of the fecal samples. On the other hand, this method needs experienced personnel and its sensitivity in single specimen is reported to be low. As an alternative to microscopy, antigen detection methods such as EIA (Enzyme Immunoassay) and DFA (Direct Fluorescent Antibody) tests have been developed. Our aim in this study was to investigate the presence of G. intestinalis in fresh fecal specimens by using both microscopic method and EIA. The fresh fecal samples of one hundred and eighty patients who applied to Turkish National Institute of Public Health, National Parasitology Reference Laboratory were included in this study. Initially, the samples were examined by microscopy both with native/lugol method and after formol-etyl acetate sedimentation method. The fresh samples separated for EIA were studied according to the manual of the commercial kit and the results were compared. According to the microscopic examination results of 180 fecal specimens examined, while seven samples were positive for G. intestinalis, 22 samples were found to be positive for other protozoa consisting Blastocytis hominis (n= 17), Entamoeba histolytica/ dispar (n= 4) and Entamoeba coli (n= 1). EIA examination revealed that nine of the samples, including the ones detected by microscopy, contained antigens of G. intestinalis. EIA in giardiasis diagnosis is a reasonable choice since it does not require experienced personnel, many samples could be tested simultaneously and it has a high sensitivity and specificity. However, in order not to miss the diagnosis of other possible intestinal parasites, it should be done together with microscopic examination.