Role of concentration techniques and methylene blue wet mount for detection of gastroentestinal parasitic infection: a study from tertiary care hospital

Abstract

Background:- Parasitic infections remain major public health issue in the developing countries. Most of the laboratories are unable to detect parasitic infections by using routine methods like wet mount due to their compromised sensitivity and specificity. Therefore, demonstration of parasitic infections of the specimen poses a huge challenge to the clinical microbiologists.Methods:- A prospective study was conducted over the period of 11 months from August 2018 to June 2019. A total of 200 freshly passed stool samples were transported to the Department of Microbiology in sterile containers.Patients with suspicion of parasitic gastrointestinal infection were included in the study. Fecal samples were immediately examined by iodine, normal saline and Methylene blue wet mounts and then processed by saturated salt solution and Zinc sulfate centrifugation methods, then observed again by with iodine, normal saline and methylene blue wet mounts.Results:- A total of 200 stool samples were examined, out of which 64 (32%) samples were positive for gastrointestinal parasites with wet mount. After concentration methods this increased upto 98 (49%). So with different concentration techniques we were able to detect 34 more parasites. These both concentration techniques have the best impact on detection of parasites, but as per our study Zinc sulfate centrifugation method has more diagnostic value to detect gastrointestinal parasites. Conclusion:-There is still a need to use reliable, economical diagnostic method which can accurately detect parasitic infections and control its spread.