Title: Comparison of PCR with stool culture for diagnosis of Asymptomatic Typhoid Carriers in stool samples collected in a tertiary care hospital in East India

Author: Suneel Kumar Ahirwar

 DOI:  https://dx.doi.org/10.18535/jmscr/v6i9.139

Abstract

Background: Typhoid is a disease affecting a large population throughout the world. Besides poverty, low education level and poor hygiene, contact with typhoid patient or a carrier has been identified as major risk factors. Approximately 2–5% of typhoid patients do not clear the infection and progress to carrier state. Stool culture is an important method of diagnosis in such cases. However the yield can be very low and many cases can be missed. Confirmed diagnosis and prompt treatment are essential to control the spread of typhoid.

Material and Methods: The study was conducted in the Department of Microbiology University Hospital, Institute of Medical Sciences, Banaras Hindu University, Varanasi, over a period of one year. Fifty stool samples from suspected asymptomatic carriers with history of clinically and serologically confirmed Typhoid one or more years ago were included in the present study. Stool Culture and PCR was done from the stool samples to confirm presence of S. Typhi carriage and results (yield) were compared.

Results and Discussion: Out of the 50 suspected Typhoid cases, 29 were positive for S.Typhi by PCR (58%) for flagellin gene of S. Typhi, while only 3 (6%) were positive by stool culture. PCR was found to be significantly better than stool culture (p< 0.05)

Conclusion: Stool culture remains a low yielding method which is time consuming and not very fruitful for detection of carriers.PCR for detection of S.Typhi from stool is a good confirmatory tool, especially for tertiary care setups where molecular diagnostic laboratory facilities are readily available.

Keywords: Enteric Fever, Typhoid carrier, S.Typhi, Nested PCR, Flagellin gene.

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Corresponding Author

Suneel Kumar Ahirwar

Assistant Professor, Department of Microbiology, MGM, Medical College, Indore

Ex- Junior Resident IMS, BHU, Varanasi, UP, India