A comparative study of bacterial and parasitic intestinal infections in India.

BACKGROUND: Infectious diarrhea causes a major health problem in developing countries with significant morbidity and mortality. Very often, rehydration therapy alone does not suffice, mandating the use of antimicrobial agents. However, rapidly decreasing antimicrobial susceptibility is complicating the matters.

MATERIALS AND METHODS: The study aimed to determine the prevalent bacterial and parasitic agents of diarrhea in India. A cross-sectional study was done at Maulana Azad Medical College and associated Lok Nayak Hospital, New Delhi, during 2012-14. Stool samples were received from patients of all age groups and processed for bacteriological and parasitological identification by microscopy, bacterial culture, biochemical identification, serotyping and antimicrobial susceptibility tests. The study also aimed to identify the recent papers (after year 2000) reporting aetiology of infectious diarrhea in India involving the general population as a whole and compare them with present findings.

RESULTS: Out of 6527 samples, 581 (8.90%) were positive for bacterial pathogens. A total of 280 samples (of 3823 under-five year children) were positive for diarrheagenic Escherichia coli. Other organisms like Vibrio cholera were found in 159 (2.44%) cases, Shigella spp. in 126 (1.93%), Salmonella Typhi in 7 (0.11%), Salmonella Typhimurium in 6 (0.10%), Aeromonas hydrophila in 3 (0.05%) cases. Levels of resistance to nalidixic acid, amoxicillin and ciprofloxacin were alarmingly high. Third generation cephalosporins were seen to be moderately active except against E. coli. Parasites were identified in 312 (4.78%) cases. Giardia intestinalis, Ascaris lumbricoides and Entamoeba histolytica were identified in 2.27%, 1.15% and 0.64% cases respectively.

CONCLUSION: Analysis of recent nationwide studies revealed V. cholerae was the most common bacterial/parasitic agent of diarrhea across all populations, being followed by diarrheagenic E. coli and Giardia intestinalis. Periodic laboratory monitoring of antimicrobial susceptibility pattern is essential, as is formulation of effective antibiotic use policy.