Clinical characteristics and predictors of positive stool culture in adult patients with acute gastroenteritis.

OBJECTIVE To identify the presenting features and spectrum of pathogens in adult patients with acute diarrhoea and to determine the predictors of stool culture positivity. METHODS A descriptive study was conducted in a tertiary care hospital from April 1, 2005 to March 31, 2006. Medical records of all consecutive adult patients with history of acute diarrhoea were reviewed between June 2006 to December 2006 for clinical characteristics and laboratory investigations. RESULTS A total of 454 patients were admitted from April 1, 2005 to March 31, 2006. Stool cultures were performed in 233 (50%) patients, 96 (42%) had positive results. Patients with positive stool culture compared to a negative Culture were found to have a younger mean age (43 vs. 53), greater number of unformed stools (16 vs. 11) and low serum bicarbonate level (16 vs. 20). Vibrio cholerae (86%) was found to be the most prevalent organism followed by Salmonella spp (6%), Campylobacter spp (5.2%), Shigella spp (2%). Ciprofloxacin was given to 97% patients along with fluid administration, and 78% were found to be resistant to quinolones. Most patients recovered before the finalized stool culture results. CONCLUSION Careful selection of the patients based on their clinical presentation and initial laboratory work up can help to decide ordering of stool culture in adults with diarrhoea. Fluid resuscitation remains the main stay of treatment.