Low yield of bacterial stool culture in children with nosocomial diarrhea

Objective. To determine whether bacterial stool cultures (BSC) are useful in initial evaluation of children with symptoms of nosocomial diarrhea. To answer this question we performed a retrospective record review to determine the yield of BSC in children who developed diarrhea after the third hospital day (HD-3). Methods. The hospital computer record keeping system was utilized to compile the result of BSC collected from children and adolescents ages 0 to 20 years between January 1, 1988, and October 31, 1996, All specimens were analyzed for Salmonella, Shigella, Yersinia and Campylobacter, We reviewed hospital charts of all children who developed a positive BSC beyond HD-3 to determine the time of onset of diarrhea and clinical circumstances. Results. A total of 11 516 BSCs were submitted from 9262 children during the 8 1/2-year period. Five hundred sixty-eight (6.6%) of 9262 children had at least 1 positive BSC. Two thousand five hundred seventy-two children had the first BSC submitted after HD-3 and 13 (0.5%) of these children had a positive result. Chart review of these 13 children demonstrated that 6 had onset of diarrhea during the first 3 hospital days. Therefore only 7 children met our criteria for having nosocomially acquired diarrhea caused by a bacterial pathogen. Children whose first BSC was submitted after HD-3 accounted for 3767 (46%) of the total 8126 inpatient BSCs and in excess of $21 000 annually in patient billing charges. Conclusion. In the absence of a known exposure the isolation of a bacterial pathogen from the stool of children with onset of diarrhea beyond HD-3 is a rare event. Under most circumstances BSC should not be part of the initial evaluation of children with symptoms of nosocomial diarrhea.