Clinical and laboratory predictors of acute bacterial diarrhea

الملخص EN

Objective: diarrhea is one of the most common childhood illnesses worldwide and exerts major financial impact.

The presence of gross blood or an inflammatory response in the stool (leukocytes or lactoferrin) significantly increases the chance for isolation of invasive enteric bacteria.

Improved knowledge of the microbiologic etiology of childhood diarrhea could help clinicians make appropriate diagnostic and therapeutic decisions and diminish the burden of these illnesses.

The aim of this work is to determine the predictive utility of certain clinical and stool parameters in diagnosing bacterial diarrhea. Methods: A prospective one year study was conducted on 142 patients, below 5 years of age, with acute diarrhea, in Babylon Maternity and Children Teaching Hospital (Outpatient and Emergency department) during the months of January to December 2007. Results: The positive stool culture was yield in 64 patients (45.07%).

The isolated pathogens were Escherichia coli in 44 patients ( 68.7%), shigella spp.

in 14 patients (21.6%), and Salmonella spp.

in 6 patients (9.3%).

The best predictive variable for a stool culture positive for a bacterial pathogen was the presence of fecal leucocytes, with a sensitivity of 92%, a specificity of 75%, and positive and negative predictive values of 75% and 92%, respectively, with odd ratio of 36.6.

The next predictive variable was the presence of both fecal leucocytes and fecal blood with a sensitivity of 88%, a specificity of 82%, and positive and negative predictive values of 76% and 91%, respectively, with odd ratio of 36.1.

The best historical factors for predictive accuracies were abrupt onset, fever≤ 38°C, abdominal pain, frequent bowel motions and no vomiting before the onset of diarrhea. Conclusions: Examination of stool for fecal leukocytes and fecal blood is a rapid, reliable, and inexpensive way to be the best method of predicting a positive stool culture, while detecting a blood in the stool only had high specificity with low sensitivity.