Laboratory findingS WBC 7100/mm3, with 10% PMNS, 63% bands, 19%lymphocytes blood urea nitrogen of 63 mg/dL; and serum creatinine of 2. 1 mg/dL Methylene blue smear of the stool few PMNs and few mononuclear cells. Gram stain: mixed flora Stool culture Salmonella enteritidis The case summarizes the characteristics of the most common bacterial causes of diarrhea• Laboratory findings: WBC 7100/mm3, with 10% PMNs, 63% bands, 19% lymphocytes; blood urea nitrogen of 63 mg/dL; and serum creatinine of 2.1 mg/dL. Methylene blue smear of the stool: few PMNs and few mononuclear cells. Gram stain: mixed flora. Stool culture: Salmonella enteritidis. The case summarizes the characteristics of the most common bacterial causes of diarrhea. 10