Efficacy of Fecal Calprotectin Combined With Stool Hemoglobin in Differentiating Bacterial Origin in Acute Gastroenteritis.

Abstract

Differentiating bacterial origin in acute gastroenteritis (AGE) is important to improve outcomes. Fecal calprotectin is a sensitive screening tool for gut mucosal inflammation. This study aimed to evaluate the diagnostic efficacy and cutoff level of fecal calprotectin in distinguishing bacterial origin in pediatric AGE. Patients who were diagnosed with AGE at 1 to 18 years between January 2015 and January 2020 were retrospectively analyzed. A polymerase chain reaction test was applied to stool samples to detect viruses and bacteria. The level of fecal calprotectin was determined using an enzyme-linked immunosorbent assay test. Eighty patients were enrolled in this study. The most common viral pathogen was norovirus, and bacterial pathogen was Clostridium perfringens. The median fecal calprotectin level was 686 μg/g (interquartile range [IQR], 140-1192 μg/g) in all patients, 560 μg/g (IQR, 60-669 μg/g) in patients with viral pathogens, and 985 μg/g (IQR, 272-1984 μg/g) in those with bacterial pathogens (P = 0.019). The stool hemoglobin concentration (337.29 vs 84.83 ng/mL, P = 0.016) and C-reactive protein (4.06 vs 0.45 mg/dL, P = 0.082) levels were higher in patients with bacterial pathogens than in those with viral pathogens. For identifying bacterial pathogens, the area under the receiver operating characteristic curve of fecal calprotectin was 0.739 (95% confidence interval, 0.584-0.894); combination with stool hemoglobin improved diagnostic efficacy, and the area under the receiver operating characteristic curve was 0.870. The optimal cutoff values of fecal calprotectin and stool hemoglobin were 815 μg/g and 158 ng/mL, respectively. The combination of stool hemoglobin and fecal calprotectin may be a useful marker for detecting bacterial etiology in pediatric AGE.