Fecal Calprotectin as a Biomarker Distinguishing Infectious Cause in Acute Intestinal Infections, Comparing Different Age Groups of Children

Background: Fecal calprotectin (FC) measurement has a potential in distinguishing the cause of acute intestinal infections, but its distribution is age dependent. Objectives: With this study we wanted to investigate FC values in different age groups of children with acute intestinal infections. Methods: One hundred and three children with acute intestinal infections were enrolled in this study. Seventy two had viral pathogens, 31 bacterial test subjects were divided into 3 groups: 1 y, 1 - 3 y, 3 - 7 y. Stool samples from test and control subjects (n = 17) were tested for FC with fluorescence enzyme immunoassay. Results: Viral and bacterial pathogen groups had significantly greater FC concentrations, compared to healthy controls. Overall, bacterial pathogen group presented with greater FC values, compared to viral pathogen group (1299.0 mg/kg vs 297.0 mg/kg, P = 0.002). The cut-off value for acute viral intestinal infections was > 70.0 mg/kg (78.2% sensitivity and 100% specificity), bacterial intestinal infections: > 201.0 mg/kg (88% sensitivity and 100% specificity). There was no difference in FC concentration between bacterial and viral pathogen groups in children under one-year-old (391.0 mg/kg vs 399.5 mg/kg, P = 0.945). Differences were significant comparing bacterial and viral pathogen groups of children from 1 to 3 (316.0 mg/kg vs 1799.75 mg/kg, P = 0.001) and from 3 to 7 years old (99.0 mg/kg vs1299.0 mg/kg, P = 0.04). Conclusions: FC is a valuable biomarker for distinguishing bacterial and viral pathogens, except for children under one-year-old.