Faecal calprotectin as an inflammatory biomarker to distinguish between bacterial and viral causes of childhood diarrhoea in Indian settings.

OBJECTIVES: The purpose of this study was to determine the value of faecal calprotectin (f-CP) in distinguishing between bacterial and viral aetiologies of infective diarrhoea in children attending a tertiary care hospital in Central India. METHODS: Stool samples from children aged 3 months to 10 years who had acute or persistent diarrhoea were processed for microscopy, bacterial culture, and viral antigen detection (Rotavirus and Norovirus). The remaining samples, as well as stool samples from 20 healthy controls, were tested for f-CP using the enzyme linked immunosorbent assay. RESULTS: Among 48 patients, 21 (43.7%) had bacterial diarrhoea, 14 (29.2%) had viral diarrhoea, and 13 (27.1%) had an unidentified aetiology. The median f-CP values were significantly (p â€‹= â€‹0.004) higher in children with bacterial diarrhoea (75.2 â€‹µg/g; IQR-18.75-239.15) than in children with viral diarrhoea (75.2 â€‹µg/g; IQR-123.5-1987.5). Bacterial aetiology could be reliably predicted at the optimum f-CP concentrations of >541 â€‹µg/g and >238.4 â€‹µg/g in children aged 1 and 1-4 years, with an area under the curve of 0.767 and 0.867, respectively, using receiver-operator characteristic analysis. CONCLUSIONS: Faecal calprotectin could reliably distinguish between bacterial and viral aetiologies of diarrhoea in children aged up to four years, but at relatively higher age-specified cut off values.