Fecal S100A12 in Healthy Infants and Children

Background and Aims. Fecal S100A12 is shown to be a useful noninvasive marker of gut inflammation. However, the studies to date have not characterised the patterns of expression in healthy young children. This study aimed to determine S100A12 levels in infants and children without symptoms of underlying gut disease. Methods. Stool samples were collected from healthy infants (<12 months) and children without gastrointestinal symptoms. Faecal S100A12 was measured by immunoassay. Results. Fifty-six children were recruited. Serial samples were obtained from seven term infants over the first 6 months of life. Single samples were obtained from 49 healthy children ranging from 0.16 to 13.8 years of age. Median S100A12 levels were 0.5 mg/kg (ranging from 0.39 to 25) in the healthy children, with high values (>10 mg/kg) in five infants only. There was no variation between gender. Median S100A12 levels in healthy infants remained below the established normal cut-off from birth to six months of age. Conclusion. S100A12 levels in well infants and children are almost exclusively lower than the standard cut-off. Transiently higher levels may be seen in early infancy. An elevated level of S100A12 in children older than 12 months of age is likely to represent organic gut disease.