Clinical evaluation of fecal lactoferrin and α 1-antitrypsin in pediatric gastrointestinal infections

To investigate the pathophysiology of acute gastrointestinal infections in the pediatric field, daily fecal excretion of lactoferrin (Lf) and α 1-antitrypsin (AT) was examined in pediatric patients with acute viral gastroenteritis syndrome (AVGS) ( n = 17) or bacterial enterocolitis ( n = 10) and in control children ( n = 27). The pathogenic bacteria were Salmonella species ( n = 4), Campylobacter jejuni ( n = 3), pathogenic Escherichia coli ( n = 2) and Clostridiumdifficile ( n = 1). A greater daily fecal excretion was found in the AVGS and bacterial enterocolitis groups when compared with the control group. In addition, fecal AT excretion was significantly greater in the bacterial infection group than in the AVGS and control groups. The latter two groups showed no significant difference. The AT clearance (ATC) was calculated based on the fecal and serum AT levels. ATC was greatest in the bacterial infection group. In the AVGS group, ATC was also greater than in the control group but not statistically significant. Generally, the fecal AT content is thought to reflect protein loss, while the fecal Lf content seems to reflect the inflammatory response. Fecal Lf content differed between the AVGS and bacterial enterocolitis groups. The difference in the Lf level may come from differences in the extent of neutrophil infiltration into the bowel. We conclude that simultaneous assay of Lf and AT is useful for evaluation of the pathophysiology of gastrointestinal infection.