Fecal alpha1-antitrypsin concentrations as a measure of enteric protein loss after modified fontan operations.

BACKGROUND: Little is known about the enteric protein loss in patients after a modified Fontan operation before the appearance of overt symptoms or signs of protein-losing enteropathy (PLE). The authors examined the possibility of using fecal alpha1-antitrypsin concentration measurements for the early detection of postoperative PLE and in longer term postoperative monitoring of these patients.

METHODS: The authors compared fecal alpha1-antitrypsin concentrations in stool samples from 12 children 12.0 to 43.7 months after modified Fontan operations with those of 12 age-matched control subjects and examined the relationship between the alpha1-antitrypsin levels and time since operation. The authors also compared fecal alpha1-antitrypsin concentrations of stools from the same patients obtained at two different time points after surgery with intervals between samples ranging from 14.7 to 19.8 months.

RESULTS: No significant differences in serum total protein and albumin levels were observed between patients after the modified Fontan operation and control subjects. The fecal concentrations of alpha1-antitrypsin in patients after the Fontan operation were significantly (P < 0.01) higher than those in control subjects. There was no significant correlation between fecal alpha1-antitrypsin concentrations and time elapsed after the Fontan operation. The fecal alpha1-antitrypsin concentration increased significantly (P < 0.01) over periods of 14.7 to 19.8 months after the first measurement.

CONCLUSION: The results show that enteric protein loss begins before the appearance of hypoproteinemia in patients after a modified Fontan operation, and that the measurement of fecal alpha1-antitrypsin concentrations in random stool samples is useful as an early indicator. To watch for the development of PLE after Fontan operation, it may be important to perform longitudinal follow-up examinations of enteric protein loss by measuring fecal alpha1-antitrypsin concentrations early in the postoperative period.