Objective: The current study was undertaken to assess the frequency of
excessive enteric protein loss and protein-losing enteropathy in the
relatively early period after the Fontan operation. Design: Protein ex
cretion was determined in 26 of 27 consecutive patients who underwent
the Fontan procedure between January and June 1990 at the Mayo Clinic.
Material and Methods: At two testing intervals during the first 4 mon
ths after the Fontan operation, alpha(1) antitrypsin clearance and fec
al alpha(1)-antitrypsin concentration studies were done. Results: All
results were normal for the first postoperative test period (2 to 8 we
eks). For the second study period, all 17 patients tested had normal a
lpha(1)-antitrypsin clearances. One of the 17 patients had an apprecia
bly increased fecal alpha(1)-antitrypsin concentration and transient p
rotein-losing enteropathy. Conclusion: Excessive enteric protein loss
and protein-losing enteropathy are relatively uncommon during the firs
t 4 months after the Fontan operation.