Protein-losing enteropathy in the human and experimental rat blind-loop syndrome.

Protein-losing enteropathy in 2 human subjects with small intestine bacterial overgrowth is reported. Partial improvement in 1 and complete normalization in the 2nd, during long-term antibiotic therapy, demonstrate for the first time antibiotic reversibility of protein-losing enteropathy in the human blind-loop syndrome. Studies in rats with experimental jejunal blind loops revealed depressed serum protein levels and excessive fecal excretion of intravenously administered 51Cr as compared with nonoperated and surgical controls. Comparison of protein loss of rats with blind loops present for varying lengths of time and paired comparison of rats tested for protein loss at two different times revealed a relatively stable degree of protein loss once it was manifest. Reversal of protein loss with antibiotic therapy was accomplished in only a small percentage of rats, and in those only after prolonged therapy. Surgical extirpation of the blind loop from rats with protein-losing enteropathy consistently corrected the protein loss, although this correction was delayed up to 9 wk from the time of corrective surgery. These studies demonstrate (a) significant protein loss as one etiologic factor for protein metabolic disturbances in the human and experimental rat blind-loop syndrome, (b) the occurrence of intestinal protein loss as a manifestation of functionally significant mucosal injury in the contaminated nonstagnant small bowel as well as the stagnant part of the small intestine affected by bacterial overgrowth, and (c) the difficulty of reversing functionally significant mucosal injury in the blind-loop syndrome once it has been manifest.