Overview of intestinal adaptation and its stimulation

Total parenteral nutrition (TPN) can be life-saving for many patients with short-bowel syndrome (SBS). However, chronic TPN administration is associat ed with nutritional deficiencies, septic complications, high health care co sts, and life-threatening organ failure. In an effort to rehabilitate SBS p atients so they may achieve enteral autonomy, investigators have attempted to stimulate the adaptive response following extensive small-bowel resectio n. intestinal adaptation may include: 1) morphological changes of the resid ual bowel which increase the absorptive surface area; 2) functional changes that increase the absorptive capacity of individual enterocytes and colono cytes; and 3) changes in colonic production and absorption of short-chain f atty acids which improve intestinal vitality and maximize efficiency of ene rgy and fluid absorption. Several peptides, nutrients, cytokines, and other factors promote intestinal adaptation in animals. These "growth" factors m ay predominantly affect one aspect of the adaptive response while having li ttle or no effect on other physiologic or morphologic parameters. In additi on, combined administration of stimulatory agents may be necessary to enhan ce adaptation. Dietary constituents may have profound positive and negative effects on adaptation and must be considered in developing an overall plan for treatment of the SBS patients. Only a few clinical studies have been p erformed to evaluate therapeutic regimens for SBS beyond standard supportiv e care and TPN administration. The combined administration of growth hormon e, glutamine and a modified diet to over 225 adults has been shown to elimi nate or decrease TPN dependence in 80% of patients receiving this therapy. Further study is required to optimize the treatment of humans with intestin al failure and to determine which patients are most likely to benefit from medical therapy. The authors conclude that the intestinal length to body we ight index may be one predictive factor useful far determining which SBS pa tients will benefit: from a trial of phamacologic manipulation before attem pting alternative, potentially more invasive therapies.