Morphological and functional changes of the liver following small intestinal bypass for obesity.

Liver biopsies of 6 patients were obtained at time of jejuno-ileal bypass and compared with liver biopsies obtained at 6, 12, and 18 months after the operation. The extent of fatty changes, cellular infiltration, connective tissue infiltration, and parenchymal cell damage was recorded. In biopsies taken 6 and 12 months postoperatively a considerable increase was observed in steatosis and cell damage, biopsies obtained at 18 months after the operation showing reduction or clearing of fat. Transient increase in periportal cell infiltration was observed, and in one patient a manifest cirrhosis developed, necessitating partial reversal of the shunt. An attempt was made to correlate the histological changes with alterations in standard liver function tests. The tests were of limited value in predicting the histological changes unless the morphological changes were very serious and the liver in a state of insufficiency. The importance of liver biopsies in the follow-up of bypass patients is stressed.