Hepatic lesions of central pericellular fibrosis in morbid obesity, and after jejunoileal bypass.

Histologic findings in liver biopsy specimens obtained from 88 patients before and one and two years after end-to-end jejunoileal bypass are compared. In addition to the expected fatty changes, mild changes of centrilobular, pericellular fibrosis were present in the initial biopsies in 8.6%; a year later they had become apparent in 46%. Portal-central bridging developed in 6.8%, and early micronodular cirrhosis in 3.4%--always in those with central pericellular fibrosis. Electron-microscopic study of pre-bypass liver biopsies from eight addtional patients showed collagen and electron-dense material resembling basement membranes within the spaces of Disse in seven, although only four had light-microscopic evidence of minimal central pericellular fibrosis. The existence of these light- and electron- microscopic changes before jejunoileal bypass suggests that there is a lesion in morbid obesity that may be exacerbated during the first year after operation.