Does liver appearance predict histopathologic findings: prospective analysis of routine liver biopsies during bariatric surgery.

Background: Nonalcoholic fatty liver disease is associated with morbid obesity. Liver biopsy is the reference standard for the diagnosis of nonalcoholic fatty liver disease. It is unclear whether the macroscopic liver appearance correlates with the histopathologic findings. Our objective was to determine the relationship between the intraoperative liver appearance and the histopathologic findings during laparoscopic bariatric surgery at a tertiary medical center.

Methods: Data were prospectively collected from 108 consecutive patients undergoing laparoscopic bariatric surgery with routine intraoperative liver biopsy. An intraoperative liver visual score was recorded according to the size, tan-speckling, and contour. The liver histologic findings were categorized into 3 groups: (1) normal; (2) bland steatosis; and (3) nonalcoholic steatohepatitis (NASH). The liver visual score was compared with the liver histologic findings. A recorded video of the liver was regraded at a later date to determine observer agreement.

Results: The prevalence of NASH was 23% (n = 25). Of the 108 patients, 48% with NASH had normal-appearing livers and accounted for 24% (n = 12) of the 50 normal-appearing livers. A similar proportion of NASH cases was found in all 3 visual categories. Furthermore, no relationship was found between the number of abnormal visual cues and the liver histologic findings (P = .23). No complications were directly attributable to liver biopsy. The kappa values for intraobserver and interobserver agreement ranged from fair to almost perfect.

Conclusion: NASH is common in the morbidly obese population. There does not appear to be a relationship between liver appearance and the histopathologic findings. Intraoperative liver biopsy is a safe and accurate method of diagnosing liver disease and should be considered in all morbidly obese patients undergoing abdominal surgery.