Recommendations for the investigation of abnormal hepatic function in asymptomatic workers

Occupational medicine programs use medical surveillance tests to measure physiologic parameters that may be affected by workplace exposures. Surveillance tests can detect early detrimental changes before workers manifest recognizable symptoms. Hepatic function testing is one type of surveillance test used to monitor workers exposed to hepatotoxins. However, a significant proportion of these test reports return showing abnormal hepatic function without a readily apparent etiology. Follow-up investigation of abnormal liver enzyme tests is a commonly encountered problem in occupational medicine clinics. The algorithm proposed in this paper will outline a systematic approach for investigating abnormal hepatic function tests from asymptomatic workers.