OBJECTIVETo investigate the clinical characteristics of the adaptation phenomenon occurring in antituberculosis drug-induced liver injury.

METHODSOur department's clinical records were searched using the standardized diagnostic criteria and monitoring programs parameters of drug-induced liver injury to identify cases with the adaptation phenomenon. The 32 identified cases were classified according to whether or not the drug was discontinued after development of the drug-induced liver injury: withdrawal group (n = 11) and continuing group (n = 21). The types of patients with adaptation phenomenon were assessed to determine the relationship between liver injury and development time, and between the severity grade of liver injury (determined by biomarker expression) and symptoms.

RESULTSAll of the 32 cases of drug-induced liver injury with the adaptation phenomenon were classified as the hepatocellular injury type. The average overall incubation period was 16.59+/-13.05 days (range: 6-60 days), while that of the continuing group was 17.05 +/-13.71 days (6-60 days) and that of the withdrawal group was 16.46+/-12.09 days (6-43 days). The average overall time for peak transaminase levels to decrease to the normal range was 11.34 +/-5.97 days (6-30 days), while that of the continuing group was 11.20+/-5.92 days (6-30 days) and that of the withdrawal group was 11.91/-6.20 days (7-30 days). Thirty of the overall patients showed grade 1 degree of liver injury and only two showed grade 2.

CONCLUSIONThe clinical characteristics of the adaptation phenomenon include a transient increase in biochemical indicators of the antituberculosis drug-induced liver injury. It is important to understand the clinical variations in the adaptation phenomenon to formulate feasible and appropriate programs for monitoring and prevention.