A simple method to identify undiagnosed drug-induced liver injury (DILI) and its application in oncology pharmacy practice

Aims To establish a simple method to identify chemotherapy-induced liver injury among oncological patients. To evaluate current clinical approach to elevated laboratory liver test results. Methods A total of 289 patients admitted to oncology department who had systemic chemotherapy episodes for cancer treatment from 1 January 2017 to 31 December 2017 were identified. With aid of healthcare information system, Hy's law was applied to laboratory liver test results to identify potential hepatocellular drug-induced liver injury cases. Medical record review was carried out among identified patients to exclude liver dysfunction of alternative causes. Current clinical approach to elevated laboratory liver tests was evaluated through medical record review. Results Of 289 patients who were treated by systemic chemotherapies, there were 123 patients with elevated laboratory liver tests, among which 8 patients were suspected as potential Hy's law cases. After medical record review, there were two patients determined with chemotherapy-associated liver injury, caused by 5-fluorouracil, leucovorin, irinotecan, and S-1 plus paclitaxel separately. Of eight potential Hy's law cases, seven (87.5%) patients were prescribed with (3)2 kinds of liver protectants and remained treated with traditional Chinese medicine for decoction. Conclusions A reliable and simple method to identify undiagnosed drug-induced liver injury was successfully established. An annual incidence of 0.69% of chemotherapy-associated liver injury in oncology department of the setting was found.