Possible metformin-induced hepatotoxicity.
BACKGROUND
Metformin hydrochloride is widely used for the treatment of type 2 diabetes mellitus (DM-2). To date, only 2 cases of possible metformin-induced hepatotoxicity (acute hepatitis) have been reported worldwide.


OBJECTIVE
The aim of this article was to report a case of serious hepatotoxicity possibly associated with metformin use in an elderly patient with DM-2.


METHODS
After receiving metformin 500 mg/d for 3 weeks, a 73-year-old Japanese woman weighing 33.5 kg with poorly controlled DM-2 presented with fatigue, jaundice, nausea, vomiting, anorexia, and abdominal pain. Laboratory analysis showed severe hepatotoxicity (elevated aspartate and alanine aminotransferases [AST and ALT, respectively], alkaline phosphatase [ALP], and total bilirubin concentrations). The history, clinical findings, laboratory features, and clinical course of this case, as well as the pharmacologic profile of metformin, are presented.


RESULTS
Immediate hospitalization and discontinuation of metformin treatment led to improvements in liver function (decreased AST, ALT, ALP, and total bilirubin concentrations) and resolution of the presented symptoms within 3 weeks. The probability of an adverse drug reaction (ADR), as assessed using the Naranjo ADR probability scale, in this case was 4 (probable).


CONCLUSIONS
In this case of an elderly woman with DM-2 who presented with symptoms of hepatotoxicity after 3 weeks of metformin treatment, metformin appeared to have caused a mixed-type (hepatocellular and cholestatic) hepatic damage. Although rare, severe hepatotoxicity might be associated with metformin use in some cases.
Kutoh
Eiji
E
Department of Internal Medicine, BMC, Beerse, Belgium. ekuto@excite.com
D056486:Chemical and Drug Induced Liver Injury / Q000000981:diagnostic imaging / Q000503:physiopathology*; D003924:Diabetes Mellitus, Type 2 / Q000150:complications / Q000188:drug therapy; D005260:Female; D006801:Humans; D007004:Hypoglycemic Agents / Q000009:adverse effects*; D008111:Liver Function Tests; D008687:Metformin / Q000009:adverse effects*; D008875:Middle Aged; D014057:Tomography, X-Ray Computed
D007004:Hypoglycemic Agents; D008687:Metformin