Kombiglyze (metformin and saxagliptin)-induced hepatotoxicity in a patient with non-alcoholic fatty liver disease.

A 33-year-old man was referred with hyperosmotic symptoms of 4 weeks. Clinical examination showed palpable hepatomegaly and no stigmata of liver disease. Findings were random glucose 16.6 mmol/L, HbA1c 12.4%, triglyceride 6.2 mmol/L, normal LFTs and ultrasound liver: increased echogenicity. Management consisted of dietician referral and commencement of metformin 500 mg bd, diamicron MR 60 mg od, and fenofibrate 145 mg od. He was non-compliant, complaining of "heaviness of head" after consuming oral diabetic agents, without symptoms of hypoglycemia. Treatment was switched to Kombiglyze XR (saxaglipitin 5 mg + metformin 1000 mg) and empagliflozin 25 mg od. He presented 1 week later with generalised pruritus with ALT 307 IU/L and serum GGT 808 IU/L. Following this, a percutaneous liver biopsy was performed, revealing steatohepatitis and marked intra-hepatic cholestasis. Kombiglyze XR was withheld, with resolution of LFTs to baseline. Phenotypes of liver injury are categorised according to R value, defined as ratio ALT/ULN:ALP/ULN. R value of ≥5:hepatocellular injury, ≤2:cholestatic injury, 2-5:mixed-type injury. Here, R value points toward mixed type (R = 3.203). Hepatotoxicity in patients with NASH is difficult to diagnose, based on laboratory parameters. Liver histology was useful in indicating additional changes apart from NASH, causing liver derangement. The Rousal Uclaf Causality Assessment Method is a scoring method to determine the probability of drug induced liver injury. RUCAM score for this case was 6 (probable adverse drug reaction). Hepatotoxicity from saxagliptin not been reported prior. Clinicians need to be more vigilant, particularly in patients with NASH.