A case report of metformin-associated lactic acidosis.

Key Clinical Message: Metformin-associated lactic acidosis is a rare but serious complication in patients with type 2 diabetes, especially those with multiple health conditions. Prompt recognition and treatment, including potential renal replacement therapy, are crucial for managing severe acidosis and improving patient outcomes.

Abstract: Metformin (MTF) is commonly prescribed as a first-line treatment for diabetes, effectively preventing microvascular and macrovascular complications. However, metformin-associated lactic acidosis is a rare yet severe complication, associated with a mortality rate of up to 50%. We encountered a case involving a 73-year-old woman with type 2 diabetes, mental illness, and hypothyroidism, who developed life-threatening lactic acidosis while on metformin therapy. Upon presenting to the emergency department with complaints of weakness, nausea, and decreased urination for 5 days, she also reported abdominal pain and shortness of breath. Hypotension was noted with a blood pressure of 80/50 mmHg. Initial laboratory results revealed severe acidosis, prompting discontinuation of MTF. Despite resuscitation efforts and vasopressor therapy, severe acidemia persisted, leading to the initiation of renal replacement therapy. Following treatment with continuous renal replacement therapy, her acidemia resolved, and she was discharged from the hospital on the sixth day without complications, with normal kidney function.