Metformin Toxicity Masquerading As Acute Abdomen: A Clinical Reminder of Metformin-Associated Lactic Acidosis and Its Management.

Metformin is commonly used to manage type 2 diabetes mellitus (T2DM), but it is linked to a rare yet potentially life-threatening complication known as metformin-associated lactic acidosis (MALA). MALA typically occurs in patients with renal impairment, but may also be seen in those with liver disease, heart failure, or other metabolic disturbances. Management is primarily supportive, with aggressive interventions including decontamination and extracorporeal treatments such as continuous renal replacement therapy (CRRT) to reverse acidosis and clear metformin metabolites. A 72-year-old female with T2DM on metformin presented with severe diffuse abdominal pain, lethargy, and severe metabolic acidosis following a colonoscopy five days earlier, which was complicated by dehydration. Imaging ruled out pneumoperitoneum, and exploratory laparotomy revealed no ischemia or perforation. With suspicion of metformin toxicity, the patient was promptly started on CRRT, leading to rapid improvement. A metformin level confirmed the diagnosis of metformin toxicity. Although MALA is rare, it is critical to maintain a high index of suspicion in diabetic patients, particularly those with renal impairment or undergoing procedures that may exacerbate kidney injury. Early identification and initiation of extracorporeal treatment are crucial in managing severe metabolic acidosis and improving patient outcomes. This case underscores the importance of careful monitoring and management in diabetic patients with compromised renal function.