Metformin-Assocıated Lactic Acidosis Caused By A Suicide Attempt

Abstract

M etformin is a biguanide antidiabetic agent frequently used in the treatment of type-2 diabetes mellitus. [1] Metformin is an anti-hyperglycemic agent used to achieve euglycemia. Lactic acidosis can be seen in acute and chronic use of biguanides. Although the incidence of acidosis is 5-9 per 100.000, [3] metformin-associated lactic acidosis (MALA) has high mortality rates. [4, 5] Plasma half-life of metformin is approximately six hours. Its small molecular weight (165.8kD) and insignificant binding to plasma proteins increase the distribution volume of the drug (63-276 L). [6] Its sequestration in blood cells, such as erythrocytes and platelets, can extend its elimination half-life up to 17 hours. [7, 8] The major mechanism in the excretion of metformin is tubular secretion, and metformin is largely excreted unchanged in the urine. Its estimated renal clearance is 507±129 ml/min which is more than three times its creatinine clearance. However, in cases, such as the presence of underlying chronic renal failure and/or high doses of metformin used for suicidal intent, renal clearance is exceeded Metformin is a biguanide group drug commonly used in the treatment of Type 2 DM. Even though Metformin-Associated Lactic Acidosis (MALA) is not seen very frequently, MALA has a high mortality rate. This case is presented to draw attention to efficiency of hemodialysis and CVVHDF tin the treatment of MALA. A 25-year-old female patient was brought to the emergency service with abdominal pain and confusion. In her detailed history, it was learned that she took 100 tablets of metformin (1000 mg per tablet). Hemodialysis initiated because of severe metabolic acidosis, elevation of blood urea and hyperkalemia were seen in laboratory results. After that, patient was intubated because of low Glasgow Coma Scale (GCS:3) and vasopressor agent were started due to hypotension. In the intensive care unit, blood glucose was seen 44 mg dl-1 and treated with 10% dextrose solution. CVVHDF treatment was started because of anuria and metabolic acidosis. Patient who underwent CVVHDF treatment for 12-days transferred to nephrology service on the 23 rd day of the ICU admission with full consciousness and stabilized vitals. In conclusion, hemodialysis and CVVHDF should be the first treatment methods to be considered in patients with metforminassociated lactic acidosis. Renal replacement therapies, initiated rapidly and maintained for an adequate time period are promising in this high mortality rate cases.

Clinical presentations and prognosis of metformin-associated lactic acidosis patients in the intensive care unit: A 20-year survey

“…[5] Many studies have indicated that the most common symptoms are those associated with the abdomen, including vomiting, diarrhea, abdominal pain, and nausea. [22][23][24][25] However, some patients also presented with disturbed consciousness, [26] syncope, and breathing problems. [27] In accordance with the symptoms generally associated in patients with MALA, most clinical presentations observed during this study were classified as the head (40.24%), chest (41.46%), and abdomen (35.37%).…”