Impact of acute kidney injury on metformin-associated lactic acidosis.
OBJECTIVE
Metformin has been shown to reduce diabetic complications in overweight patients, and is increasingly used to treat this condition. However, this agent is associated with a rare but serious risk of lactic acidosis.


METHODS
From January 2004 to November 2008, 11 cases of metformin-associated lactic acidosis were seen at a medical center in Taiwan. The patients' records were retrospectively reviewed with respect to clinical presentation, biochemical data, therapeutic strategies, and outcomes.


RESULTS
Ten out of 11 patients with acute kidney injury were enrolled in this study. From their pre-existing states, these patients would have been considered at low risk of developing lactic acidosis. However, all of them had acute intercurrent conditions that might compromise renal function. Among them, six patients were ventilated and five patients had severe hypotension with vasoactive support. Nine patients received renal replacement therapy to clear the acidosis and treat the renal failure. All but one of our patients survived. Recovery of renal function was the general rule in survivors.


CONCLUSIONS
Metformin-associated lactic acidosis is commonly accompanied with acute kidney injury. In spite of the severity of their illness, the outcome is favorable with intensive support of the cardiovascular, respiratory, and renal systems.
Wen
Yao-Ko
YK
Division of Nephrology, Department of Internal Medicine, Changhua Christian Medical Center, 135, Nanhsiao Street, Changhua, 500, Taiwan. wensnake1100@yahoo.com.tw
D000046:Academic Medical Centers; D000140:Acidosis, Lactic / Q000139:chemically induced* / Q000150:complications* / Q000503:physiopathology; D058186:Acute Kidney Injury / Q000209:etiology* / Q000401:mortality / Q000473:pathology; D000368:Aged; D000900:Anti-Bacterial Agents / Q000627:therapeutic use; D001639:Bicarbonates / Q000627:therapeutic use; D015331:Cohort Studies; D003131:Combined Modality Therapy; D016638:Critical Illness / Q000401:mortality / Q000628:therapy; D004636:Emergency Service, Hospital; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007677:Kidney Function Tests; D008297:Male; D008687:Metformin / Q000009:adverse effects* / Q000506:poisoning* / Q000627:therapeutic use; D008875:Middle Aged; D006435:Renal Dialysis / Q000379:methods; D012189:Retrospective Studies; D018570:Risk Assessment; D012720:Severity of Illness Index; D013406:Suicide, Attempted; D016019:Survival Analysis; D013624:Taiwan; D016896:Treatment Outcome
D000900:Anti-Bacterial Agents; D001639:Bicarbonates; D008687:Metformin