Thiamine responsive lactic acidosis in patients not in shock: A case series and literature review.

Lactic acidosis is a common feature of patients presenting with sepsis, volume depletion due to ketoacidosis, tissue ischemia, shock and liver disease. These cases typically presume tissue hypoxia and anaerobic metabolism leading to lactic acidosis. Thiamine deficiency is an underappreciated cause of type B lactic acidosis, which is not caused by anaerobic metabolism. We present a case series of 11 patients admitted to the medicine service who were not in shock, and who had a lactic acidosis (average of 4.5 mmol/L) that improved after thiamine administration (resolving to <2 mmol/L in 10 of 11 patients). We then review thiamine and lactate physiology, and provide clinicians with evidence based recommendations to consider when treating patients with persistent lactic acidosis who are vitally stable.