[Changes of lactate levels in diabetic ketoacidosis and in newly diagnosed type 1 diabetes mellitus].

Introduction: It is known that lactate concentration is increased in diabetic ketoacidosis (DKA), however, the pathophysiology and kinetics of lactate changes are still unclear. Normally, L-lactate is the major form in the human body. According to previous data, also D- and L-lactate might be increased in hyperglycaemic disorders. Aim: We aimed to describe the kinetics and mechanisms of lactate concentration changes in ketoacidosis and newly diagnosed diabetes. Method: We performed a prospective study, including 5-18-year-old children with ketoacidosis (DKA, n = 13) and with newly diagnosed type 1 diabetes without ketoacidosis (T1DM, n = 6). We performed routine blood gas analysis 0-12-24-48 hours after admission, which also measured L-lactate levels. We also determined total venous serum lactate level by gas chromatography-mass spectrometry. Results: Initial plasma lactate concentration was increased in ketoacidosis as compared to the newly diagnosed diabetes group (p<0.05). After 12 h of rehydration, lactate levels were greatly reduced in ketoacidotic patients but after 24-48 h it was repeatedly increased (all p<0.01). In the 0-12 h phase, total serum lactate level was higher than L-lactate level, referring to D-lactate production. Conclusion: We described two L-lactate peaks in ketoacidosis. In the first 12 hours anaerobic glycolysis seems to have major role in hyperlactataemia. We assume that stimulated aerobic glycolysis leads to the second lactate peak. However, D-lactate is not routinely measured, it may contribute to the initial hyperlactataemia in both groups and is comparable to L-lactate production in ketoacidosis. Orv Hetil. 2019; 160(45): 1784-1790.