OBJECTIVETo evaluate an enzymatic method for determining serum beta-hydroxybutyrate (beta-HB) with the National Committee for Clinical Laboratory Standards (NCCLS) projects, and to discuss its clinical values in diabetic ketoacidosis (DKA).

METHODSThe precision, accuracy, specificity, linearity and interference of the enzymatic method were analyzed. This method was used to determine serum beta-HB in 60 cases of normals, 50 cases of diabetes, and 34 cases of DKA by autochemistry analyzer.

RESULTSEnzymatic beta-HB assay was precise (within-run CV, day-to-day CV, and total CV < 5%). The linearity studies showed the method was linear up to 4 mmol/L. Recovery rate was 98.5%-104.1%. Hemolysis (Hemoglobin up to 18.2 g/L), icteric samples with total bilirubin up to 224 mumol/L, and lipemia up to triglyceride concentration of 2.28 mmol/L did not interfere with the beta-HB results in this method. Serum beta-HB levels were significantly elevated in DKA patients compared with DM patients and controls (P < 0.01). Positive rate of serum beta-HB in DKA patients was significantly higher than that of urinary ketone (P < 0.05).

CONCLUSIONSEnzymatic method is convenient and reliable, allows full automation, and is rapid enough to be used for both routine and urgent determinations of serum beta-HB. It can be used in diagnosing and monitoring treatment of DKA.