[Rapid determination by immunoassay of glycosylated hemoglobin in capillary blood compared to an affinity method for boronate and ion capturing on venous blood].

Measurement of glycosylated haemoglobin has become an essential tool in the management of diabetic patients. A recently developed device allows the rapid immuno-assay of HbA1c in 1 microliter capillary blood obtained by a finger prick. In 100 ambulatory diabetic patients, we compared the results obtained with this method to those obtained in venous blood using a standard affinity chromatography laboratory method. Although both methods correlated (r = 0.88, p < 0.001), the mean +/- SD levels respectively obtained differed slightly (7.6 +/- 1.5 vs 79 +/- 1.4% p < 0.001). The 95% confidence interval of the difference was [-0.41. -0.14]. Considering a cut-off HbA1c value of 8%, as indicative of the need for treatment adjustment, 33 patients with the capillary blood immuno-assay method and 42 with the venous-blood affinity chromatography method were above that limit (Mc Nemar test, p < 0.05). In conclusion, the rapid assay of HbA1c in capillary blood can be useful for the management of some diabetic patients but the results are not readily exchangeable with those obtained from other standardized laboratory methods. Consequently, specific ranges and clinical decision limits must be determined.