EVALUATION OF GLYCEMIC CONTROL LIMITS USING THE AMES-DCA-2000 HBA(1C)ANALYZER

The Ames DCA 2000 is a benchtop analyser that measures HbA(1c) by an a gglutination inhibition immunoassay using a monoclonal antibody. Labor atory and nursing staff measured HbA(1c) on-site in 78 patients with T ype 1 diabetes at the outpatient clinic. Significant correlations were noted with both the Coming Glytrac total HbA(1) assay (r = 0.89) and the Novoclone assay for HbA(1c) (r = 0.95). Mean within-assay CV was 1 .6 % and 3.0 % at HbA(1c) of 5.4 % and 13.0 %, respectively, while bet ween-assay CVs were 4.2 % and 3.8 %. These results are as good as our routine laboratory method based on the Corning HbA(1) assay. Locally d erived reference population data for HbA(1c) were produced and patient s were assigned to categories of good, acceptable, and poor glycaemic control using conventional recommendations for Type 2 diabetes. There was poor agreement between the methods, with only 22 % of patients ach ieving good/acceptable control using the DCA 2000, while 46 % of patie nts had an HbA(1) in this range. It appears that the convention for de rivation of control limits for HbA(1) does not hold for this HbA(1c) a ssay.