Interest of Clinitek (R) microalbumin in screening for microalbuminuria: Results of a multicentre study in 302 diabetic patients

A prospective survey was performed in 302 consecutive diabetic outpatients from 3 French diabetic centres to study the sensitivity and specificity of screening for microalbuminuria using Clinitek(R) Microalbumin. Urinary samp les with positive (at least one +) proteinuria, hematuria, leucocyturia, or nitrates using the Multistix(R) strip were excluded from the study. Result s obtained with Clinitek(R) Microalbumin were compared to those observed wi th the reference method of the biological laboratory of the centre on the s ame urinary sample. A positive result was defined as an albumin-to-creatini ne ratio greater than or equal to 30 mg/g. Results were described in terms of sensitivity, specificity, positive and negative predictive values and li kelihood ratio. Agreement rates were compared with the Kappa test. In the study population, 48 patients (17%) had a positive microalbuminuria with reference assay. However, different rates were found in each site (25% , 11%, and 15%, respectively, p < 0.001). Using the Clinitek(R) Microalbumi n, a positive result was found among 86 patients (29%), (39%, 26%, and 23%, respectively). A good agreement was observed in the popula tion as a whole (81%, K = 0.47 +/- 0.06) and in each site (77%, 81%, 84%, respectively). S ensitivity was 79% (82%, 80%, 75%), specificity 81% (76%, 81%, 85%), positi ve predictive value 46% (53%, 35%, 46%), negative predictive value 95% (93% , 97%, 95%), and positive likelihood ratio 4.2 (3.4, 4.3, 5.0, respectively ). Due to the excellent negative predictive value, these results suggest that Clinitek(R) Microalbumin is a good screening test for microalbuminuria. Pos itive results should be confirmed using a reference assay.