Assay of neonatal TSH from blood spots using the Architect i2000, an immunoassay analyzer

Objectives: To assess the Architect i2000 for measuring TSH from neonatal blood spots. Methods: Blood collected on filter paper was eluted and assayed on the Architect. Results: Recovery of TSH was close to 100%. Within-run and between-run precisions were 4.2–8.2% and 14.5–18.1%. Correlation with the Wallac Delphia method was excellent (r = 0.96). Linearity, sensitivity, and slope were 0–400 mU/l, 0.15 mU/l, and 0.86, respectively. The results obtained by this method on the Architect allowed us to differentiate normals from affected patients with the same reliability as the previous method. Conclusions: Measurement of TSH on the Architect is an excellent method for detecting congenital hypothyroidism.