First Experience with Comparative Evaluation of Rossa Reagent Kits for Newborn Screening of 5q SMA and Primary Immunodeficiencies

The expansion of neonatal screening to include additional diseases requires the introduction of new diagnostic kits, which in turn necessitates multi-stage validation and comparative testing to evaluate their suitability for clinical use. In this study, we present the results of the first comparative assessment of a reagent kit for neonatal screening of 5q spinal muscular atrophy (SMA) and severe Tand/or B-cell primary immunodeficiencies (PID), manufactured by Rossa (Uzbekistan). The comparative analysis was performed using the EONIS reagent kit manufactured by Revvity (Finland) as a reference method. Preliminary results demonstrate concordance between the two approaches in detecting homozygous deletion of exon 7 of the SMN1 gene and in quantifying TREC and KREC levels in dried blood spot samples from newborns. These findings support the feasibility of the tested reagent kit and provide a basis for further validation studies of the Rossa kit to assess its analytical performance and define appropriate cutoff values for implementation in neonatal screening programs.

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