Neonatal screening for severe combined immunodeficiency (SCID) with quantification of TREC and KREC using QRT-PCR: a systematic review

Abstract

Severe Combined Immunodeficiency (SCID) is a primary lethal disease, when early treatment is not employed, diagnosis through the analysis of the T cell receptor excision circle (TREC) and the kappa recombination circle excision (KREC). Using Guthrie cards and filter paper, information based on the real-time polymerase chain reaction (PCR) molecular test (qRT PCR) is extracted to simultaneously assess the deficiencies of B cells and T and track immunological changes. Thus, the objective of this systematic review was to verify the sensitivity and specificity of using qRT-PCR, in TREC and KREC, in the diagnosis of SCID, according to publications in the PUBMED and SCIELO databases, between 2011 and 2021, resulting in 30 articles complete, after applying the methodology, in which it was possibleto conclude that the quantification of TRECs and KRECs, using the qRT-PCR test, was efficient in detecting SCIDs and validated in several countries, however, still little used in Brazil, showing low diagnosis of inborn errors of immunity and high mortality rate in the first year of life.