The copy quantities of TRECs as a biomarker for screening SCID in newborns：a meta-analysis

Abstract

Purpose Severe combined immunodeficiency (SCID) threatens the newborns' living qualities. The aim of our study is to evaluate the the value of detecting the copy quantities of T-cell receptor excision circles (TRECs) in screening for the newborns' SCID. Methods We searched eligible studies in PubMed, Web of science, EMBASE, the Cochrane Library, China National Knowledge Infrastructure (CNKI) and chose the Endnote software to filter the whole studies. Meta-analysis was conducted with meta-disc 1.4 and STATA 12.0 software. We used sensitivity and false positive rate (FPR) to evaluate this detecting method; subgroup analysis to explore the sources of heterogeneity. The literature quality was assessed by the quality assessment of diagnostic accuracy studies (QUADAS-Ⅱ). Results Fifteen studies were enrolled containing 3,570 cases in the decreased TREC copy quantities group and 12,186,899 cases in control group. All the included studies are of high quality. The heterogeneity in Diagnostic Odds Ratio (DOR) is 77.9%. The summarized estimates revealed that the pooled sensitivity is 100% (95% confidence interval (CI): 99–100%), the false positive rate is 0.00 (95% CI: 0.00–0.00) and Positive Predict Value (PPV) is 0.14 (95% CI: 0.08-0.19). The current evidence shows detecting the copy quantities of TRECs has the screening value with a high sensitivity and positive likelihood ratio (LR+) for newborns' SCID without published bias (p>0.05). Our result suggests 90 and 40 copies/ul of TRECs as the primary and secondary cut-off value. Conclusion Detecting the individual TREC contents could be used as the premise to diagnosis the newborns' SCID.