B-159 Method Comparison and Clinical Performance of a Novel, Fully Automated Multiplexed Microarray Immunoassay for the Detection of Celiac Disease Autoantibodies in a Pediatric Population

Abstract

This study assesses the agreement between the method and clinical performance of a novel, single-use, multiplexed microarray immunoassay—MosaiQ AiPlex® CD (AliveDx, Switzerland)—and established institutional standard of care (SOC) assays for identifying celiac disease (CD) via serological markers in a pediatric cohort. The MosaiQ AiPlex CD assay is currently in development and is designed for the semiquantitative and simultaneous detection of IgA and IgG autoantibodies against tissue transglutaminase (tTG) and deamidated gliadin peptide (DGP). Pediatric serum samples, which had been banked, de-identified, and clinically characterized, were included in the study. These samples were collected in an unbiased manner from patients either suspected of having or diagnosed with CD, ranging in age from under 6 years to over 18 years. Relevant clinical data such as adherence to a gluten-restricted diet, biopsy confirmation (when available), and clinical diagnosis of celiac status were recorded to assess clinical performance. Remnant samples were tested with both the investigational microarray assay and the equivalent in-house SOC assays. For each antibody specificity, negative and positive percent agreement (NPA and PPA) were calculated against SOC results. Clinical sensitivity and specificity were also determined. Double-sided 95% Confidence Intervals (CI) were calculated using the Clopper-Pearson Exact Method When compared with the respective devices, and excluding equivocal results, the investigational microarray demonstrated the following agreement:tTG IgA: PPA: 100% (30/30) (95% CI: 88.4, 100); NPA: 97.8% (132/135) (95% CI: 93.6, 99.4)DGP IgA: PPA: 66.7% (18/27) (95% CI: 46, 83.5); NPA: 96% (120/125) (95% CI: 90.9, 98.4)tTG IgG: PPA: 50% (2/4) (95% CI: 6.8, 93.2); NPA: 97.9% (140/143) (95% CI: 94, 99.4)DGP IgG: PPA: 92.3% (12/13) (95% CI: 64, 99.8); NPA: 81.4% (105/129) (95% CI: 73.6, 87.1) The investigational microarray also demonstrated clinical sensitivity and specificity in comparison to the SOC method (Table 1) The investigational MosaiQ AiPlex® CD microarray immunoassay exhibited strong clinical and methodological performance for the identification of celiac disease using clinically characterized remnant pediatric serum samples. This multiplex platform enables simultaneous, semi quantitative detection of key serological markers associated with celiac disease and may support a more streamlined approach to serologic evaluation.