Potential Use of Pregnancy-associated Plasma Protein-A and IMA as Biomarkers for the Early Stage of COVID-19

Abstract BackgroundThis study has been undertaken with the urgent need for exploring reliable biomarkers for early infection of SARS-CoV-2. We performed a retrospective study analyzing the serum levels of the cardiovascular biomarkers N-terminal pro-B natriuretic peptide (NT-proBNP), cardiac troponin T (cTnT), Ischemia Modified Albumin (IMA) and pregnancy associated plasma protein A (PAPP-A), in 84 patients with COVID-19. MethodsPatients were divided in three groups according to their RT-qPCR and IgG values in acute infection (n=35), early infection (n=25) or control subjects (n=24). Levels of biomarkers were analyzed in patient’s serum samples by commercially available ELISA kits.ResultsMultivariate analysis and Receiver Operating Characteristic (ROC) curve showed that IMA and PAPP-A, had an excellent discrimination value for the early stage of COVID-19. Serum levels of IMA in early SARS-CoV-2 infected patients were significantly higher than in the control group with an area under the ROC curve (AUC) value of 0.94 (95% confidence interval (CI): 0.881- 0.999). Likewise, the serum level of PAPP-A was significantly higher in patients with early infection than in controls [AUC = 0.801 (95% CI: 0.673–0.929)]. The combined use of IMA and PAPP-A enhanced the sensitivity for total SARS-CoV-2 infected patients to 93%. ConclusionsThese results suggest that the levels of PAPP-A and IMA might be used as efficient biomarkers for the early stage of COVID-19 with high sensitivity and specificity. Importantly, when monitoring pregnancy and cardiovascular diseases by PAPP-A or IMA levels, an infection by SARS-CoV-2 should be discarded for proper interpretation of the results.