SARS-CoV-2 IgM and IgG serology and clinical outcomes in COVID-19 patients

BackgroundThe SARS-CoV-2 virus has become pandemic for the last 2 years. Inflammatory response to the virus leads to organ dysfunction and death. Predicting the severity of inflammatory response helps in managing critical patients using serology tests IgG and IgM. We conducted a longitudinal study to correlate serum SARS-CoV-2 IgM and IgG serology with clinical outcomes in COVID-19 patients.MethodsWe analyzed patient data from March to December of 2020 for those who were admitted at AIIMS Rishikesh. Clinical and laboratory data of these patients were collected from the e-hospital portal and analysed. Correlation was seen with clinical outcomes and was assessed using MS Excel 2010 and SPSS software.ResultsOut of 494 patients, the mean age of patients was 48.95 ± 16.40 years and there were more male patients in the study (66.0%). The patients were classified into 4 groups; mild-moderate 328 (67.1%), severe 131 (26.8%) and critical 30 (6.1%). The mean duration from symptom onset to serology testing was 19.87 ± 30.53 days. In-hospital mortality was observed in 25.1% patients. The seropositivity rate (i.e., either IgG or IgM >10 AU) was 50%. There was a significant difference between the 2 groups in terms of IgM Levels (AU/mL) (W = 33428.000, p = ConclusionSerology (IgM and IgG) levels are high in RTPCR positive group compared to clinical COVID-19. However, serology cannot be useful for the prediction of disease outcomes except few situations. The study also highlights the importance of doing serology at a particular time as antibody titres vary with the duration of the disease.