Laboratory Analysis of Symptomatic and Asymptomatic Pregnant Patients with SARS-CoV-2 Infection

FISHER, Stephanie A.; GOLDSTEIN, Jeffery A.; MITHAL, Leena B.; ISAIA, Alexandra L.; SHANES, Elisheva D.; OTERO, Sebastian; MILLER, Emily S.

BACKGROUND: : Inflammatory biomarkers have been utilized to portend disease severity in non-pregnant individuals with SARS-CoV-2 infection. However, currently limited data are available, and with mixed results, to elucidate which inflammatory biomarkers may be most associated with clinical phenotype in pregnant patients. OBJECTIVE: : We aimed to compare laboratory findings among pregnant patients with severe acute respiratory syndrome coronavirus (SARS-CoV-2) by symptom status and disease severity. STUDY DESIGN: : We retrospectively evaluated pregnant patients at an urban academic U.S. hospital with positive polymerase-chain reaction SARS-CoV-2 testing between March and October 2020, performed for reported symptoms or universal screening on admission. In our hospital, all patients with SARS-CoV-2 were recommended to have baseline laboratory testing, including leukocyte, neutrophil and lymphocyte counts; aspartate and alanine aminotransferase; high sensitivity C-reactive protein (hsCRP); procalcitonin (PCT); lactate dehydrogenase (LDH); D-dimer; and ferritin. We performed multivariable logistic regression to evaluate peak laboratory abnormalities significantly associated with symptomatic SARS-CoV-2 infection and disease severity with gestational age at diagnosis, maternal age, and obesity as covariates. The sensitivity and specificity of laboratory abnormalities to identify symptomatic versus asymptomatic infection, and severe to critical disease versus mild to moderate disease, were calculated. RESULTS: : We identified 175 pregnant patients with SARS-CoV-2, of whom 100 (57%) were symptomatic; 17 (17%) of those who were symptomatic had severe to critical disease. Laboratory data was available for 128 patients, of whom 67 (52%) were symptomatic. Compared to asymptomatic people, symptomatic people were more likely to exhibit elevated hsCRP after adjusting for gestational age (aOR 5.67, 95% CI 1.42-22.52, sensitivity 81%, specificity 43%). In symptomatic individuals, transaminitis (aOR 5.67, 95% CI 1.27-25.43), elevated PCT (aOR 16.60, 95% CI 2.61-105.46), and elevated LDH (aOR 17.55, 95% CI 2.51-122.78) were independently associated with severe to critical disease compared to mild to moderate disease after adjusting for maternal age and obesity. Sensitivity for transaminitis, PCT elevation and LDH elevation was 47%, 87% and 53%, while specificity was 89%, 63% and 90%, respectively, for differentiating disease severity. CONCLUSION: : Inflammatory biomarkers in pregnant patients with SARS-CoV-2 exhibit vast heterogeneity, poor discriminative ability, and thereby limited clinical utility. Larger registry studies should evaluate which inflammatory biomarkers, accounting for pregnancy physiology, may be most useful for risk stratification and prognostication of pregnant patients with SARS-CoV-2 infection.