Prolonged corticosteroid therapy and cytomegalovirus infection in patients with severe COVID-19.

Systemic corticosteroid therapy is frequently used to treat coronavirus disease 2019 (COVID-19). However, its maximum duration without secondary infections remains unclear. We aimed to evaluate the utility of monitoring cytomegalovirus (CMV) infection in patients with COVID-19 and estimate the maximum duration of systemic corticosteroid therapy without secondary infections. We included 59 patients with severe COVID-19 without CMV infection on admission to the intensive care unit (ICU). All patients received systemic corticosteroid therapy under invasive mechanical ventilation, with examination for plasma CMV-deoxyribonucleic acid (DNA) levels during the ICU stay. We analyzed the correlations among patient characteristics, CMV infection, diseases, and patient mortality. CMV infections were newly identified in 15 (25.4%) patients; moreover, anti-CMV treatment was administered to six (10.2%) patients during the ICU stay. Four (6.8%) patients had secondary infection-related mortality. The cumulative incidences of CMV infection and anti-CMV treatment during the ICU stay were 26.8% (95% confidence interval [CI], 15.8%-39.0%) and 12.3% (95% CI, 4.8%-23.4%), respectively. Furthermore, the median duration of systemic corticosteroid therapy without CMV infection was 15 days (95% CI, 13-16 days). The presence of CMV infection was associated with mortality during the ICU stay (p = 0.003). Monitoring plasma CMV-DNA levels could facilitate the detection of secondary CMV infection due to prolonged systemic corticosteroid therapy. The duration of systemic corticosteroid therapy for COVID-19 should be limited.