Characterization of persistent COVID-19: An emerging post- pandemic crisis in immunocompromised patients. An observational cohort study

Introduction Persistent coronavirus disease 2019 (pCOVID-19) is an emerging complication of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, particularly among immunocompromised patients. We aimed to characterize our experience, focusing on diagnostic and therapeutic findings. Methods A large, retrospective, cross-sectional cohort study was conducted on all patients diagnosed with pCOVID-19 at a university-affiliated tertiary medical center between May 2020 and February 2024. Follow-up ended in December 2024. Inclusion criteria were evidence of ongoing SARS-CoV-2 replication beyond 14 days, persistent or relapsing symptoms, and immunocompromised status. The main outcome measures were risk factors, clinical manifestations, laboratory findings, diagnostic methods, treatment approaches, and mortality rate of the disease. Results The cohort comprised 81 patients (49 male, 32 female), of mean age 66.5 ± 12.6 years. Hematological malignancies (62.9%) and solid organ transplantation (18.5%) were the most common immunosuppressive conditions, and anti-B-cell agents (75.3%) were the most frequently used immunosuppressive treatments. The most prevalent symptoms were fever (80.2%), cough (79.0%), dyspnea (54.3%), and weakness (49.3%). Notably, bronchoalveolar lavage was required for virologic confirmation in 19.7% of patients. The average time to diagnosis was 100 ± 18.7 days. Treatment during the pCOVID-19 phase included increased use of antiviral agents (83.9%) and convalescent plasma (95.0%). The mortality rate was 24.6%; median time from diagnosis to death, predominantly due to respiratory failure, was 32.5 days (range: 10–882 days). Discussion Our study showed that pCOVID-19 is strongly associated with immunosuppressive conditions and therapies. Fever and respiratory symptoms were the most common presentations. The diagnostic and treatment challenges raise the need for a multidisciplinary team. The mortality rate was high. The main reasons for death were respiratory failure and secondary infections.