P1555: covid‑19 infection in patients with hematological malignancies: a single-centre survey during the latest omicron wave in china

Topic: 30. Infections in hematology (incl. supportive care/therapy) Background: Patients with hematological malignancies (HMs) are at high risk of COVID-19 disease. Given the SARS-CoV-2 Omicron variant spread in Beijing since December 2022, a better understanding of risk factors for adverse outcomes may improve the clinical management of HM patients. Aims: The objective of this study was to assess the epidemiology and outcomes of COVID-19 in HM patients. Methods: This study included consecutive patients (aged ≥18 years) with HM and laboratory-confirmed COVID-19 who were admitted to our hospital between December 7 and December 25, 2022, with the data cutoff for the analyses on January 8, 2023. COVID-19 genomes were determined through next-generation high-throughput sequencing (NGS). Results: The study included 412 cases, mainly represented by acute leukemia, chronic myeloid leukemia (CML), plasma cell disorders and lymphoma and chronic lymphocytic leukemia (CLL). Median follow-up was 25 days [interquartile range (IQR), 22-28; range 10-32]. Overall, 111 patients (26.9%) had at least one comorbidity, including coronary heart disease, chronic pulmonary disease, hypertension, diabetes mellitus, thyroid disease, liver disease, and renal impairment. At the onset of COVID-19 infection, 59 patients (14.3%) had agranulocytosis. Moreover, 269 patients (65.3%) had received at least one dose of the COVID-19 vaccine at COVID-19 diagnosis. Eighteen of 20 samples (90%) of viral nucleic acid were verified through NGS to be Omicron subvariant BF.7, with 10 cases of severe illness, six cases of critical illness and two cases of moderate illness. Two other samples were verified to be BA.5.2 and BA.5.1, represented by mild illness and severe illness, respectively. COVID-19 infection was determined to be critical in six patients (1.5%), severe in 16 (3.9%), moderate in 21 (5.1%), and mild and asymptomatic in 369 (89.6%) patients. Among the 86 cases with advanced malignancies (HM status of onset, active disease, and refractory/resistant), 17.6% of patients developed severe/critical COVID-19, which was significantly higher than in patients with stable malignancies (2.70%, p = 0.000), with a high mortality rate (10.47% vs. 0%, p = 0.000) and poor 30-day OS (74.2% vs. 100.0%, p <0.0001, Figure 1A). Of the 22 severe/critical cases [acute leukemia (n = 9), myelodysplastic syndrome (n = 1), CML (n=1), plasma cell disorders (n = 8), CLL (n = 2), and myelofibrosis (n = 1)], nineteen (19/22, 86.4%) received antiviral treatment (18 received Paxlovid, one received Azifudine) and 18 (18/19, 94.7%) had controlled pneumonia. COVID-19 nucleic acid test of 15 cases turned negative in a median of 14 days (IQR, 11-18 days, range 6-22 days), while seven days (IQR, 6-9 days, range 4-16 days, p = 0.000) for non-severe/critical cases. Seven cases did not turn negative until the end of follow-up, five of whom died with sustained positive test results (the median time from COVID-19 diagnosis to death was 20 days, IQR, 12.5-30 days, range 12-30 days). Overall, nine patients (2.2%) died. The primary cause of death was progressive HM in four patients, and a combination of both COVID-19 and HM in five patients. Considering the different HMs, all deaths occurred in acute leukemia cases (Figure 1B). Multivariate analysis showed that age above 65 years, comorbidities, and advanced malignancy were correlated with severe/critical COVID-19 in HM patients. Moreover, comorbidities, advanced malignancy, and severe/critical illness were correlated with mortality. Image：Summary/Conclusion: This study sheds light on poor outcomes among COVID-19 HM patients with the leading cause of advanced malignancy. The role of targeted antiviral treatment in severe/critical COVID-19 cases should be confirmed by larger sample size studies. Keywords: COVID-19, Hematological malignancy