A comparative outcome analysis of covid-19 vs influenza infection in patients with acute leukemia
Authors: F. Modemann, C. Bokemeyer, W. Fiedler, S. Ghandili
Journal: HemaSphere (2021)

Background: Patients with acute leukemia and concomitant SARSCoV- 2 infection suffer from a more severe course of their infection than patients without underlying disease including a higher admission rate to ICU and a higher death rate. Similar observations have been made for concomitant influenza infections. Aims: The aim of this study is to compare the clinical courses of COVID- 19 and seasonal influenza in patients with acute leukemia (AL). This could help to find evidence for certain therapy modifications in AL patients with COVID-19 based on long lasting experience in patients with AL and influenza. Methods: This is a retrospective single center analysis including all patients with AL and concomitant influenza or SARS-CoV-2 infection who were treated in the department of oncology and hematology of the University Medical Center Hamburg-Eppendorf, Germany, between February 2013 until now. Data of the clinical course were collected from the patient's electronic medical records. Statistical analysis was performed by using IBM SPSS Statistics, version 26. Results: In the Influenza-group (n = 21), 71 % were male, the median age was 58 years (r: 20-81). 17 patients (81%) had acute myeloid leukemia (AML), four patients (19%) had acute lymphoblastic leukemia (ALL). 29% had newly diagnosed AL at influenza infection, 33% were in complete remission and 38% were under treatment due to refractory or relapsed disease. 95% were currently under chemotherapy treatment at diagnosis of influenza, 80% of them were treated with intensive chemotherapy. Median duration of aplasia was six days (r: 0-38), five patients had no aplasia during influenza infection. 18 patients were treated with Oseltamivir. 15 patients had an Influenza A with ten cases of H1N1, six patients had an Influenza B. The distribution in the COVID-19 group (n = 15) was similar: 73% were male, the median age was 59 years (r: 21-76). Nine patients (60%) had AML, six (40%) had ALL or acute lymphoblastic lymphoma. 27% had first diagnosis of AL, 27% were in complete remission, 46% had relapsed or refractory disease. All patients were under chemotherapy during SARS-CoV-2 positivity, 80% were treated with intensive chemotherapy protocols. Duration of aplasia during SARS-CoV-2 positivity was 0-36 days (median: 10 days), four patients had no aplasia. With 67% compared to 38% in the influenza group, we scored significantly more critical and severe courses in the COVID-19 group (p = 0.042, Mann Whitney U test) according to WHO-grading. We observed higher rates of pneumonia (93% vs. 67%) in COVID-19 patients with a rate of 40% of acute respiratory distress syndrome (ARDS) in the COVID-19 group compared to 19% of ARDS in the influenza-group. Rate of death due to COVID-19 after 90 days was 20% compared to influenza-associated deaths of 14%. Regardless of the type of infection (SARS-CoV-2 or influenza), we could show that a long aplasia duration is an adverse prognostic marker for 90-days mortality due to COVID-19 or influenza (p = 0.016, Mann Whitney U test). Summary/Conclusion: Patients with acute leukemia and concomitant SARS-CoV-2 diagnosis present with more severe clinical courses than patients with concomitant influenza, even though the rates of ARDS and critical disease of patients with AL and influenza are high. Therapy regimes with expected long duration aplasia should be possibly avoided in both patient cohorts due to higher mortality in patients with late regeneration of the blood count.