In December 2019, cases of severe respiratory infection were reported in Wuhan, China. The disease was caused by a new, previously undescribed coronavirus, structurally similar to the then known SARS-CoV virus. The World Health Organization has named the new virus SARS-CoV-2 and the disease it causes COVID-19. The problem of COVID-19 is exacerbated by the rapid spread of the SARS-CoV-2 virus and the development of life-threatening complications, the main of which is pneumonia. Due to the severity of the condition, from 5 to 10 % of patients are treated in intensive care units.

SARS-CoV-2 initially attacks the respiratory system and causes symptoms such as fever, vomiting, headache, dizziness, general weakness, and diarrhea. Then these symptoms intensify in different directions, and the disease can often lead to death.

Initially, only a few methods of symptomatic treatment were available and clinical trials of drugs that had previously shown their effectiveness against infection with the MERS-CoV and SARS-CoV viruses began. Temporary recommendations have appeared suggesting the use of some drugs both in monotherapy and in combination.

In patients with hematologic malignancies, the immune response to the SARS-CoV-2 coronavirus is significantly reduced, which explains the high mortality rate (up to 38 %) of these patients hospitalized for SARS-CoV-2 infection. Recently, antiviral drugs and monoclonal antibodies have become available for pre- or post-exposure prophylaxis, as well as for early treatment of COVID-19. These treatments should be offered to patients at high risk of severe COVID-19 and to those who have not responded to vaccination. However, as changes in the genetic structure of the virus accumulate, some treatments may lose their clinical effectiveness against new variants.

The combination of hematological malignancies and new coronavirus infection causes a more severe course of COVID-19 compared to the population and high mortality. Factors for an unfavorable prognosis for new coronavirus infection in patients with hematological malignancies include age over 60 years, a high comorbidity index, diagnoses such as acute leukemia, especially acute myeloid leukemia and myelodysplastic syndrome, disease status (relapse, progression, as well as newly diagnosed acute leukemia), severe COVID-19, agranulocytosis (myelotoxic or tumor).

Background. Acute myeloid leukemia (AML) is a highly aggressive oncological disease of the blood and bone marrow, requiring extremely toxic chemotherapy and massive supportive treatment to achieve stable remission. Currently, there is no work to provide medical care to these patients with a high risk of coronavirus infection. This paper presents treatment results of a large AML patient cohort during the COVID-19 pandemic.

Aim. To assess the clinical features of coronavirus infection in AML patients.

Materials and methods. A retrospective cohort study included patients hospitalized at City Clinical Hospital No. 52 (Moscow) between March 2020 and March 2022. Study inclusion criteria: 1) AML diagnosed within the last 3 years before the development of the COVID-19 pandemic; 2) age over 18 years; 3) laboratory confirmed SARS-CoV-2. AML status (newly diagnosed AML, relapse/refractory disease, remission), age, gender, comorbidity index, previous AML therapy and its outcomes were also assessed.

Results. Among 218 patients with acute leukemia, 60 (27.5 %) patients had acute lymphoid leukemia, 158 (72.5 %) had AML. Patients with acute promyelocytic leukemia were allocated to a separate group - 20 (9 %) patients. The statistical data of the remaining 138 (63.5 %) patients with AML, their survival and mortality rates were assessed, and the main prognostic factors influencing the mortality and severity of coronavirus infection were identified. Also, our own results were compared with world statistics.

Conclusion. Coronavirus infection in AML patients significantly worsens the prognosis. The main factors influencing the severity of coronavirus infection and survival and mortality rates are age, somatic status of patients due to the presence of concomitant chronic diseases, the development of deep hypoplasia of hematopoiesis, and the active AML status (disease onset or resistant course).

Patients with acute leukemia are one of the most vulnerable risk groups for infection with SARS-CoV-2 and severe course of coronavirus infection. During the first 2 years of the pandemic, the mortality rate of patients with acute leukemia was 11-48 %, depending on leukemia type, and only reached population levels in 2022. Risk factors for severe COVID-19 in patients with acute leukemia are old age, concomitant cardiac pathology, metabolic syndrome, and the absence of acute leukemia remission. Chemotherapy administered one month before hospitalization with COVID-19 diagnosis showed statistical significance in influencing hospital mortality only in the group of patients with acute myeloid leukemia. Despite this, the international medical community has recommended delaying the start of chemotherapy until clinical symptoms of coronavirus infection have completely resolved and a negative test result for SARS-CoV-2 has been obtained for all types of leukemia. Currently, the most optimal tactic is to prevent SARS-CoV-2 infection by vaccinating patients with acute leukemia receiving antitumor treatment. If the immunological response to vaccination is insufficient, it is possible to use virus-neutralizing monoclonal antibodies as a safe and effective method of primary prevention of COVID-19.

Aim. To study the course of COVID-19 (COronaVIrus Disease 2019) in elderly patients with acute myeloid leukemia (AML), to analyze risk factors for unfavorable outcome.

Materials and methods. The paper presents our own experience in the treatment of elderly (age ≥65 years) patients with AML and concomitant coronavirus infection in the hematology departments of City Clinical Hospital No. 52 (Moscow) from March 2020 to June 2022. The diagnosis of COVID-19 was considered confirmed based on a positive result of the polymerase chain reaction of an oropharyngeal and nasopharyngeal swab for SARS-CoV-2 and/or a typical radiological picture on a computed tomogram of the lungs.

Results. An analysis of clinical, laboratory and instrumental data of 59 patients (30 (51 %) men, 29 (49 %) women) with AML and COVID-19 was carried out. All patients were treated for COVID-19 in accordance with the Temporary guidelines “Prevention, diagnosis and treatment of new coronavirus infection (COVID-19)” of the Russian Ministry of Health. Median age was 71 (65-91) years. AML was first verified in 27 % of hospitalized patients; 12 % were in remission of the disease. A month before hospitalization, 36 % of patients received antitumor therapy, and 19 % of patients had refractory AML. 17 % of hospitalized patients received antitumor therapy with cytarabine in small doses for vital indications. Death was recorded in 64 % of cases, in 24 % the cause of death was severe COVID-19. The unfavorable outcome was influenced by addition of secondary bacterial flora, refractory AML course and elderly age of patients.

Conclusion. Pre-exposure prophylaxis with monoclonal antibodies and vaccination of patients may be the main methods of preventing infection and severe course of COVID-19.

Background. At the end of 2019, a new coronavirus infection caused by the SARS-CoV-2 virus was registered. In March 2020, the first cases of COVID-19 were detected in Moscow. Patients with chronic lymphocytic leukemia, characterized by profound immune dysfunction, have risk factors for severe viral disease.

Aim. To identify risk factors for hospital mortality and severe course of COVID-19, as well as to optimize therapeutic and preventive measures.

Materials and methods. The analysis included 238 patients (142 (59 %) men and 96 (41 %) women) with chronic lymphocytic leukemia and COVID-19 with a median age of 66 (37-90) years, who were hospitalized at City Clinical Hospital No. 52 (Moscow) between April 2020 and April 2023. To compare hospital mortality and severity of COVID-19, patients were divided into 2 groups depending on the hospitalization period: 2020-2021 and 2022-2023, which correlates with the prevalence of some SARS-CoV-2 variants from December 2021 and changes in Moscow epidemiological situation.

Results. Overall hospital mortality rate in 2020-2021 was 25 % (n = 45). Age over 73 years was a significant unfavorable factor in men. Cardiovascular diseases increase the risk of death by 2.3 times. Patients with a Charlson Comorbidity Index of 6 or more have a 2.2 times greater risk of death. A history of 1 or more lines of immunochemotherapy increased the risk of hospital mortality by 1.5 times. Relapse/progression of the disease were factors of unfavorable prognosis for patient survival. Binet stage C also showed a significant unfavorable prognosis. When studying all cases of death (n = 51), complications such as myelotoxic agranulocytosis, secondary bacterial complications and severe interstitial pulmonary damage >75 % were identified.

Conclusion. Coronavirus infection caused by SARS-CoV-2 represents an infectious threat among patients with chronic lymphocytic leukemia and may affect the regimen and tactics of antitumor therapy. The use of a full range of preventive measures, vaccination and pre-exposure prophylaxis in this cohort of patients is of great importance.

Background. Coronavirus disease (COVID-19), caused by SARS-CoV-2, presents new challenges to hematologists, highlighting the vulnerability of patients with hematological malignancies, in particular with diffuse large B-cell lymphoma (DLBCL). Identification of hospital mortality risk factors is necessary for subsequent stratification of patients into risk groups, which will allow further risk-based therapy.

Aim. To develop a prognostic model and identify risk factors for hospital mortality in patients with DLBCL associated with COVID-19.

Materials and methods. The interim retrospective study included 112 patients with an immunohistochemically confirmed diagnosis of DLBCL, coronavirus infection verified based on polymerase chain reaction (PCR) for SARS-CoV-2, and viral pneumonia associated with COVID-19. To determine the risk factors for hospital mortality, a multivariate (logistic regression) statistical analysis was performed. The study end point was a binary variable - the patient vital status (discharged alive or died).

Results and conclusion. Of the 112 patients, 24 died. Due to the limited number of patients compared to the number of predictors and to avoid overfitting, a two-stage approach to constructing a predictive model was used. In univariate analysis, statistically significant during hospitalization were the hematological disease status (complete remission/partial remission, progression/relapse, de novo), positive PCR result, C-reactive protein level >6 mg/L, platelets <100 thousand/pL, hemoglobin <120 g/L, albumin <35 g/L, lactate dehydrogenase >248 U/L, D-dimer >500 ng/mL and the degree of lung tissue damage according to computed tomography >50 % (grade II and above), respiratory failure I degrees and higher. The final model was constructed by minimizing the Akaike information criterion. The final model included a positive PCR result, stage II respiratory failure, hematologic disease status (relapse/progression), and albumin level at the time of hospital admission.

Background. In March 2020, doctors faced the problem of severe COVID-19 coronavirus infection in patients with multiple myeloma. This required a review of issues related to the selection of patients, the development of new preventive and therapeutic tactics aimed at treating infectious and immunological complications in patients of this category, depending on the nature and status of the underlying disease and the timing of treatment.

Aim. To assess the severity of multiple myeloma, the most common complications and features of the COVID-19 course in patients with multiple myeloma at different therapy stages (disease onset, remission, maintenance therapy, progression/refractory disease).

Materials and methods. From March 2020 to May 2022, 89 patients diagnosed with multiple myeloma and coronavirus infection caused by the SARS-CoV-2 virus were hospitalized at City Clinical Hospital No. 52 (Moscow). After assessing the severity, a decision was made on patient management, and if necessary, according to indications, the patient received specific antitumor therapy for multiple myeloma and treatment of coronavirus infection simultaneously.

Results. Treatment for coronavirus infection was carried out in accordance with the clinical recommendations of the Russian Ministry of Health at that time. It included antiviral, anticoagulant therapy, transfusions of fresh frozen convalescent plasma with a high titer of antibodies, genetically engineered biological drugs and monoclonal antibodies; if necessary, patients received antibacterial and antifungal, hormonal therapy. Specific chemotherapy was also administered according to indications.

Conclusion. Patients with multiple myeloma are at higher risk of severe COVID-19 infection. Today, the problem of developing adequate therapeutic tactics for managing patients with multiple myeloma and coronavirus infection still remains relevant. It is necessary to develop an optimal protocol for the management of such patients, including an assessment of prognostic factors, identification of clearly defined indications and contraindications for chemotherapy, and a description of supportive therapy.

Background. In March 2020, oncohematologists faced the problem of severe COVID-19 coronavirus infection in patients after a high-dose chemotherapy and autologous or allogeneic bone marrow transplantation. This required a review of issues related to the selection of patients for blood stem cell transplantation (HSCT), the development of new preventive and therapeutic tactics aimed at treating infectious and immunological complications in patients of this category, depending on the nature and status of the underlying disease and the timing of treatment.

Aim. To assess the severity, most typical complications and course of COVID-19 in patients during early and late posttransplant periods.

Materials and methods. We analyzed the data of patients after HSCT with active coronavirus infection hospitalized in the hematology department from 2020 to 2021. A total of 25 patients were hospitalized: 4 after allogeneic transplantation, 21 after autologous transplantation. According to the timing of HSCT, patients were divided into 2 groups: early period (ETP) (2-90 days after HSCT) - 14 patients, late period (LTP) (3-24 months after HSCT) - 11 patients.

Results. Severe coronavirus infection (grades III-IV according to computed tomography) was more often observed in patients in the ETP group (65 %) than in the LTP group (18 %). The incidence of respiratory failure was 70 and 36 % in the ETP and LTP groups, respectively. In the ETP group, agranulocytosis and the development of severe infectious complications (bacterial, fungal and viral) were observed significantly more often than in the LTP group, which required the appointment of reserve groups antibacterial therapy and antifungal therapy. Mortality in the ETP group was 35 %, while no deaths were recorded in the LTP group. The median duration of hospitalization for patients in the ETP and LTP groups was 20 and 13 days, respectively.

Conclusion. Patients early after HSCT are at higher risk of developing lower respiratory tract infections, are more likely to require hospitalization in the intensive care unit, and have a greater risk of death from COVID-19. Therapy with genetically engineered biological drugs is not contraindicated in the case of leukopenia and agranulocytosis in this group of patients.