Aplastic anemia and COVID-19: how to break the vicious circuit?

Am J Blood Res 2020;10(4):60-67 www.AJBlood.us /ISSN:2160-1992/AJBR0115005 Original Article Aplastic anemia and COVID-19: how to break the vicious circuit? Safaa AA Khaled1, Ahmed A Hafez2 Department of Internal Medicine, Clinical Hematology Unit, Assiut University Hospital, Faculty of Medicine/ Unit of Bone Marrow Transplantation, South Egypt Cancer Institute, Faculty of Medicine, Assiut University, Egypt; 2 Department of Electrical Engineering, Faculty of Engineering, Assiut University, Egypt 1 Received May 26, 2020; Accepted August 17, 2020; Epub August 25, 2020; Published August 30, 2020 Abstract: Aplastic anemia (AA) is a type of anemia that is caused by an intrinsic defect of hematopoietic progenitors or an extrinsic immune mediated destruction of stem cells. Patients commonly presented with pancytopenia, particularly leukopenia that renders patient susceptible to various infections. COVID-19 is one of these infections that could be life threatening and highly contagious. Infection with COVID-19 is expected in a patient who developed fever, respiratory manifestations, leukopenia and lymphopenia together with history suggestive of exposure to infection. Furthermore COVID-19 was found associated with thrombocytopenia, agranulocytosis and monocytopenia in severe cases. Thus the relationship between COVID-19 infection and AA would be a vicious circle as both cause leukopenia and lymphopenia. This study aimed to break this circle, through proposing risk stratification of vulnerability to COVID-19 in AA patients who were admitted in our institution in the period from Mar. 2018 to Mar. 2020 followed by a strict preventive plan tailored for each risk group. 79% of AA patients were at high risk of acquiring COVID-19 infection if exposed. This group of patients have to be targeted with more aggressive preventive plan than normal healthy persons. In conclusion this study proposed next step in combating COVID-19 infection through mass survey of high risk people then application of specific precautions to them, perhaps they could be candidate for future vaccine or prophylactic treatment. Keywords: Aplastic anemia, COVID-19, vicious circle Introduction AA is a rare and heterogeneous disorder. It is defined as pancytopenia with a hypocellular bone marrow in the absence of an abnormal infiltrates, marrow fibrosis or dysplastic changes. To diagnose AA a hematologist must exclude other causes of pancytopenia [1-3]. The majority (70-80%) of AA cases are idiopathic [1-3]. The incidence of AA is 2-3 per million per year in Europe, but higher in East Asia. There is a biphasic distribution of AA, with peaks at 10-25 years and over 60 years [4]. The recent COVID-19 epidemic is dated back to December 2019, where case#0 was reported in Wuhan, China. Although the symptoms of COVID-19 often resemble those of influenza, including fever and cough, COVID-19 appears to be far more contagious than the flu and it has a fatality rate 10 times higher than that of influenza. The crude case fatality rate, based solely on reported numbers of cases and deaths, appears to be 3.96%, the actual risk of death from COVID-19 is unclear because the testing and supportive care for SARS-CoV-2 infection vary widely across the world. Actual death rates vary enormously, from 7.3% in Italy to 0.9% in South Korea. Until now, the reasons for these wide disparities in fatality rates are properly unidentified. Age, > 70 years, underlying medical conditions such as hypertension, cardiovascular and pulmonary diseases are candidate reasons for this escalating fatality rate. Conversely, in contrast to the H1N1 swine flu epidemic of 2009, rates of symptomatic COVID-19 infection and serious illness among children and adolescents are significantly lower than for older adults [5-8]. Global enormous efforts are directed to discover an effective vaccine for COVID-19. However, Aplastic anemia and COVID-19 a provisional vaccine is still undeveloped yet. Traditional measures for epidemic control of respiratory illness such as influenza could function for COVID-19. These measures include social distancing, frequent hand washing, and avoiding touching one’s eyes, nose, or mouth. A self-quarantine up to 14 days is obligatory for persons contacted with COVID-19 patient. These measures have resulted in partially positive results in attenuating the infection and hence the fatality rate of COVID-19 infection. The average incubation period of COVID-19 is 5-7 days, but some cases have experienced longer incubation periods up to 12-14 days after exposure [9]. AA patients have high potential risk of attracting COVID-19 infection due to: ● The nature of the disease with leukopenia and pancytopenia, with lowered immunity. ● The follow up schedule of the patient, which entails regular visits to tertiary hospital. These health facilities may be faraway requiring patient travel, which is via crowded public transport means, particularly in developed countries and rural areas. ● Finally, the main treatment for AA is hematopoietic stem cell transplantation (HSCT), immunosuppressive therapy (IST) and thrombomimetics (Eltrombopag), in severe cases, all render patient immunocompromised. The COVID-19 infection was found to be complicated with anemia, lymphopenia, neutrophilia, agranulocytosis, monocytopenia and atypical reactive lymphocytes, particularly in severe cases [10]. Accordingly the relationship between COVID-19 and AA would be a vicious circle. AA exerts a social and economic burden on both patients and communities as a recent study in Egypt revealed [11]. Thus, AA patients have to follow even more restrictive measures than ordinary candidates for combating COVID19 infection. This was the main motive for this study. The objectives of this study were: 1. Identifying statistically the high risk groups of acquiring COVID-19 infection among AA patients. 61 2. Proposing specific preventive measures of COVID-19 infection tailored for each risk group. Subjects and methods Patients and settings AA patients (idiopathic and secondary), diagnosed/admitted at the Clinical Hematology Unit of Internal Medicine Department, Assiut University Hospital, in the period from Mar. 2018 to Mar. 2020, were retrospectively enrolled in the study. This group of patients is on regular follow up at the outpatient clinic according to their treatment plan. Furthermore they usually reported to the emergency department for blood transfusions and other life critical medical services. Patients with inherited bone marrow failure syndrome were excluded from the study. Data collection and patient categorization Demographic, medical history, clinical, and the last hematologic data of the study patients were collected from their hospital records. Data concerning treatment plan and frequency of admission per year were also recorded. Diagnosis of AA and assessment of disease severity were carried out according to the modified Cammita criteria as following: 1) Very Severe AA (V (...truncated)