The Course of COVID-19 in a Patient with Aplastic Anemia and Paroxysmal Nocturnal Hemoglobinuria Clone: A Case Report and Literature Review

Introduction: Aplastic anemia (AA) and paroxysmal nocturnal hemoglobinuria (PNH) are bone marrow failure syndromes. A 20–40% of patients with AA have a PNH clone at diagnosis. To date, there are little data about the course of COVID-19 in patients with AA and PNH. Case Presentation: A 36-year-old gentleman, who was previously diagnosed as a case of AA with PNH clones off immune-suppressive therapy, presented with fever and cough and was diagnosed with mild pneumonia due to COVID-19 with positive nasopharyngeal swab polymerase chain reaction (PCR) for severe acute respiratory syndrome coronavirus 2. His clinical course was benign except transient thrombocytopenia. He was asymptomatic after day 4, and viral PCR was negative on day 21. Discussion: Though studies have shown that COVID-19 is associated with lymphopenia, our patient had a normal to high lymphocyte count. The neutrophil to lymphocyte ratio (NLR) was <1 during COVID-19, which correlates with the mild course of the disease. To know whether elevated lymphocyte count, low NLR, and benign course of COVID-19 is a standard feature for all patients with underlying AA, we need more case reports and series. The significance of this case report is that it describes the course of COVID-19 in a patient with AA and PNH clones and, up to our knowledge, is the first report showcasing the association between these rare combinations of diseases.