Hyperhemolysis in the Setting of Mixed-Autoimmune Hemolytic Anemia: A Rare Complication of COVID-19.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a novel human pathogen known for its predilection on the respiratory system. Herein, we present a unique case in which a patient developed hyperhemolysis in the setting of mixed autoimmune hemolytic anemia (AIHA) secondary to SARS-CoV-2. A 33-years-old male with a past medical history of resolved immune thrombocytopenic purpura (ITP) presented to the hospital with symptoms of jaundice after being infected with SARS-CoV-2. On admission, his Hgb was 12.5 g/dL. Lab results showed indirect bilirubin of 13 mg/dL, LDH at 759 U/L, haptoglobin <10, and the percent reticulocyte count was 2.33%. A direct antiglobulin test (DAT) was also positive for C3, IgG, anti-E, in addition to both warm and cold autoantibodies. PCR was positive for COVID-19. Within two days of admission, his Hgb dropped to 5.9 g/dL. A total of seven units of packed red blood cell (pRBC) was required to achieve a Hgb of 6 g/dL in 48 hours. Patients with preexisting hematological abnormalities have a propensity to develop AIHA in the setting of the virus. The majority of the cases described in the literature were associated with warm AIHA. Our patient tested positive for both warm and cold antibodies, which may partially explain the mechanism behind hyperhemolysis in our patient.