S5547 Severe Anemia in Cirrhosis Unmasked: A Case of Linezolid-Induced PRCA

Introduction: Pure red blood cell aplasia (PRCA) is a rare cause of anemia characterized by normocytosis, reticulocytopenia, and isolated absence of erythroid precursors in the bone marrow. While most cases are associated with autoimmune conditions, infections or malignancy, certain medications such as linezolid have been reported to cause PRCA. Although uncommon, linezolid-induced PRCA should be considered in patients presenting with severe anemia and low reticulocyte counts, particularly when other cell lines are relatively preserved. Our case underscores the importance of a broad differential in evaluating anemia, especially in patients with comorbidities such as cirrhosis that may mask rarer causes. Case Description/Methods: A 28-year-old woman with a history of severe alcoholic hepatitis, likely alcohol-associated decompensated cirrhosis, and chronic thrombocytopenia presented with progressive abdominal pain and distention; she additionally reported dizziness, lightheadedness, and watery stools with scant bright red blood. Labs revealed profound anemia (Hb 1.6), low reticulocyte count (0.1), normal LDH and elevated lactate (13). A right upper quadrant ultrasound showed fibrofatty parenchymal liver disease/cirrhosis, however the patient declined a liver biopsy to confirm the diagnosis. Hematology service was consulted and determined anemia was likely due to PRCA from recent linezolid use for MRSA bacteremia. She received 6 PRBC units with Hb improvement. Her course was complicated by COVID-19 with minimal symptoms. Paracentesis of an ascites pocket drained 6.8 L of fluid and was negative for SBP. She was discharged in stable condition to a shelter with follow-up care. Discussion: We present a patient with alcoholic liver disease who developed severe anemia, ultimately diagnosed as linezolid-induced PRCA. Linezolid-induced PRCA may often be overlooked in patients with cirrhosis or malignancy, both of which are commonly associated with anemia. Our patient, despite a history of alcoholic hepatitis and chronic thrombocytopenia, had a marked drop in hemoglobin that improved following linezolid cessation and transfusions. Bone marrow findings confirmed decreased erythropoiesis with normal platelet morphology and a low reticulocyte count, consistent with PRCA. Our case emphasizes the need to consider linezolid-induced PRCA in the differential diagnosis of anemia, particularly when typical causes do not fully explain the severity. Early recognition can prevent unnecessary interventions, as cessation of the drug often leads to recovery.