Complement-Mediated Hemolytic Anemia Triggered by Adenovirus Infection in a Pediatric Patient

Paroxysmal cold hemoglobinuria (PCH) is a rare form of complement-mediated hemolytic anemia in children. It is typically triggered by viral infections and mediated by Donath-Landsteiner antibodies, which induce intravascular hemolysis upon cold exposure. We reviewed the clinical course, laboratory findings, and management of a pediatric adenovirus-associated PCH to highlight diagnostic and therapeutic considerations. The eight-year-old previously healthy, unimmunized female patient presented with acute hemolytic anemia following a febrile viral illness. She developed jaundice and severe anemia with reticulocytosis, hyperbilirubinemia, and elevated lactate dehydrogenase (LDH). The direct antiglobulin test (DAT) was positive for complement (C3) but negative for immunoglobulin G (IgG). Blood bank evaluation revealed a positive Donath-Landsteiner antibody, confirming PCH. Treatment included normothermia, intravenous methylprednisolone, intravenous immunoglobulin (IVIG), epoetin alfa, folic acid, and empiric azithromycin. The patient's clinical condition stabilized with gradual hematologic recovery and resolution of symptoms. This case identifies adenovirus as a potential trigger for PCH in children and emphasizes the importance of early recognition, laboratory confirmation, and supportive management.