[83-year-old with angina pectoris, hemoglobinuria and icterus]

An 83-year-old female patient presented with angina pectoris, hemoglobinuria and jaundice. Laboratory diagnostics proved difficult due to hemolysis in all blood tubes, following re-evaluation after warming the blood sample.With low haptoglobin, elevated lactate dehydrogenase and elevated indirect bilirubin, we made a suspected diagnosis of autoimmune hemolytic anemia with cold antibodies, which was confirmed through a positive Coombs test and detection of C3d-loaded erythrocytes. Complications included NSTEMI type 2 in the context of hemolysis and acute kidney damage. A Proteus mirabilis bacteremia was diagnosed as the cause of the AIHA.After treatment of the underlying infection and high-dose prednisolone therapy, the hemolysis parameters regressed and the patient could be discharged to outpatient hematologic follow-up.Interdisciplinary and multi-professional collaboration with laboratory staff and transfusion medicine is crucial for both rapid diagnosis and further treatment. Blood transfusions in AIHA should only be carried out according to strict indications.