Thrombotic thrombocytopenic purpura secondary to ABO group incompatible blood transfusion in a patient after cardiac surgery
A 64-year-old male patient developed nausea, vomiting and chills during red blood cell (RBC) suspension transfusion on the second day of coronary by-pass surgery. Transfusion was stopped immediately. Caring physicians recognized an error in labeling of the RBC suspension. With a preliminary diagnosis of ABO incompatible transfusion reaction, aggressive hydration was instituted. In the follow-up, hemoglobin values dropped and lactate dehydrogenase (LDH) and serum creatinine levels started to increase proportionally. Urine color was darkened with a gradual development of oligo-anuria and acute kidney injury (AKI). On the 7th day of transfusion, platelet count decreased and LDH level increased significantly. In peripheral blood smear, polychromasia and abundant schistocytes were seen. TTP was diagnosed according to following criteria: Thrombocytopenia, microangiopathic anemia, increase in LDH level, and development of AKI. We started hemodialysis and plasmapheresis on the 8th day because of TTP and AKI. After 11 and 15 sessions of hemodialysis and plasmapheresis, respectively, platelet, LDH, urea, creatinine levels and urine output improved. Steroid therapy (1 mg/kg/day) was given simultaneously. The patient showed a dramatic improvement, and plasmapheresis and hemodialysis were stopped subsequently. On the 41th day of admission he had bloody diarrhea and C. Difficile toxin A was found to be positive in feces and vancomycin was administered for pseudo-membranous enterocolitis. On the 50th day, multiple infarctions were seen on cranial CT that was performed for the evaluation of confusion. Blood urea, creatinine and LDH levels increased, hemoglobin and platelet levels decreased again. In addition schistocytes were seen in blood smear. Plasmapheresis was performed because of recurrent thrombotic microangiopathy and hemodialysis was also started again. Thrombocytopenia persisted until the patient died eventually due to cardiac arrest. The pertinent laboratory data and major interventions are chronologically illustrated in [].