[Delayed Hemolytic Transfusion Reaction after Mitral Valve Replacement:Report of a Case]

We report a case of delayed hemolytic transfusion reaction (DHTR) after mitral valve replacement (MVR). A 67-year-old woman with a history of blood transfusion( BT) was admitted for MVR. Preoperative laboratory test proved to be negative for irregular antibodies except anti-Dia. She underwent MVR using a mechanical prosthesis and compatible blood products were transfused perioperatively. On post-operative day 13, she developed hemoglobinuria and anemia with elevated serum total bilirubin and lactic dehydrogenase levels. Transesophageal echocardiography showed trivial transvalvular leakage. Laboratory test successfuly identified another irregular antibody, anti-Jkb antibody. The patient had Jkb negative BT and did not need re-operation. Later, she recovered with no signs of hemolysis. Since anti-Jkb antibody gets undetectable within a few months, it is difficult to find out before surgery. As hemolysis following cardiac surgery is more commonly associated with prostheses and extracorporeal circulation than DHTR. Physicians should, however, be aware of this unusual complication especially in patients who underwent BT.