Passenger lymphocyte syndrome: a forgotten cause of postliver transplant jaundice and anemia.

A 48-year-old man with cirrhosis secondary to nonalcoholic steatohepatitis and chronic hepatitis C infection underwent a successful orthotopic liver transplant from a B+ donor without intraoperative complications. His postoperative course was complicated by hemolytic anemia, and he was ultimately diagnosed as having passenger lymphocyte syndrome. Passenger lymphocyte syndrome is a complication of both solid-organ and stem cell transplants. It is caused by donor B lymphocyte production of antibodies causing a primary or secondary immune response to recipient erythrocytes. Most commonly, it is in the setting of minor ABO mismatches, such as with a group B liver transplanted into a group AB recipient. Typically, passenger lymphocyte syndrome presents as a mild, self-limiting hemolytic anemia. Laboratory findings are consistent with other forms of hemolytic anemia including decreased hemoglobin and haptoglobin, elevated reticulocyte count, and indirect hyperbilirubinemia There is no definitive treatment for passenger lymphocyte syndrome or strong evidence to favor a particular treatment regimen. Passenger lymphocyte syndrome has been successfully treated with supportive care and blood transfusions matched to the liver donor. It is prudent that physicians caring for patients who receive ABO mismatched organs have a high index of clinical suspicion for passenger lymphocyte syndrome during the early postoperative period when posttransplant patients present with jaundice and anemia.