title: A rare, potentially life-threatening presentation of passenger lymphocyte syndrome.
abstract: BACKGROUND
  Passenger lymphocyte syndrome occurs when donor lymphocytes are transplanted with a solid organ and produce alloantibodies that react with antigens on the recipient's red blood cells (RBCs). Typically, passenger lymphocyte syndrome presents as immunoglobulin G antibody-mediated, extravascular hemolytic anemia with reticulocytosis. Often, the donor was alloimmunized before transplantation.
  
  
  METHODS
  A 34-year-old Group O, D+ man with a negative antibody screen received a liver transplant from a Group O, D- donor. Twenty Group O, D+ RBC units were transfused on Postoperative Days (PODs) 0 through 2. On POD 7, the patient developed anemia, a weakly positive antibody screen, and a positive direct antiglobulin test with anti-D in the eluate. After POD 8, a D- transfusion protocol was initiated. Despite laboratory evidence of hemolysis, two initial peripheral blood smears showed no increase in schistocytes or spherocytes, the reticulocyte count was depressed, and a marrow biopsy revealed erythroid hyperplasia. Eventually, anemia resolved after a period of medication non-compliance; however, a positive direct antiglobulin test persisted to the last follow-up date (POD 233).
  
  
  RESULTS
  Other potential causes of aplastic anemia were investigated, but no alternative cause was found. History excluded passive anti-D. D+, LW- cells were reactive, excluding anti-LW. Genotyping showed no evidence of a partial D genotype. Chart review revealed that the liver donor had a history of anti-D. A diagnosis of passenger lymphocyte syndrome was reached.
  
  
  CONCLUSIONS
  Although antibody-mediated hemolytic anemia has been reported to cause reticulocytopenia in the presence of marrow erythroid hyperplasia, this report of passenger lymphocyte syndrome causing a similar post-transplant anemia in association with reticulocytopenia is noteworthy.
authors.affiliation: Department of Laboratory Medicine and Pathology, University of Minnesota, Minneapolis, Minnesota.
authors.forename: Thomas J
authors.initials: TJ
authors.lastname: Gniadek
authors.affiliation: Department of Pathology and Laboratory Medicine, Wing-Kwai and Alice Lee-Tsing Chung Transfusion Service, David Geffen School of Medicine at the University of California-Los Angeles, Los Angeles, California.
authors.forename: Andrea M
authors.initials: AM
authors.lastname: McGonigle
authors.affiliation: Department of Pathology, Division of Transfusion Medicine, Johns Hopkins Hospital, Baltimore, Maryland.
authors.forename: R Sue
authors.initials: RS
authors.lastname: Shirey
authors.affiliation: Department of Pathology, Division of Transfusion Medicine, Johns Hopkins Hospital, Baltimore, Maryland.|American Red Cross, Greater Chesapeake & Potomac Region, Baltimore, Maryland.
authors.forename: Patricia A
authors.initials: PA
authors.lastname: Brunker
authors.affiliation: Department of Medicine, Division of Hematology, Johns Hopkins University School of Medicine, Baltimore, Maryland.
authors.forename: Michael
authors.initials: M
authors.lastname: Streiff
authors.affiliation: Department of Surgery, Division of Transplantation, Johns Hopkins Hospital, Baltimore, Maryland.
authors.forename: Benjamin
authors.initials: B
authors.lastname: Philosophe
authors.affiliation: Department of Pathology, Division of Transfusion Medicine, Johns Hopkins Hospital, Baltimore, Maryland.
authors.forename: Evan M
authors.initials: EM
authors.lastname: Bloch
authors.affiliation: Department of Pathology, Division of Transfusion Medicine, Johns Hopkins Hospital, Baltimore, Maryland.
authors.forename: Paul M
authors.initials: PM
authors.lastname: Ness
authors.affiliation: Department of Pathology, Division of Transfusion Medicine, Johns Hopkins Hospital, Baltimore, Maryland.
authors.forename: Karen E
authors.initials: KE
authors.lastname: King
mesh_terms: D000017:ABO Blood-Group System; D000328:Adult; D000743:Anemia, Hemolytic / Q000209:etiology*; D001787:Blood Group Incompatibility / Q000276:immunology*; D006801:Humans; D016031:Liver Transplantation / Q000009:adverse effects*; D008214:Lymphocytes / Q000276:immunology*; D008297:Male; D017701:Reticulocyte Count; D012204:Rh-Hr Blood-Group System / Q000276:immunology; D018029:Rho(D) Immune Globulin / Q000276:immunology; D014019:Tissue Donors
chemical_list: D000017:ABO Blood-Group System; C061961:RHO(D) antibody; D012204:Rh-Hr Blood-Group System; D018029:Rho(D) Immune Globulin