title: Hemolytic anemia due to passenger lymphocyte syndrome in solid malignancy patients treated with allogeneic natural killer cell products.
abstract: BACKGROUND
  Allogeneic natural killer (NK) cell products for treatment of solid organ malignancies were prepared by performing T (CD3+)-cell depletion on nonmobilized apheresis mononuclear cell collections. The products were not B-cell depleted. This report details two cases of passenger lymphocyte syndrome (PLS) after NK-cell infusion.
  
  
  METHODS
  Patient 1 is a blood group A+ 56-year-old female with Stage IV ovarian carcinoma who received NK cells from an O+ donor. On day +7 she developed new hemolytic anemia. Direct antiglobulin test (DAT) was positive for immunoglobulin G and C3, and the eluate contained anti-A. Subsequently, anti-A was identified on reverse typing. She was transfused with group O red blood cells (RBCs). By day +12 she forward typed as O with anti-A and B on reverse typing. By day +42, DAT was negative with only weak anti-A on reverse typing. Patient 2 is a blood group B+ 51-year-old female with metastatic lobular breast carcinoma who received NK cells from an O+ donor. On day +7 she developed new hemolytic anemia. DAT was positive, and the eluate contained anti-A and -B. Anti-A reactivity was due to anti-A,B. The next day she developed new anti-B on reverse typing. She was transfused with O RBCs. Anti-B titer increased to a maximum of 512 on day +12. At discharge on Day +29 her anti-B titer was still 32.
  
  
  CONCLUSIONS
  These patients developed PLS after infusion of NK cells. Because of these cases NK-cell products are now B (CD19+)-cell depleted at our institution, and this approach is recommended for other centers.
authors.affiliation: Canadian Blood Services, Central Ontario, Toronto, Canada.
authors.forename: Robert
authors.initials: R
authors.lastname: Skeate
authors.forename: Charanjeet
authors.initials: C
authors.lastname: Singh
authors.forename: Sarah
authors.initials: S
authors.lastname: Cooley
authors.forename: Melissa
authors.initials: M
authors.lastname: Geller
authors.forename: Joan
authors.initials: J
authors.lastname: Northouse
authors.forename: Julie
authors.initials: J
authors.lastname: Welbig
authors.forename: Arne
authors.initials: A
authors.lastname: Slungaard
authors.forename: Jeff
authors.initials: J
authors.lastname: Miller
authors.forename: David
authors.initials: D
authors.lastname: McKenna
mesh_terms: D000743:Anemia, Hemolytic / Q000175:diagnosis / Q000209:etiology*; D000744:Anemia, Hemolytic, Autoimmune / Q000150:complications / Q000175:diagnosis; D001327:Autoimmune Diseases / Q000150:complications* / Q000175:diagnosis; D005260:Female; D006801:Humans; D016219:Immunotherapy, Adoptive / Q000009:adverse effects*; D007694:Killer Cells, Natural / Q000276:immunology / Q000637:transplantation*; D008214:Lymphocytes / Q000276:immunology; D008875:Middle Aged; D009369:Neoplasms / Q000276:immunology / Q000628:therapy*; D013577:Syndrome; D014184:Transplantation, Homologous