Hematopoietic progenitor cell transplantation from a donor with indeterminate human immunodeficiency virus antibody status

Abstract

A 53-year-old woman with acute myeloid leukemia achieved remission after two courses of induction chemotherapy. Allogeneic hematopoietic progenitor cell transplantation (HPCT) was planned. HLA typing of three siblings identified a 49-year-old fully matched sister. The potential donor’s test result for human immunodeficiency virus (HIV-1 and -2) antibody, however, was “indeterminate” by two commercial kits (VIDAS HIV DUO, bioMerieux, France, which detects antibodies against gp41, gp36, subtype group O, and p24 antigen; and AxSYM HIV-1/-2 assay, Abbott Laboratories, Wiesbaden, Germany, which detects antibodies against HIV-group M envelope, HIV-group O envelope, HIV-core, and HIV-2 envelope), as well as by Western blot (HIV blot 2.2 Western blot assay, Genelabs Diagnostics, Singapore). The same results were obtained when repeated after 4 and 8 months. Neither the potential donor nor her spouse had high-risk HIV exposures. Her physical examination and laboratory screening, including lymphocyte count, were normal. Results for HIV RNA reverse transcription-polymerase chain reaction (PCR, Amplicor HIV-1 Monitor, Version 1.5, Roche Diagnostics, Branchburg, NJ), as well as for HIV proviral DNA PCR (LabCorp, Burlington, NC), were negative. With informed consent, a myeloablative marrow transplantation was performed, and the patient engrafted on Day 26. After 6 months’ follow-up, the recipient’s HIV antibody test results were negative whereas the donor’s remained indeterminate. We believe that this is the first report of an HPCT using a donor with an indeterminate test result for HIV antibody. Indeterminate HIV antibody status can have many causes, including interfering antibodies from autoimmune diseases, transfusion, pregnancy, or animal exposure. Typically, these results are transient and the samples seroconvert to negative with time. Not all indeterminate HIV antibody results will seroconvert to negative, however. Low-level viremia 1 and viral clearance may be associated with HIV antibody‐indeterminate results and, reportedly, 0.4 to 7.3 percent of these cases convert to HIV seropositivity. 1-3