Autopsy findings in umbilical cord blood transplant recipients.

Human umbilical cord blood stem cells have been used to reconstitute hematopoiesis in patients with malignant and nonmalignant diseases. The immunologic immaturity of cord blood cells confers peculiar characteristics to these hematopoietic precursors. Autopsy reports from January 1, 1988, through June 30, 1998, were searched for patients who had received an umbilical cord blood transplant (UCBT). Thirty-two patients (19 male, 13 female) were identified with a mean age at autopsy of 13.0 years with a range from 1 to 52 years. Most patients (24) underwent UCBT for treatment of a malignant neoplasm, while the remainder were treated for immunodeficiencies (4), Lesch-Nyhan syndrome (2), Hurler syndrome (1), and Diamond-Blackfan syndrome (1). Sixteen patients had at least 1 infectious complication, and 8 patients had multiple infections. Organisms included mycoses (7 patients), viruses (8 patients), bacteria (3 patients), and Toxoplasma (2 patients). Hemorrhagic complications, such as intra-alveolar hemorrhage and gastrointestinal tract hemorrhage, were found in 24 patients. Other frequent findings at autopsy included diffuse alveolar damage (15 patients), hepatic veno-occlusive disease (11 patients), and acute or chronic graft-vs-host disease (9 patients). Patients who have received UCBT represent a unique population of immunosuppressed patients. Infectious and hemorrhagic complications frequently are encountered at autopsy, and pathologists performing autopsies on these patients should be alert to unusual pathogens.