ABSTRACT
I) RISK FOR INFECTION BMT patients are susceptible to infections from neutropenia, depressed T and
B cell function, disruption of anatomical barriers (mucositis, indwelling intrave nous and urinary catheters) and immunosuppressive medications (steroids, cy closporine, methotrexate, anti-thymocyte globulin). Susceptibility to infection also depends on the type of BMT. A) Neutropenia
Risk of infection in neutropenic patients increases with depth of absolute neutrophil count (ANC) nadir (especially if < 100/pl), rapid rate of ANC de cline and protracted duration of granulocytopenia (> 10 days). All of which are anticipated complications of BMT. The expected duration of neutropenia after hematopoietic stem cell transplantation (HSCT) depends on prior treat ment, use of growth factors and source of hematopoietic stem cells (i.e. pe ripheral blood or bone marrow). The mean duration of an ANC less than 500/pl after bone marrow HSCT (autologous, conventional allogeneic and T cell de pleted allogeneic BMT) is 2 to 3 weeks. The mean duration of an ANC less than 500/pl is shorter after peripheral blood HSCT (10-14 days). However, in gen eral, neutropenia is protracted for autologous HSCT regardless of source (pe ripheral blood or marrow) if the patient is heavily pretreated with prior che motherapy or the hematopoietic cells are manipulated ex vivo (e.g. chemical purging). Allograft failure is likely if the ANC remains less than 100/pl after day 21.
