Febrile neutropenia in allogeneic transplantation

Infections post allogeneic bone marrow transplant (BMT) are a major problem. Post BMT, three periods with infectious complications are discerned: pre-engraftment and early recovery, mid recovery and late recovery. In the first period mucosal damage and neutropenia are the major host defence deficits. Bacterial infections with Gram-positive and Gram-negative organisms, and fungal infections are seen in this period. In the mid recovery phase graft versus host and its treatment contribute to diminished host defences. Viral infections and fungal infections predominate. In the late recovery phase chronic graft versus host reaction impairs the monocyte macrophage function and CD4 counts are low. In this phase patients are at risk for infections with encapsulated bacteria, fungi, Pneumocystis carinii and Toxoplasma. Strategies for the management of febrile neutropenia are similar to those in 'high risk' neutropenic patients: immediate broad spectrum I.V. antibiotics (3rd or 4th generation cephalosporin+/-aminoglycoside or carbapenem) and early amphothericin B (lipid formulation) if fever persists beyond 5 days despite adequate I.V. antibiotics. Cytomegalovirus (CMV) prophylaxis or better preemptive therapy guided by viraemia is accepted practice. Prevention of infection measures, antimicrobial, antifungal and viral prophylaxis are generally accepted strategies but would differ from center to center. The post transplant infection history will change with different transplant techniques and evolving prophylactic and preemptive treatments.