Hematopoietic growth factors in prophylaxis and therapy of infections complications in children with neutropenia

Hematopoietic colony-stimulating factors have been introduced into clinical practice as additional supportive measures to reduce infectious complications associated with congenital or acquired neutropenia. Over the past decade, we have begun to appreciate the subtler aspects of the proper use of G-CSF and GM-CSF, identifying appropriate indications and contraindications. In the course of evaluating the corpus of studies, a set of formal recommendations have been propagated for the judicious use of these expensive growth factors [3,4,152,174]. To prevent serious infection, the use of G-CSF or GM-CSF is recommended in a subset of pediatric cancer patients shortly after having received chemotherapy or a form of a marrow transplant. Children with highly intensive chemotherapy (e.g., children with high risk ALL or NHL) seem to benefit from hematopoietic growth factors whereas this is still unclear for children undergoing therapy for solid tumors. An exciting development is the use of G-CSF and GM-CSF to mobilize peripheral-blood progenitor cells for autologous or allogeneic transplantation. In pediatric patients with hematological diseases, there are only few data on the use of hematopoietic growth factors in children with myelodysplastic syndrome. Experts recommend the early administration of G-CSF in children with very severe aplastic anemia. The use of G-CSF is also recommended in children with severe chronic neutropenia, but these patients have to be monitored regularly for cytogenetic abnormalities. No larger study has shown a clinical benefit of hematopoietic growth factor in preterm or term infants. Future studies in pediatric patients are clearly warranted to address several issues. Prospective clinical trials are still needed to define specific treatment groups who can benefit from growth factor support. in this regard, efforts must be directed at better defining the endpoints and in particular assigning value to reduction in treatment of possible infectious complications, such as days in hospital, antibiotic usage and costs. In addition, randomized studies are required to evaluate the proper dosage and duration of therapy, which most likely will vary between groups of patients. In addition, combinations of different growth factors have to be tested, particularly if ex vivo expansion and the storage of hematopoietic stem cells are to be utilized in a wider spectrum of patients.