Preface

For many decades, the subspecialties of pediatric hematology and pediatric oncology have been practiced by the same individuals. Today in many institutions this still occurs, either because the size of the institution does not allow the recruitment of sufficient pediatric hematologists and oncologists to allow for separate services, or because the practitioners themselves, trained in a combined hematology/oncology program, are disinclined to give up part of what they trained to do. Other institutions with sufficient interest and resources, including ours, have come to the realization that the knowledge base and experience to function optimally as a pediatric hematologist or oncologist mandate a separation in the same manner as the care for children requiring stem cell transplantation is now relegated primarily to pediatric bone marrow transplantation physicians. The formal separation of pediatric hematology and oncology allows specialists to focus on specific hematologic disorders such as sickle cell disease, transfusion medicine, or clotting disorders, to study their pathophysiology in detail, to establish collaborative research studies to optimize treatment, and to develop novel therapeutic approaches. We believe that a focused approach is required to further develop this exciting field of medicine. This issue of Pediatric Clinics of North America affirms the fact that pediatric hematology has evolved in a multifaceted and often complex specialty on its own. For example, managing patients with hemophilia who have inhibitors is not always easy, whereas optimally treating the increased number of young patients who develop a venous thromboembolism requires specialized expertise and experience, and really requires the involvement of a knowledgeable specialist.

Unlike pediatric oncology, where most treatments are directed or have been established by prospective randomized clinical trials, the management of many primary hematologic conditions in children lacks such guidance. For some conditions, most notably sickle cell disease and, more recently, disorders of hemostasis, the lack of insight gained through prospective clinical trials is currently being addressed, but for other hematologic conditions, some of which are very rare, pediatric hematologists need to determine management based on a review of the literature and experience. Assessing the value of publications is not always a trivial matter and we have therefore included an article that specifically deals with making management decisions when so-called “solid” information is unavailable.

The articles selected for this issue of Pediatric Clinics of North America cover aspects that most pediatricians deal with on a regular basis (eg, immune thrombocytopenic purpura [ITP], vascular malformations, and transfusions), but which continue to pose challenges with regard to optimal management. Other articles deal with hematologic disorders in children who most often are managed by pediatric hematologists for their hematological condition (eg, stroke, thalassemia, hereditary spherocytosis, and sickle cell disease), but are also followed by pediatricians or general practitioners for overall health care management. In either case, the authors contributing to this issue have done an excellent job in providing a relevant update on hematologic disorders that affect many children worldwide.

As some authors indicate, we anticipate that the future of pediatric hematology will include a better understanding of the biology that leads to hematologic diseases as well as interdisciplinary multi-institutional (and, on occasion, international) trials to further improve life expectancy and/or quality of life of children affected by these hematologic disorders.