THE DISCIPLINE OF pediatric nephrology is unique and challenging because it encompasses the widest developmental stages of life, from in utero presentation of chronic kidney disease (CKD) through kidney failure presenting in early adulthood. CKD in our patients may arise from embryological disturbances, genetic mutations, acquired glomerulopathies and/or tubulopathies, systemic metabolic diseases, immune-mediated diseases, or those diseases that derive—in part—from lifestyle choices. The natural history of many of these diseases is being rewritten continually, as longevity for patients increases beyond that seen by our mentors before us. We see the influence of socio-demographic distributions on disease expression and severity, and the insufficiencies of organ availability for transplantation on disease chronicity.
In the pediatric population, body calcium balance remains markedly positive to support both somatic growth and bone mineral accretion. The sine qua non of pediatric CKD is the marked change in these two processes that leads to the devastating clinical disease that we term “osteodystrophy.” We have come to realize that the disorder encompasses marked disturbances in mineral homeostasis with chronic metabolic acidosis, secondary hyperparathyroidism (2° HPT), insufficiency of 1,25-dihydroxyvitamin D, and failure of linear growth in addition to extraskeletal disease. Thus, we have seen children, adolescents, and young adults with an as yet undefined cardiovascular disease associated with calcium in incorrect places within the vasculature, similar to that seen in adult patients who develop CKD de novo. We recognize the pervasive nature of CKD, and perhaps a more subtle manifestation of its osteodystrophy, in abnormal neurological development of our youngest patients.
Although we were members of the committee for the preparation and publication of the National Kidney Foundation KDOQI Guidelines for bone metabolism and disease in CKD in adults, we recognized that the subject in that population was filled with enough controversy that recommendations for children could not properly be placed within it. Therefore, the leaders of the KDOQI process acceded to our request for a meeting in Chicago, in October 2002, to begin the arduous process of sorting through the literature to produce a pediatric-specific set of KDOQI guidelines for bone metabolism and disease in CKD with our colleagues and committee members.
The task differed initially from the resultant guidelines seen here; but with very limited resources, and no external review of extant literature by a third party, we decided late in 2003 to follow the structure of the adult-based bone metabolism and disease guidelines instead. We owe great thanks to that group for their wisdom in allowing us to use some of their work, and adapt it where indicated for the aspects unique to pediatric osteodystrophy. It became rather clear, quickly, that the area of osteodystrophy in pediatric CKD is highly uninvestigated, and is a wonderful career-building opportunity for the generation of pediatric nephrologists who will follow the members of this writing committee.
As Co-Chairs, we owe a deep gratitude to our committee members. Each worked long hours, acceded to our many requests on short notice with a 'can-do' attitude, and worked in a collegial manner that allowed the project to succeed in a lofty manner.
With the successful completion of our task, we need to thank many of our colleagues who did not serve on the committee, but who taught us much from their science, and from their empathetic care of patients. We hope we acknowledged, by attribution within our text, their work and toil, and we take responsibility for any mistakes of omission in this regard. We thank the entire staff of the National Kidney Foundation for their excellent support, and especially that of Mr. Anthony Gucciardo and Ms. Donna Fingerhut, who were tireless in their pursuit of our goals. Drs. Gary Eknoyan and Adeera Levin are to be commended for their spiritual input to our project (and ourselves) during its long course.
As you, the Reader, use these guidelines, you will be quick to see its flaws and weaknesses, as all such guidelines possess. We welcome your input directly through the National Kidney Foundation to those areas that need improvement, emendation, or removal in subsequent iterations of the work. Despite this caveat, we believe that regular attention to our patients' osteodystrophy in a manner proscribed within the guidelines will lead to an improved outcome in every facet of the disease.
Craig B. Langman, MD
Work Group Co-Chair
Isidro B. Salusky, MD
Work Group Co-Chair