Growth retardation in children with chronic renal failure

Growth retardation is a major obstacle to full rehabilitation of children w ith chronic renal failure (CRF), Several factors have been identified as co ntributors to impaired linear growth and they include protein and calorie m alnutrition, metabolic acidosis, growth hormone resistance, anemia, and ren al osteodystrophy, Although therapeutic interventions such as the use of re combinant human growth hormone, recombinant human erythropoietin, and calci triol have made substantial contributions, the optimal therapeutic strategy remains to be defined. Indeed, growth failure persists in a substantial pr oportion of children with renal failure and those treated with maintenance dialysis, In addition, the increasing prevalence of adynamic lesions of ren al osteodystrophy and its effect on growth have raised concern about the co ntinued generalized use of calcitriol in children with CRF, Recent studies have shown the critical roles of parathyroid hormone-related protein (PTHrP ) and the PTH/PTHrP receptor in the regulation of endochondral bone formati on, The PTH/PTHrP receptor mRNA expression has been shown to he down-regula ted in kidney and growth plate cartilage of animals with renal failure. Dif ferences in the severity of secondary hyperparathyroidism influence not onl y growth plate morphology but also the expression of selected markers of ch ondrocyte proliferation and differentiation in these animals. Such findings suggest potential molecular mechanisms by which cartilage and bone develop ment may be disrupted in children with CRF, thereby contributing to diminis hed linear growth.