vitamin D-dependent rickets(redirected from pseudovitamin D resistant rickets)
vitamin D-dependent ricketsAn autosomal recessive disorder of bone and calcium metabolism characterised by the signs and symptoms of rickets (hypocalcaemia, low-to-normal plasma phosphate and increased parathyroid hormone).
Vitamin D-dependent rickets, types
▪ Type I—Characterised by defective 25-hydroxy-cholecalciferol 1-α-hydroxylase, which converts 25-(OH)- to 1,25-(OH)2 vitamin D; it responds to vitamin 1,25-(OH)2D3.
▪ Type II—Characterised by alopecia and high plasma levels of vitamin 1,25-(OH)2D3 due to end-organ defects of renal tubules, intestinal mucosa and bone; it is refractory to therapy.