Final height of Japanese patients with X-linked hypophosphatemic rickets: Effect of vitamin D and phosphate therapy

X-linked hypophosphatemic rickets (XLH) is one of the most common causes of rickets in infancy and childhood. Combination therapy of vitamin D and pho sphate is generally used for patients with XLH. Effect of treatment of vita min D and phosphate during childhood on final height of XLH has to be eluci dated in Japanese. There have been only three Caucasian studies on final he ight of XLH with treatment since childhood. Purpose of this study is to rep ort adult height and therapeutic effect of 22 Japanese participants (5 male s, 17 females) with XLH who were treated with phosphate (33-200 mg/kg/day a s phosphorus divided into 3 or 4 doses) and vitamin D (vitamin D-2 or 1 alp ha-hydroxyvitamin D-3) for more than five years and evaluate effect of the treatment on the final height retrospectively. Final height (FHt) for all p articipants was -1.69+/-1.11 SD. FHt (-1.69+/-1.11 SD) was significantly hi gher than height at the initiation of treatment (-2.38+/-0.88 SD) for all p articipants (P < 0.01). In conclusion, combination therapy of vitamin D and phosphate improved final height of Japanese patients with XLH as is simila r to previous Caucasian studies.