The clinical presentation and biochemical features of stage I vitamin D-deficiency rickets (VDR) and pseudohypoparathyroidism (PHP) type II are quite similar. These 2 entities have therefore often been mistaken for one another. We report our experience with 2 cases of stage I VDR that were originally diagnosed as PHP type II. The report provides an insight into the pathophysiology of VDR and PHP and thus allows for better differentiation between the 2 disease entities. It has become essential for pediatricians to recognize VDR owing to its resurgence in developed countries.
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