Internal Medicine and Medical Investigation Journal

Abstract

Author(s): Ehsan Arjmandzadeh, Azam Ghanei, Mohammad Bagher Owlia, Sara Talebi

Vitamin D (Vit D) is a prohormone that can be activated during a sequential hydroxylation done by two major mitochondrial cytochrome P450 liver and renal enzymes. Vit D-dependent rickets type 1 (VDDR1) is a rare autosomal recessive hereditary disorder resulting from defective renal 1α-OHase presenting with severe rickets, hypocalcemia, and secondary hyperparathyroidism. Although homozygous Vit D hydroxylation deficient patients develop severe rickets symptom and signs before the age of 12 months, heterozygous types have minor symptoms and are extremely rare presenting as late as 14 years after birthday. Here we present a suspicious case of VDDR1 at 21 years old of age with mild symptoms and signs.