TLDR Some people have genetic mutations that make them resistant to vitamin D, leading to rickets even with enough vitamin D intake.
The document discussed tissue resistance to vitamin D, specifically vitamin D-dependent rickets (VDDR) types I and II. Both types presented with rickets symptoms despite adequate vitamin D intake. VDDR II was also associated with alopecia, though the reasons were unclear. VDDR I was caused by a defect in the gene encoding the enzyme 1α-hydroxylase, leading to decreased production of the active form of vitamin D. VDDR II resulted from mutations in the gene for the vitamin D receptor, affecting hormone or DNA binding. Both conditions were inherited in an autosomal recessive manner.
52 citations,
August 1993 in “Clinical endocrinology” Intravenous and oral calcium effectively treated vitamin D dependent rickets type II, improving growth and bone health.
50 citations,
October 1986 in “European journal of pediatrics” A boy with severe Vitamin D-resistant rickets did not respond to treatment and lacked a common symptom, suggesting a need for alternative treatments.
110 citations,
November 1984 in “The American Journal of Medicine” A genetic defect in vitamin D receptors causes severe rickets and hair loss in children, but some heal as they age.
88 citations,
October 1983 in “The Journal of clinical endocrinology and metabolism/Journal of clinical endocrinology & metabolism” Patients with this syndrome can have different responses and worsening resistance to treatment over time.
82 citations,
April 1981 in “Clinical endocrinology” A girl with rickets and hair loss was found to have a rare condition where her body didn't respond to vitamin D treatment.
4 citations,
January 2017 in “Journal of pediatric endocrinology & metabolism/Journal of pediatric endocrinology and metabolism” Two different mutations in the vitamin D receptor gene cause different symptoms and responses to treatment in Lebanese patients with hereditary rickets.
6 citations,
August 1989 in “European journal of pediatrics” Child with rickets improved with a specific vitamin D therapy, but alopecia did not change.
107 citations,
March 2014 in “BoneKEy Reports” Mutations in the vitamin D receptor cause hereditary vitamin D-resistant rickets, leading to poor bone health and requiring high calcium doses for treatment.
151 citations,
June 2010 in “Endocrinology and metabolism clinics of North America” Two rare genetic diseases cause severe rickets in children due to defects in vitamin D metabolism.
11 citations,
January 2017 in “Biochemical and biophysical research communications” 1α,25-dihydroxyvitamin D3 directly affects cartilage growth and development.
