An unusual presentation of vitamin D dependent rickets type 2 with low 25 (OH) D3 levels and alopecia: a case report of two siblings
Keywords:Vitamin-D dependent rickets type 2, Alopecia, 1, 25-dihydroxy vitamin D3
Vitamin D-dependent rickets type 2 (VDDR2) is a rare autosomal recessive (AR) disorder caused either by a mutation in the Vitamin D receptor gene or overexpression of the binding protein leading to end-organ resistance to 1,25 (OH)2 vitamin D3 or defective hormonal actions respectively. It clinically represents growth retardation presenting in the 1st year of life and is frequently associated with alopecia totalis and markedly elevated levels of 1, 25(OH)2 D, which differentiates it from VDDR type 1. We hereby report siblings of a family, who presented with clinical, radiological features of rickets and alopecia totalis. To our knowledge, only a few cases have been reported in literature describing the AR-pattern and low 25(OH)D3 levels in VDDR2.
Angham AM, Rajaa A. Types of rickets. Ann Orthop Rheumatol. 2017;5:1085.
Miller WL. Genetic disorders of Vitamin D biosynthesis and degradation. J Steroid Biochem Mol Biol. 2017;165:101-8.
Soni SS, Adikey GK, Raman AS. Vitamin D dependent rickets type II: Late-onset of disease and response to high doses of Vitamin D. Saudi J Kidney Dis Transpl. 2008;19:796-8.
Greenbaum LA. Vitamin D Deficiency (Rickets) and Excess. In, Kliegman RM (ed). Nelson Textbook of Pediatrics, 21st edition. Philadelphia, Elsevier, 2020;381.
Brooks MH, Bell NH, Love L, Stern PH, Orfei E, Queener SF, et al. Vitamin-D-dependent rickets type II. Resistance of target organs to 1, 25-dihydroxy Vitamin D. N Engl J Med. 1978;298:996-9.
Adam HM, Campbell DE, DeWitt TG, Foy JM, Kamat DM. Formulas and Reference Range Values. In, McInerny TK (ed). AAP Textbook of Pediatric Care, 2nd edition. Washington D.C., American Academy of Pediatrics, 2016;3047-78.
Malla KK, Malla T, Shaw C, Thapalial A. Type II Vitamin D dependent rickets: A case report. J Nepal Paediatr Soc. 2010;30:46-9.
Burmester JK, Wiese RJ, Maeda N, De Luca HF. Structure and regulation of the rat 1,25-dihydroxyvitamin D3 receptor. Proc Natl Acad Sci USA. 1988;85:9499-502.
Malloy PJ, Hochberg Z, Tiosano D. The molecular basis of hereditary 1,25-dihydroxyvitamin D3 resistant rickets in seven related families. J. Clin Invest. 1990;86:2071-9.
Azemi M, Berisha M, Ismaili-Jaha V, Kolgeci S, Hoxha R, Grajçevci-Uka V, et al. Vitamin D - Dependent rickets, type II case report. Mater Sociomed. 2014;26:68-70.
Gamblin GT, Liberman UA, Eil C. Vitamin D-dependent rickets type II. defective induction of 25-hydroxyvitamin D3-24-hydroxylase by 1,25-dihydroxyvitamin D3 in cultured skin fibroblasts. J Clin Invest. 1985;75:954-60.
Inamdar PR, Bellad RM, Herekar VH. Vitamin D-dependent rickets type 2: Alopecia responding to 1, 25 hydroxy Vitamin D. J Sci Soc. 2016;43:155-7.
Kruse K, Feldmann E. Healing of rickets during vitamin D therapy despite defective vitamin D receptors in two siblings with vitamin D-dependent rickets type II. J Pediatr. 1995;126:145-8.
Mishra S, Yadav TP, Nangia S, Gupta VK, Sidhu KK. Vitamin-D dependent rickets type II. Indian Pediatr. 1996;33(4):334-6.
Takeda E, Yokota I, Kawakami I, Hashimoto T, Kuroda Y, Arase S, et al. Two siblings with Vitamin-D dependent rickets type II: No recurrence of rickets for 14 years after cessation of therapy. Eur J Pediatr. 1989;149:54-7.