Dental manifestations of pseudo-vitamin-D deficiency rickets in a paediatric patient

Vitamin D–resistant rickets shows the resistance to vitamin D (Vit-D) therapy, which traditionally works well in cases with deficiency rickets. The signs start appearing as early as in the first month of life and are characterised by the defective mineralisation at the ends of cartilage and bones despite having normal Vit-D levels in the serum. This case report highlights the dental and maxillofacial manifestations in a 3-year-old girl diagnosed with pseudo-Vit-D deficiency rickets. The report also highlights the variations in the dental manifestations of the condition reported in the literature.

A Neglected Case of Wilson’s Disease Presenting as Symptomatic Urolithiasis and Proteinuria

We report a short-statured, 39-year-old male presenting with recurrent kidney stones, history of refractory rickets, and bone deformity. He had been consuming multiple doses of calcium supplements and multiple courses of vitamin D over past 30 years beforeprior to reporting in our clinic without any significant laboratory or clinical improvement. The patient was diagnosed as having Fanconi’s syndrome attributable to Wilson’s disease. This patient highlighted that in case of resistant rickets, a high index of uncertainty must be invoked for Wilson’s disease. Appropriate timely recognition of this entity results in prompt ministrations and prevention of disability. We also presented and discussed reviews on Wilson’s disease from literature.

Hereditary vitamin D-resistant rickets: a report of four cases with two novel variants in the VDR gene and successful use of intermittent intravenous calcium via a peripheral route

BackgroundHereditary vitamin D-resistant rickets (HVDRR) is caused by vitamin D receptor (VDR) defects. Patients with HVDRR do not respond to standard doses of calcitriol and oral calcium (Ca) treatment and need to be treated with intravenous Ca (IV-Ca) via a central route. However, central catheter-related complications can cause significant morbidity.Case presentationFour unrelated patients with HVDRR presenting with rickets and alopecia totalis were administered intermittent IV-Ca treatment (2–5 times/week) through a peripheral route. No complications such as infection, extravasation or arrhythmias were detected upon peripheral infusion. Peripheral 1–22 months’ duration of IV-Ca normalized parathyroid hormone (PTH) and alkaline phosphatase (ALP) in all patients, after which, oral Ca of 200–400 mg/kg/day and calcitriol of 0.5 μg/kg/day were sufficient to maintain normal PTH levels. Molecular studies on the VDR gene showed a previously reported homozygous c.454C > T (p.Q152*) pathogenic variant in two patients. Two novel homozygous variants in the other two patients were detected: (1) c.756-2A > G, which affects the splice acceptor site, and (2) c.66dupG (p.I23Dfs*20) variant leading to a frameshift that results in a premature stop codon.ConclusionsPeripheral IV-Ca treatment is an effective and practical alternative treatment mode that provides dramatic clinical benefit in patients with HVDRR.

Cinacalcet treatment experience in hereditary vitamin D resistant rickets

BackgroundHereditary vitamin D resistant rickets (HVDRR) is a bone disorder characterized by a phenotype of rickets with onset at early stage of life with elevated alkaline phosphatase, hypocalcemia, hypophosphatemia, hyperparathyroidism and elevated levels of 1,25-dihydroxyvitamin D (calcitriol) as a consequence of the resistance of the vitamin D receptor (VDR). Mutations in the DNA-binding domain of the VDR of the vitamin D receptor have been characterized by a lack of response to traditional treatment with calcium and calcitriol. Secondary hyperparathyroidism and hypophosphatemia are the main factors in its pathogenesis. Cinacalcet is a calciomimetic drug that reproduces the action of calcium by increasing the sensitivity of the calcium-sensitive receptors (CASR) of the parathyroid glands that regulate the secretion of the parathyroid hormone (PTH).Case presentationWe describe its effectiveness and safety in a patient with HVDRR and review other published report cases in the literature. According to published experience, cinacalcet could be used as an adjunctive treatment for the HVDRR with mutations in the DNA-binding domain of the VDR refractory to traditional treatment. Due to lack of knowledge of possible effects of cinacalcet on CASR in the skeleton, long-term use should be avoided.ConclusionsThe optimal dose of cinacalcet for treatment of HVDRR ranges between 0.25 and 0.5 mg/kg/day. Serious side effects of cinacalcet have not been published in this type of patient, although we considered that a close monitoring is necessary in order to detect hypocalcemia.