Introduction: VDDR II is an autosomal recessive disorder caused by a defect in the vitamin D receptor gene located on chromosome 12q12q14. Thus far, 13 mutations have been identified. It is characterized by hypocalcemia, secondary hyperparathyroidism, and early onset severe rickets. Here we report a case of a severe form of rickets associated with alopecia.
The Case: This 23-month-old boy was born at term to consanguineous parents. He was referred with persistent hypocalcemia; not responding to oral calcium and vitamin D therapy, progressive alopecia capitis and macrocephaly. He had delayed gross motor development with deformed wrist and ankle joints and severe leg bowing. He had been on vitamin D (1400 units/day) and calcium prescribed for 2 months. He did not have any gastrointestinal or urinary symptoms, He did not develop any seizure, abnormal movement recently or impaired consciousness. He had no family history of vitamin D/calcium abnormalities.
Clinically has alopecia capitis, closed fontanelle. His weight = 12.15kg (0.01SD), length = 79.5cm (-2.7 SD) and head circumference 48.8cm (0.48SD) . He had parietal and frontal bossing, rachitic rosaries, Harrison sulcus, widening of the wrist and bowing of the distal radius and ulna and bowing of the femur and tibia. His system examination was otherwise unremarkable.
The radiologic investigation revealed extensive cupping, fraying and splaying of the distal metaphysis of both femora and proximal and distal metaphysis of the tibia and fibula with diffuse osteopenia and cortical thinning of the shafts of the tibia and fibula.
|Before treatment||4 weeks after starting the treatment||Normal values|
|Serum total calcium||1.72 mmol/L||1.62 mmol/L||2.32-2.64|
|Serum phosphate||1.11 mmol/L||1.31 mmol/L||1.45-2.33|
|Serum creatinine||15 mcmol/L||16 mcmol/L||17-36|
|Serum alkaline phosphatase||1,531 IU/L||1,521 IU/L||134-315|
|Serum Magnesium||0.81 mmol/L||0.86 mmol/L||0.70-1.00|
|25 OHD level||69 nmol/L|
|PTH intact molecule||46.3 pmol/L||52.7 pmol/L||1.3-5.8|
|1,25 OH2 vit D||870pmol/l||58-207|
The patient was started on oral elemental calcium (100 mg/kg/day) divided q8 hourly and alfa calcidiol 2 mcg daily. Monitoring showed no improvement in biochemical or radiological parameters after 4 weeks.
Conclusion: Therapy with a high dose of vitamin D analogues with oral calcium was not effective in our case. Higher doses of oral calcium and/or intravenous calcium therapy has been discussed with the parents as a next possible therapy.
19 - 21 Sep 2019
European Society for Paediatric Endocrinology