Clinical Scenario:
A 9-year-old boy with stage 5 chronic kidney disease presents with progressive bone pain, difficulty walking, and poor height gain. On examination, he has genu valgum and tenderness over the long bones. Laboratory investigations reveal:
- Serum calcium: 7.8 mg/dL
- Serum phosphate: 7.0 mg/dL
- Alkaline phosphatase: 750 IU/L
- Parathyroid hormone: Markedly elevated
What is the most appropriate treatment for this child?
A. Calcitriol
B. Iron therapy
C. Prednisolone
D. Sodium bicarbonate
E. Vitamin C
Correct answer & Explanation
Correct Answer: A. Calcitriol
Explanation
This child has renal osteodystrophy (CKD-mineral and bone disorder) due to advanced chronic kidney disease. Impaired renal conversion of vitamin D to its active form leads to hypocalcemia, secondary hyperparathyroidism, and defective bone mineralization. Calcitriol (active vitamin D) suppresses parathyroid hormone secretion and improves calcium absorption, making it a cornerstone of treatment. Hyperphosphatemia should also be managed with dietary phosphate restriction and phosphate binders.
Learning Point:
Renal osteodystrophy is characterized by hypocalcemia, hyperphosphatemia, elevated alkaline phosphatase, and secondary hyperparathyroidism. Treatment includes calcitriol, phosphate binders, dietary phosphate restriction, and optimization of CKD management.
