Respiratory insufficiency as a rare presentation in a child with vitamin D-dependent rickets type 1

Rickets in children usually present with skeletal manifestations. However, they can also rarely present with extraskeletal manifestations, one of them being respiratory insufficiency. We present an unusual case of a girl in early childhood with respiratory insufficiency, which turned out to be due to the underlying vitamin D-dependent rickets (VDDR). The girl was born to third-degree consanguineous parentage and had progressive skeletal deformities, acquired loss of motor milestones, recurrent lower respiratory tract infections and florid signs of rickets. She was hospitalised for respiratory insufficiency, which required prolonged oxygen supplementation. X-rays showed multiple fractures and florid rickets. Laboratory parameters revealed low serum calcium and phosphorus, high alkaline phosphatase, parathyroid hormone and 25-OH vitamin D levels with a normal 1,25-OH2D level. Genetic testing confirmed autosomal recessive CYP27B1 mutation proving VDDR1A. She was started on calcitriol and calcium which led to her gradual improvement.