IMPE Abstracts

Background: Hypophosphatemic rickets is a disorder of bone mineralization due to defects in the renal handling of phosphorus, which can either be inherited or acquired. X-linked hypophosphatemic rickets is the commonest inherited from. It presents with progressive limb deformities such as coxa vara, genu valgum leading to disproportionate short stature. We present the first case report from Botswana.

Objectives: To report on an eight-year old girl with hypophosphatemic rickets who had presented at 3 years 3 months with a non-traumatic buckle fracture of her distal left femur to the orthopedic department. She had a history of limping, painful knees and genu valgus which had been managed at the local facility with analgesics which had been getting worse since 2 years 2 months, prior to referral to orthopaedics. She was also noted to have anterior bowing of her femur/ thigh. She had bilateral femur fractures 5 months later and a differential diagnosis of osteogenesis imperfecta type 1 and rickets were entertained and referred to paediatric endocrinology for evaluation. She was also noted to have frontal bossing, dental caries, anterior bowing of distal radius and ulna.

Results: Initial x-rays showed osteopenic femurs with healed fractures. Her laboratory investigations showed normal calcium, low phosphate, PTH upper limit of normal and lower normal Vitamin D levels which will be keeping with hypophosphatemic rickets, possibly X-linked hypophosphatemic type. Treatment with both oral phosphate and calcitriol stabilized her condition.

Conclusion: Hypophosphatemic rickets is a diagnostic challenge in our setting especially in the peripheral areas and education is needed to ensure earlier referral to the endocrine center. It’s a management challenge needing multidisciplinary team approach.