Unusual presentation of Wilson's disease as proximal renal tubular acidosis with isolated phosphaturia

An adolescent girl presented with recurrent lower limb fractures and was managed as osteogenesis imperfecta. Low phosphate levels noted on routine investigation were the clue for the phosphaturia and subsequent diagnosis of proximal renal tubular acidosis (RTA). Further, with a history of jaundice, she was diagnosed with Wilson's disease, which was the underlying cause of proximal RTA with isolated phosphaturia and consequent fractures. Standard treatment for Wilson's disease along with supplementation of oral phosphate and bicarbonate led to complete recovery of fragile bones.