Case-1: A 13-year-old boy with knee deformity and periodic paralysis: to be or not to be Rickets

Case summary

A 13-year-old boy with knee deformity, and difficulty walking since 3 years of age presents for evaluation. He was labeled as Rickets earlier at 7 years of age. Initially, it was presumed to be a case of Nutritional Rickets but by the age of 10 years, it turned out to be Hypophosphatemic Rickets. However, the child’s condition was not responding to the treatment advised to him like calcium and cholecalciferol. In 2022 at 12.5 years of age, he suddenly developed periodic paralysis of both lower limbs. During evaluation along with low calcium and phosphate, severe hypokalemia and normal anion gap metabolic acidosis were revealed. How should this case be evaluated and managed?