Educational Series: Vitamin D-Resistant Rickets, Helicobacter pylori, Hypothyroidism, Tuberculosis, Upper Airway Obstruction, Haemorrhagic Disease of the Newborn

Case Presentation A boy aged 2-years 8months, presented with progressively worsening, painful abnormal gait and swelling of the wrists, knees and ankles for about a year. He walked at 10 months of age but was noticed to have an abnormal gait. The parents were reassured by neighbours that it was normal and would be self-limiting. He was adopted a few days after birth, and he is the only child of his parents, who are in their forties. He was formula-fed on demand for six months, and thereafter, home-made maize gruel and soyabean powder was added. He was fed about five times a day. By age one year, he was already on regular home staple foods. He lived with his parents in a three-bedroom apartment on the first floor of a two-storey-building. Both parents were school teachers, and he was usually taken to school with them, and also played with other children. There was no chronic drug history, except for multivitamins from time to time. He has had no cause for hospital visits except for immunization. Examination findings: A cheerful toddler who weighed 12kg (15th centile for age) with standing height of 85cm (