Diagnosis of X-linked hypophosphatemic vitamin D resistant rickets.Yamamoto T. Acta Paediatr Jpn, 39(4):499-502 1997 Department of Pediatrics, Minoh City Hospital, Osaka, Japan. Recent advances in the pathophysiology and diagnosis of X-linked hypophosphatemic rickets (XLH) are reviewed. The recent discovery of the gene that is responsible for XLH especially enables us to understand the mechanism of hypophosphatemia in XLH. Laboratory and radiological findings are important for the diagnosis. However, dental abnormalities such as spontaneous dental abscess and a defect of dentin maturation are also notable findings.