Natural History of Perinatal and Infantile Hypophosphatasia: A Retrospective Study

Objective To report clinical characteristics and medical history data obtained retrospectively for a large cohort of pediatric patients with perinatal and infantile hypophosphatasia. Study design Medical records from academic medical centers known to diagnose and/or treat hypophosphatasia were reviewed. Patients born between 1970 and 2011 with hypophosphatasia and any of the following signs/symptoms at age NCT01419028 ). Patient demographics and characteristics, respiratory support requirements, invasive ventilator–free survival, and further complications of hypophosphatasia were followed for up to the first 5 years of life. Results Forty-eight patients represented 12 study sites in 7 countries; 13 patients were alive, and 35 were dead (including 1 stillborn). Chest deformity, respiratory distress, respiratory failure (as conditioned by the eligibility criteria), failure to thrive, and elevated calcium levels were present in >70% of patients between birth and age 5 years. Vitamin B6–dependent seizures and respiratory distress and failure were associated significantly ( P Conclusions Patients with perinatal or infantile hypophosphatasia and vitamin B6–dependent seizures, with or without significant respiratory distress or chest deformities, have high morbidity and mortality in the first 5 years of life. Trial registration ClinicalTrials.gov : NCT01419028 .