Prevalence of Chiari malformation type 1 is increased in pseudohypoparathyroidism type 1A and associated with aberrant bone development.

Background: Albright hereditary osteodystrophy (AHO) is caused by heterozygous inactivating mutations in GNAS. Patients with maternally-inherited mutations develop pseudohypoparathyroidism type 1A (PHP1A) with multi-hormone resistance and aberrant craniofacial and skeletal development among other abnormalities. Chiari malformation type 1 (CM1), a condition in which brain tissue extends into the spinal canal when the skull is too small, has been reported in isolated cases of PHP1A.

Management of perinatal HPP during critical illness/ECMO.

Objectives: With the advent of asfotase alfa, the enzyme replacement therapy (ERT) approved for hypophosphatasia (HPP), health care providers need to navigate management of ERT during critical illness.

Case Presentation: We present the case of a young girl, treated with ERT for severe perinatal HPP, who had cardiorespiratory arrest in the setting of influenza A. Her life-saving treatment involving extra corporeal membrane oxygenation (ECMO) required a two-week interruption of ERT leading to persistent hypercalcemia and hyperphosphatemia.