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Pseudohypoparathyroidism

Pseudohypoparathyroidism is a genetic disorder in which the body is unable to respond to parathyroid hormone. Parathyroid hormone helps control calcium, phosphorous, and vitamin D levels in the bones and blood

Prevalence

1-9 / 1 000 000

331-2,979

US Estimated

513-4,622

Europe Estimated

Age of Onset

All ages

ICD-10

E20.1

Inheritance Pattern

Autosomal dominant

Autosomal recessive

Mitochondrial/Multigenic

X-linked dominant

X-linked recessive

Interest over time

Google searches

5 Facts you should know

FACT

Pseudohypoparathyroidism (PHP) is a rare inherited endocrine disorder characterized by resistance to parathyroid hormone (PTH), leading to hypocalcemia, hyperphosphatemia, and elevated PTH levels despite normal parathyroid gland function

FACT

The condition arises most commonly from inactivating mutations in the GNAS gene, which disrupts Gsα protein signaling in the PTH receptor pathway

FACT

Clinical manifestations vary depending on subtype: some patients present with Albright’s hereditary osteodystrophy (AHO) features (short stature, brachydactyly, obesity), while others have only biochemical abnormalities without skeletal changes

FACT

Beyond PTH resistance, some forms of PHP also involve resistance to other hormones that act through Gsα–cAMP signaling, such as TSH, gonadotropins, and GHRH, leading to hypothyroidism, hypogonadism, or growth hormone deficiency

FACT

Management includes calcium and vitamin D supplementation to correct hypocalcemia, along with careful monitoring for hormone deficiencies and associated complications across a patient’s lifetime