Characterizing Cerebral Imaging and Electroclinical Features of Five Pseudohypoparathyroidism Cases Presenting with Epileptic Seizures

Table 1

Characteristics of PHP subtypes with genetic, clinical, and biochemical features [1, 4, 27].

Subtypes	Genetic feature	Clinical features	Biochemical features
PHP1a; OMIM 103580	Maternal LoF of GNAS	AHO; hormone resistance (PTH, TSH, GHRH, and gonadotropins)	Low serum Ca; high serum P; high serum PTH
PHP1b; OMIM 603233	Deletions in STX16 or NESP55; GNAS demethylation	Absence of AHO; hormone resistance (PTH, TSH, GHRH, and gonadotropins)	Low serum Ca; high serum P; high serum PTH
PHP1c; OMIM 612462	Mutation in the C-terminal of Gsα	AHO; hormone resistance (PTH, TSH, GHRH, and gonadotropins)	Low serum Ca; high serum P; high serum PTH
PHP2; OMIM 203330	Unknown	Absence of AHO; no hormone resistance	Low serum ca; high serum P; high serum PTH
PPHP; OMIM 612463	Paternal LoF of GNAS	AHO; no hormone resistance	Normal serum Ca, P, and serum PTH
POH; OMIM 166350	Paternal LoF of GNAS	Deep and invasive heterotopic ossifications	Normal serum Ca, P, and serum PTH

LoF: loss-of-function; PPHP: pseudo-pseudohypoparathyroidism; POH: progressive osseous heteroplasia; AHO: Albright hereditary osteodystrophy; PTH: parathyroid hormone; TSH: thyroid-stimulating hormone; GHRH: growth hormone-releasing hormone; Ca: calcium; P: phosphate.