Pseudopseudohypoparathyroidism (PPHP) is an inherited illness, known because of its similarity to pseudohypoparathyroidism in a presentation. It’s more correctly Albright hereditary osteodystrophy but with no immunity of parathyroid hormone often seen in this illness. The expression pseudopseudohypoparathyroidism is used to refer to a state where the person has the phenotypic appearance of pseudohypoparathyroidism type 1a, however, has (sudden for its phenotype) normal labs such as Calcium and PTH.
It may be thought of as a form of Albright hereditary osteodystrophy, or pseudohypoparathyroidism type 1A, since they provide with the exact same constellation of symptoms and signs, such as short stature, brachydactyly, subcutaneous calcification, as well as obesity.
Genetics
A male with pseudohypoparathyroidism has a 50% chance of passing on the defective GNAS gene to his children, although in an imprinted, inactive form. Any of his children receiving this gene will have pseudopseudohypoparathyroidism. Any of his daughters that have pseudopseudohypoparathyroidism may in turn pass along pseudohypoparathyroidism 1A to her children as the imprinting pattern on the inherited paternal gene will be changed to the maternal pattern in the mother’s ovum during meiosis. The gene will be reactivated in any children who inherit it.
Pseudopseudohypoparathyroidism and pseudohypoparathyroidism both involve the same GNAS gene,[8] but pseudopseudohypoparathyroidism has normal calcium homeostasis because of the normal maternal allele in the kidney.
Pathophysiology
The GNAS1 gene involved in both pseudohypoparathyroidism type 1a and pseudopseudohypoparathyroidism is significantly influenced by imprinting. When a dad with pseudohypoparathyroidism undergoes spermatogenesis, imprinting of the GNAS1 gene inactivates both duplicates of the genes: you will be Functional along with another will be faulty. Tissues from your system will re-activate unique copies of the GNAS1 receptor; the kidneys will selectively activate the (functional) maternal copy when maintaining the (faulty) paternally-derived gene discharged and dormant, even in normal people. Considering that the maternally-derived GNAS1 gene is practical, renal handling of calcium and phosphate is ordinary, and homeostasis is maintained in pseudopseudohypoparathyroidism. On the other hand, the remaining cells will rather selectively display the faulty gene, leading to haploinsufficiency of this GNAS1 merchandise in many cells, and providing the phenotype of pseudohypoparathyroidism type 1a. Because of this, there’s also a standard reaction to urinary cAMP into PTH, as well as normal serum PTH.
Treatment of Pseudopseudohypoparathyroidism
Treatments are conservative to relieve any symptoms, with Genetic counseling recommended.
