TSH elevations as the first laboratory evidence for pseudohypoparathyroidism type Ib (PHP-Ib).

ABSTRACT: Hypocalcemia and hyperphosphatemia because of resistance toward parathyroid hormone (PTH) in the proximal renal tubules are the most prominent abnormalities in patients affected by pseudohypoparathyroidism type Ib (PHP-Ib). In this rare disorder, which is caused by GNAS methylation changes, resistance can occur toward other hormones, such as thyroid-stimulating hormone (TSH), that mediate their actions through G protein-coupled receptors. However, these additional laboratory abnormalities are usually not recognized until PTH-resistant hypocalcemia becomes clinically apparent. We now describe four pediatric patients, first diagnosed with subclinical or overt hypothyroidism between the ages of 0.2 and 15 years, who developed overt PTH-resistance 3 to 20 years later. Although anti-thyroperoxi

SUBMITTER: Molinaro A 

PROVIDER: S-EPMC4401615 | biostudies-literature | 2015 May

REPOSITORIES: biostudies-literature