Pseudo-hypothyroidism
Pseudo-hypothyroidism (PHP) is a rare genetic disorder that manifests itself in the form of disturbances of phosphorus and calcium metabolism due to parathyroid hormone (PTH) resistance. The clinical variant of PHP depends not only on PTH resistance: there is a phenotype attributable to multi-hormonal resistance. PTH resistance is associated with the disturbance of activity of the alpha-subunit in G-protein due to a defect in the GNAS gene and epigenetic variations. The mechanism underlying the development of this rare (orphan) condition is highly complicated and remains to be elucidated. The present review reflects the modern views of etiology, pathogenesis, and clinical variability of pseudohypothyroidism.