**Question:** All of the following statements about Pseudohypoparathyroidism are true, except:

A. Pseudohypoparathyroidism is a group of rare genetic disorders characterized by reduced levels of parathyroid hormone (PTH).
B. PTH regulates calcium and phosphate levels in the blood by acting on the kidneys, bones, and intestines.
C. In Pseudohypoparathyroidism, PTH remains normal or elevated but does not function properly.
D. Treatment for Pseudohypoparathyroidism involves oral calcium and vitamin D supplements to increase calcium levels.

**Correct Answer:** D. Treatment for Pseudohypoparathyroidism involves oral calcium and vitamin D supplements to increase calcium levels.

**Core Concept:**
Pseudohypoparathyroidism is a group of genetic disorders characterized by resistance to PTH. This resistance is due to mutations in the Gsα gene, which leads to impaired signaling of PTH and other hormones like aldosterone and thyroid stimulating hormone (TSH) in target tissues. Consequently, despite normal or elevated PTH levels, calcium and phosphate levels remain low.

**Why the Correct Answer is Right:**
In Pseudohypoparathyroidism, PTH does not function properly due to the genetic defect. Since PTH primarily regulates calcium and phosphate levels in the blood by acting on the kidneys, bones, and intestines, oral calcium and vitamin D supplements would not be an effective treatment. Instead, the primary aim of treatment is to manage symptoms and complications, such as seizures, bone pain, and kidney stones.

**Why Each Wrong Option is Incorrect:**

A. While Pseudohypoparathyroidism is characterized by reduced PTH levels, this statement is true as reduced PTH levels are seen in hypoparathyroidism, not Pseudohypoparathyroidism.

B. Treatment for Pseudohypoparathyroidism involves oral calcium and vitamin D supplements to increase calcium levels. This statement is incorrect because, as mentioned earlier, PTH does not function properly and thus calcium levels would not increase with supplementation.

C. In Pseudohypoparathyroidism, PTH remains normal or elevated, but does not function properly. This is consistent with the correct answer, as it highlights the issue with PTH signaling in the disease.

**Clinical Pearls:**
1. Pseudohypoparathyroidism is a rare genetic disorder, and its diagnosis relies on measuring PTH levels and assessing the response to PTH stimulation tests.
2. Treatment focuses on managing symptoms and complications rather than correcting the underlying hormonal imbalance, as oral calcium and vitamin D supplements would not be effective due to impaired PTH function.