Pseudohypoparathyoridism Flashcards
(13 cards)
What is pseudohypoparathyroidism?
A rare genetic disorder where target organs fail to respond to normal levels of parathyroid hormone due to defects in the PTH receptor
It contrasts with hypoparathyroidism, which involves a deficiency of the parathyroid hormone itself.
What is the primary genetic cause of pseudohypoparathyroidism?
Mutations in the GNAS1 gene
The GNAS1 gene codes for the alpha subunit of the Gs protein, crucial for PTH action.
List the signs and symptoms of pseudohypoparathyroidism.
- Short stature
- Shortened 4th and 5th metacarpals
- Hypocalcemia leading to:
- Numbness or tingling of fingers and toes
- Muscle cramps
- Carpopedal spasm
- Seizures
- Chvostek’s sign
- Trousseau’s sign
- Symptoms related to vitamin D deficiency
Symptoms can be similar to those of hypoparathyroidism.
What is Chvostek’s sign?
Twitching of the face after tapping the facial nerve
It is a clinical sign associated with hypocalcemia.
What is Trousseau’s sign?
Carpopedal spasm after inflating a blood pressure cuff
It indicates low calcium levels.
What are key conditions to consider in the differential diagnosis of pseudohypoparathyroidism?
- Hypoparathyroidism
- Vitamin D deficiency
- Hypocalcemia due to other causes
Each condition presents with overlapping symptoms but has distinct features.
What biochemical findings support the diagnosis of pseudohypoparathyroidism?
- Hypocalcemia on serum calcium levels
- Normal or elevated levels of parathyroid hormone
Diagnosis is primarily clinical, supported by these findings.
What is the main focus of management for pseudohypoparathyroidism?
Managing hypocalcemia and maintaining normal serum calcium levels
This typically involves calcium and vitamin D supplementation.
Fill in the blank: Pseudohypoparathyroidism is characterized by a failure of target organs to respond to _______.
normal levels of parathyroid hormone
True or False: Pseudohypoparathyroidism is caused by a deficiency of parathyroid hormone.
False
The disorder is due to receptor defects, not a deficiency of the hormone itself.
What is a key feature of pseudohypoparathyoridism?
Shortening of metacarpals
What is the most appropriate initial treatment?
The most appropriate initial management for acute severe hypocalcaemia is intravenous calcium gluconate as it rapidly increases serum calcium levels.
What is the general treatment for acute hypocalcaemia? i
IV calcium gluconatw
