A Simple Guide to Pseudohypoparathyroidism, Diagnosis, Treatment and Related Conditions

This book describes Pseudohypoparathyroidism, Diagnosis and Treatment and Related Diseases

Pseudohypoparathyroidism (PHP) is a genetic disorder in which the body fails to respond to parathyroid hormone.

A linked disorder is hypoparathyroidism, in which the body does not make sufficient parathyroid hormone.

The parathyroid glands produce parathyroid hormone (PTH).

PTH helps regulate calcium, phosphorus, and vitamin D levels in the blood and is essential for bone health.

If the patient has PHP, the body produces the right amount of PTH, but is "resistant" to its effect.

This causes low blood calcium levels and high blood phosphate levels.

PHP is caused by abnormal genes.

There are 5 types of pseudohypoparathyroidism:
1. PHP type 1a (PHP-1a),
2. PHP type 1b (PHP-1b
3. PHP type 1c (PHP-1c),
4. PHP type 2 (PHP-2),
5. Pseudopseudohypoparathyroidism (PPHP).

All forms are infrequent and are normally diagnosed in childhood.

PHP type 1a is the most frequent subtype and corresponds to 70% of cases.

1. Type 1a is inherited in an autosomal dominant manner.

That indicates only one parent needs to pass the patient the faulty gene for the patient to have the condition.

It is also termed Albright hereditary osteodystrophy.

The disorder causes short stature, round face, obesity, developmental delay, and short hand bones.

Symptoms depend on whether the patient inherits the gene from the mother or father.

2. Type 1b involves resistance to PTH only in the kidneys.

Type 1b is less well known than type 1a.

Blood Calcium is low, but there are none of the other typical features of Albright hereditary osteodystrophy.

3. Type 2 also affects low blood calcium and high blood phosphate levels.

People with this form do not have the physical traits frequent to people with Type 1a.

The genetic abnormality that produces it is not known.

It is different from Type 1b in how the kidney reacts to high PTH levels.

Symptoms are related to a low level of calcium and are:

1. Cataracts
2. Dental problems
3. Numbness
4. Seizures
5. Tetany (a collection of symptoms including muscle twitches and hand and foot cramps and muscle spasms)

People with Albright hereditary osteodystrophy may have these symptoms:
1. Calcium deposits under the skin
2. Dimples that can replace knuckles on affected fingers
3. Round face and short neck
4. Short hand bones, especially the bone below the 4th finger
5. Short height

1. Blood tests will be done to check calcium, phosphorus, and PTH levels.
2. The patient may also need urine tests.
3. Genetic testing
4. Head MRI or CT scan of the brain

Pseudohypoparathyroidism is indicated by the presence of:
1. Hypocalcemia,
2. Hyperphosphatemia,
3. Normal 25 hydroxyvitamin D and
4. Elevated parathyroid hormone levels

The overall purposes in the treatment of PHP are to maintain normal calcium, normal phosphorus, avoid hypercalciuria, and lower PTH levels to normal if possible.

This is important since raised PTH levels in patients with PHP can cause greater bone remodeling and result in hyperparathyroid bone disease.

The use of oral calcium and 1alpha-hydroxylated vitamin D metabolites, such as calcitriol, is the main treatment and should be started in every patient with a diagnosis of PHP.

Patients with severe symptomatic hypocalcemia should be first treated with intravenous calcium.

In the acute setting, the urgent treatment is for intravenous calcium to be given followed by oral calcium and vitamin D supplements.

TABLE OF CONTENT
Introduction
Chapter 1 Pseudohypoparathyroidism
Chapter 2 Causes
Chapter 3 Symptoms
Chapter 4 Diagnosis
Chapter 5 Treatment
Chapter 6 Prognosis
Chapter 7 Hypoparathyroidism
Chapter 8 Hypocalcemia
Epilogue

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