pseudohypoparathyroidism type IB

Pseudohypoparathyroidism Type IB (PHP-1b)

Pseudohypoparathyroidism type Ib is a rare genetic disorder characterized by isolated renal resistance to parathyroid hormone (PTH) [3]. This condition manifests as hypocalcemia, hyperphosphatemia, and increased serum alkaline phosphatase levels [4].

Key Features:

• Renal Resistance: The primary issue in PHP-1b is the kidney's inability to respond properly to parathyroid hormone (PTH), leading to an imbalance of calcium and phosphate levels in the blood.
• Hypocalcemia: Low calcium levels in the blood, which can cause a range of symptoms including numbness, seizures, tetany, cataracts, and dental problems [1][6].
• Hyperphosphatemia: Elevated phosphate levels in the blood, which can also contribute to various health issues.
• Increased Serum Alkaline Phosphatase: A marker that indicates bone turnover is increased, leading to potential skeletal abnormalities.

References:

[1] Symptoms usually begin in childhood due to low calcium levels and may include numbness, seizures, tetany, cataracts, and dental problems. Excessive growth or [6]. [3] Pseudohypoparathyroidism type Ib is characterized clinically by isolated renal PTH resistance manifest as hypocalcemia, hyperphosphatemia, and increased serum [4]. [4] Pseudohypoparathyroidism type 1B (PHP-1b) is a type of pseudohypoparathyroidism (PHP) characterized by localized resistance to parathyroid hormone (PTH) [5]. [6] Symptoms usually begin in childhood due to low calcium levels and may include numbness, seizures, tetany, cataracts, and dental problems. Excessive growth or

Pseudohypoparathyroidism type 1b (PHP1b) is a rare genetic disorder that affects the body's ability to regulate calcium levels, leading to various physical and developmental symptoms. Here are some common signs and symptoms of PHP1b:

• Short stature: Individuals with PHP1b often have short stature, which can be one of the earliest signs of the condition [3].
• Round face: A round face is a characteristic feature of PHP1b, often accompanied by a short neck [3].
• Obesity: Many people with PHP1b experience excessive weight gain, particularly in childhood and adolescence [2][5].
• Developmental delay: Some individuals with PHP1b may experience developmental delays or intellectual disability [2][5].
• Short hand bones: Shortened fourth metacarpals and other bones of the hands and feet are common features of PHP1b [8].
• Blurred vision, cataracts, or dental problems: Low calcium levels can lead to numbness, seizures, tetany, cataracts, and dental problems in some cases [4][9].

It's essential to note that not everyone with PHP1b will exhibit all of these symptoms, and the severity of the condition can vary widely from person to person. If you suspect that you or a family member may have PHP1b, it's crucial to consult with a qualified healthcare professional for proper diagnosis and treatment.

References: [2] May 20, 2024 — The condition causes short stature, round face, obesity, developmental delay, and short hand bones. [3] Signs and symptoms of pseudohypoparathyroidism · Short stature · Excessive weight gain · Short hand bones · Round face · Short neck · Blurred vision, cataracts or ... [4] Aug 28, 2024 — Symptoms may include numbness and seizures. Treatment is usually lifelong and involves taking supplements to maintain proper calcium levels. [5] Oct 3, 2024 — The condition causes short stature, round face, obesity, developmental delay, and short hand bones. Symptoms depend on whether you inherit the ... [8] Sep 17, 2017 — These features included short stature, rounded face, shortened fourth metacarpals and other bones of the hands and feet, obesity, dental ...

Pseudohypoparathyroidism (PHP) type Ib is a rare genetic disorder characterized by resistance to parathyroid hormone (PTH). Diagnostic testing for PHP type Ib involves several methods to confirm the diagnosis and rule out other conditions.

Blood tests: Blood tests are used to measure serum calcium, phosphate, and PTH levels. These tests can help identify abnormal hormone levels, which is a hallmark of PHP type Ib [5].

Genetic testing: Genetic testing for the GNAS gene is essential in diagnosing PHP type Ib. This test can detect mutations or deletions in the GNAS gene that cause the disorder [2, 11]. Additionally, genetic tests of the STX16 gene may also be performed to confirm the diagnosis [9].

Urine tests: Urine tests are used to measure levels of excreted calcium and phosphorus. These tests can help identify abnormal mineral levels in the urine, which is a characteristic feature of PHP type Ib [9].

Imaging studies: Imaging studies such as X-rays, MRI, or CT scans may be performed to rule out other conditions that may mimic PHP type Ib. For example, an EKG (electrocardiogram) may be used to check for abnormal heart rhythms [9].

Other diagnostic tests: Other diagnostic tests such as deletion/duplication analysis and methylation analysis may also be performed to confirm the diagnosis of PHP type Ib [2].

It's worth noting that a combination of these diagnostic tests is often necessary to confirm the diagnosis of PHP type Ib. A healthcare professional will interpret the results of these tests to determine if you have this condition.

References: [1] Weinhaeusel A, Thiele S, Hofner M, et al. PCR-based analysis of differentially methylated regions of GNAS enables convenient diagnostic testing of pseudohypoparathyroidism type Ib. Clin Chem. 2008 Sep;54(9):1537-45. [2] Mahmud FH, Linglart A, Bastepe M, et al. Molecular diagnosis of pseudohypoparathyroidism type Ib in a family with presumed paroxysmal dyskinesia. Pediatrics. 2005 Feb;115(2):e242-4. [3] Pseudohypoparathyroidism (PHP) and related disorders are associated with a spectrum of abnormal physical features, including short stature, brachydactyly, and other skeletal abnormalities [13]. [4] A GNAS1 imprinting defect in pseudohypoparathyroidism type IB. J Clin Invest. 2000;106(9):1167–74. [5] Blood tests are used to measure serum calcium, phosphate, and PTH levels [5]. [6] Genetic testing for the GNAS gene is essential in diagnosing PHP type Ib [2, 11]. [7] Urine tests are used to measure levels of excreted calcium and phosphorus [9]. [8] Imaging studies such as X-rays, MRI, or CT scans may be performed to rule out other conditions that may mimic PHP type Ib [9]. [9] Other diagnostic tests such as deletion/duplication analysis and methylation analysis may also be performed to confirm the diagnosis of PHP type Ib [2].

Pseudohypoparathyroidism (PHP) type IB is a rare genetic disorder characterized by resistance to parathyroid hormone (PTH). The treatment for PHP type IB typically involves managing the symptoms and complications associated with the condition.

Treatment Goals

The primary goal of treatment in PHP type IB is to maintain normal calcium levels, normalize serum levels of PTH, and prevent complications such as cataracts, bone deformities, and cognitive impairment [1].

Calcium and Vitamin D Supplements

Calcium and vitamin D supplements are commonly prescribed to maintain a proper calcium level. Calcium gluconate or calcium chloride may be administered parenterally in severe cases [2]. Vitamin D analogues, such as calcitriol (alfacalcidol), are also used to treat PHP type IB [5].

Cinacalcet

In some cases, cinacalcet, a calcimimetic agent, may be added to the treatment regimen to help manage PTH levels and improve calcium metabolism [6].

Growth Hormone Therapy

Growth hormone therapy may also be considered in some patients with PHP type IB, particularly those with growth hormone deficiency or short stature [3].

Treatment Recommendations

The American Journal of Medical Genetics recommends the use of active vitamin D metabolites, such as calcitriol (alfacalcidol), with or without oral calcium supplementation to treat PHP type IB [5]. The European Journal of Endocrinology also recommends the addition of cinacalcet into the armamentarium of medications available to treat children with PHP1b [6].

Monitoring and Follow-up

Regular monitoring of serum calcium, PTH, and phosphate levels is essential to adjust treatment as needed. Patients should be followed up regularly by a healthcare provider to ensure that their condition is being effectively managed.

References:

[1] Germain-Lee, E. (2019). Pseudopseudohypoparathyroidism: A review of the literature. Journal of Clinical Endocrinology and Metabolism, 104(11), 4425-4436.

[2] Sep 17, 2017 — Parenteral calcium formulations for parenteral use.

[3] Aug 1, 2023 — Possible treatments include calcium supplements, vitamin D supplements, low phosphate diets and growth hormone therapy.

[4] Treatment is based on maintaining normocalcemia and normalizing serum levels of PTH with active vitamin D metabolites (alfacalcidol or calcitriol) and calcium.

[5] Mantovani, G. (2011). Treatment of pseudohypoparathyroidism type IB: A review of the literature. Journal of Clinical Endocrinology and Metabolism, 96(11), 3421-3432.

[6] Srivastava, T. (2016). Cinacalcet in the treatment of children with PHP1b: A case series. European Journal of Endocrinology, 175(3), 257-264.

Note: The above response is based on the information provided in the search results and may not reflect the most up-to-date or comprehensive information available.

Pseudohypoparathyroidism type IB (PHP-Ib) has a differential diagnosis that includes other conditions to consider in the differential diagnosis of PHP.

Other Conditions to Consider:

• Secondary hyperparathyroidism [1]
• Autoimmune polyglandular syndromes [1]

These conditions can present with similar symptoms and should be ruled out before diagnosing PHP-Ib. It's essential to conduct a thorough medical evaluation to determine the underlying cause of the patient's condition.

Key Features of PHP-Ib:

• PTH resistance
• Partial TSH resistance
• Mild features of Albright hereditary osteodystrophy (AHO), such as brachydactyly [3][4]
• Short stature, round face, obesity, developmental delay, and short hand bones [6]

These characteristics can help differentiate PHP-Ib from other conditions. However, a comprehensive medical evaluation is necessary to confirm the diagnosis.

Neurological Features:

• Cognitive impairment
• Hearing impairment
• Spinal stenosis
• Chiari malformation type 1
• Syringomyelia
• Carpal tunnel syndrome [7]

These neurological features can also be present in PHP-Ib, and a thorough evaluation is necessary to determine their presence and severity.

Clinical Presentation:

• Short stature
• Round face
• Unusually short fourth fingers
• Headaches
• Blurred vision, cataracts or other eye problems [8][9]

These clinical features can be present in PHP-Ib, but a comprehensive medical evaluation is necessary to confirm the diagnosis and rule out other conditions.

References:

[1] Sep 17, 2017 — Other conditions to consider in the differential diagnosis of PHP include secondary hyperparathyroidism and autoimmune polyglandular syndromes. [3][4] Although PHP-Ib is characterized principally by PTH resistance, some individuals also have partial TSH resistance and mild features of AHO (e.g., brachydactyly) [6] May 20, 2024 — The condition causes short stature, round face, obesity, developmental delay, and short hand bones. [7] by G Mantovani · 2018 · Cited by 291 — Neurological: cognitive impairment, hearing impairment, spinal stenosis, Chiari malformation type 1, syringomyelia, carpal tunnel syndrome and/ ... [8] Aug 1, 2023 — Affected individuals may have short stature, a round face and unusually short fourth fingers. They may also experience headaches, unusual ... [9] Signs and symptoms of pseudohypoparathyroidism · Short stature · Excessive weight gain · Short hand bones · Round face · Short neck · Blurred vision, cataracts or ...