OVERVIEW

What is congenital hypoparathyroidism?

Congenital hypoparathyroidism is a genetic disorder caused by abnormal development of the parathyroid glands.

What are the symptoms of congenital hypoparathyroidism?

The main manifestations include low blood calcium, high blood phosphorus, reduced parathyroid hormone levels, and increased neuromuscular excitability (such as tetany, seizures, etc.) due to insufficient parathyroid hormone secretion. The disease is often accompanied by developmental or functional defects in other organs, such as salivary gland dysplasia and thymic hypoplasia.

Is congenital hypoparathyroidism common?

Congenital hypoparathyroidism is a rare disease, and few people suffer from it.

What are the types of congenital hypoparathyroidism?

Congenital hypoparathyroidism is classified based on the presence of other organ developmental or functional defects and includes the following types:

• Autoimmune polyendocrinopathy-candidiasis-ectodermal dystrophy (APECED), also known as juvenile familial hypoparathyroidism-Addison disease-mucocutaneous candidiasis syndrome.
• Congenital parathyroid dysplasia.
• DiGeorge syndrome, characterized by abnormal salivary gland development, absence of the thymus and parathyroid glands, often accompanied by cardiovascular and other developmental abnormalities. Most affected infants die in early childhood.
• 22q11 microdeletion syndrome
• 10p deletion syndrome
• 10p13/10p14 deletion syndrome
• HDR syndrome
• CATCH22 syndrome
• Velocardiofacial syndrome
• X-linked or autosomal hereditary hypoparathyroidism
• Type 1 autoimmune polyendocrine syndrome
• Parathyroid hormone gene mutation

SYMPTOMS

What are the common manifestations of congenital hypoparathyroidism?

• The acute manifestations of hypoparathyroidism are caused by acute hypocalcemia, characterized by tetany (often recurrent, typically presenting as stiff hands and feet, thumbs adducted into the palms, other fingers tightly together, extended and rigid, fingers bent toward the palms, and wrists also flexed. In severe cases, the upper arms press against the chest with elbows bent. The lower limbs are extended, feet turned inward, the upper lip contracts, preventing a grin, with generalized muscle rigidity, pain, and a sense of fear. Duration varies from minutes to hours or even days, and symptoms resolve in reverse order of their appearance) and seizures (second only to tetany in frequency).
• Other nonspecific symptoms may include fatigue, extreme irritability, anxiety, and depression. Some patients exhibit no neuromuscular symptoms even with severe hypocalcemia. Cardiac manifestations may include prolonged QT interval, hypotension, heart failure, and arrhythmias. For specific details, refer to the relevant entries.
• Chronic manifestations of hypoparathyroidism include features unique to chronic hypoparathyroidism, such as basal ganglia calcification, cataracts, dental abnormalities, and ectodermal manifestations.

CAUSES

What are the causes of congenital hypoparathyroidism?

Congenital hypoparathyroidism is primarily a genetic disorder caused by gene mutations. It can manifest as autosomal dominant, autosomal recessive, or X-linked inheritance. Some families exhibit abnormalities in the parathyroid hormone gene, while others may present with multiple associated anomalies or developmental defects.

Who is most commonly affected by congenital hypoparathyroidism?

Individuals with a family history of similar conditions have an increased risk of developing the disorder.

Is congenital hypoparathyroidism contagious?

Congenital hypoparathyroidism is not contagious. Some cases are genetic, while others result from underdeveloped or damaged parathyroid glands. The cause remains unknown in certain cases.

Is congenital hypoparathyroidism hereditary?

Congenital hypoparathyroidism has a hereditary tendency and may follow autosomal dominant, autosomal recessive, or X-linked inheritance patterns.

DIAGNOSIS

How is congenital hypoparathyroidism diagnosed?

When diagnosing congenital hypoparathyroidism, doctors primarily consider a family history of similar conditions, the child's specific symptoms (including hypoparathyroidism and manifestations of developmental or functional defects in other organs), and the identification of pathogenic genes.

What tests are needed to diagnose congenital hypoparathyroidism?

• Serum calcium (low), serum phosphorus (high), urinary calcium and phosphorus (low), blood PTH (low), head CT (may show basal ganglia calcification), EEG, slit-lamp eye examination, chest X-ray (to examine the thymus), immune function tests, genetic testing, and comprehensive examinations of the heart, kidneys, etc.
• Parathyroid-related tests: Mainly used to confirm hypoparathyroidism. Refer to relevant entries.
• Examinations for potentially affected organs: Organs that may be involved include the parotid gland, thymus, thyroid, adrenal glands, ovaries, etc. Refer to relevant entries.
• Pathogenic gene testing: Helps confirm the diagnosis.

TREATMENT

Which department should I visit for congenital hypoparathyroidism?

Endocrinology department. In acute episodes, you can go to the emergency department.

Can congenital hypoparathyroidism heal on its own?

Congenital hypoparathyroidism cannot heal on its own and requires lifelong treatment.

How is congenital hypoparathyroidism treated?

Currently, there is no specific cure for congenital hypoparathyroidism. Treatment mainly focuses on symptom management, aiming to relieve symptoms, maintain serum calcium levels at the lower end of the normal range (e.g., 8.0-8.5 mg/dL or 2.0-2.1 mmol/L), and prevent iatrogenic kidney stone formation.
For hypoparathyroidism combined with other organ dysfunctions, refer to the relevant entries.

Does congenital hypoparathyroidism require hospitalization?

Hospitalization or observation is often necessary during acute episodes. If the condition is chronic and stable, hospitalization is not required.

Can congenital hypoparathyroidism be cured?

There is currently no cure for congenital hypoparathyroidism, and lifelong treatment is necessary.

DIET & LIFESTYLE

What should patients with congenital hypoparathyroidism pay attention to in their diet?

The diet for congenital hypoparathyroidism advocates high calcium and low phosphorus intake. High-calcium, low-phosphorus foods mainly include dried shrimp, kelp, seaweed, black fungus, leafy greens, and legumes. Patients should consume calcium-rich, easily absorbed foods and pair them with high-protein or high-lactose foods to improve calcium absorption. At the same time, intake of high-phosphorus foods should be limited, such as dairy products (e.g., milk, cheese), cauliflower, eggs, and other phosphorus-rich foods. Additionally, patients should drink adequate water to prevent constipation.

Does congenital hypoparathyroidism require follow-up examinations? How are they conducted?

Congenital hypoparathyroidism requires regular follow-up examinations, which are crucial for preventing and delaying long-term complications. During treatment, blood calcium, phosphorus, and creatinine levels should be monitored. These indicators should be checked weekly to monthly during medication dosage adjustments and biannually once the dosage stabilizes, along with urine calcium and creatinine levels. If necessary, blood parathyroid hormone levels should also be monitored. For follow-up examinations related to other organ development and functional defects (e.g., parotid glands, thymus, thyroid, adrenal glands, ovaries), please refer to the corresponding entries.

How should patients with congenital hypoparathyroidism be cared for?

Family members of patients with congenital hypoparathyroidism are advised to learn emergency measures for seizures. For example, during a convulsive episode, the patient should immediately lie flat without a pillow, with the head turned to one side. Secretions from the mouth, nasal cavity, and throat should be promptly cleared to maintain airway patency and prevent aspiration-induced choking. If the jaw is clenched, a tongue depressor wrapped in gauze should be placed between the teeth. Avoid forcibly restraining the patient during convulsions to prevent fractures or dislocations. Ensure supervision during episodes to prevent falls or accidents.

PREVENTION

Can congenital hypoparathyroidism be prevented? How to prevent it?

Actively conducting prenatal genetic diagnosis and providing proper prenatal counseling can play a certain role in preventing this disease.