Hypoparathyroidism is caused by insufficient or inactive parathyroid hormone secretion, or simply put, low PTH. There are a number of conditions under which this happens, and they all have different causes.
These conditions are divided into two main types of hypoparathyroidism:
1) Iatrogener Hypoparathyreoidismus
The most common form of hypoparathyroidism is caused by surgical removal or damage to the parathyroid glands. It is usually referred to as postoperative or postoperative hypoparathyroidism (PoSH).
(Iatrogenic means caused by treatment.)
2) Idiopathischer Hypoparathyreoidismus
The rarer forms of hypoparathyroidism are summarized under the headingIdiopathischer Hypoparathyreoidismus. This group of rare diseases can beinnate(occurring in the womb) or acquired in childhood or later in life as ainheritedIAutoimmuneCondition. The term "idiopathic" is also used to denote a form of hippopara of unknown cause.
Iatrogener Hypoparathyreoidismus
a) Postoperative
This is the most common cause of adult hypoparathyroidism, although it is still a rare condition. Permanent hypoparathyroidism occurs in about 7-10% of all neck surgeries. The British Association of Thyroid and Endocrine Surgeons (BAETS) says around 30% of people who have thyroid surgery have temporary symptoms of low calcium and may need treatment. If treatment is continued after 6 months, this is called "late hypocalcemia" or hypoparathyroidism and can be permanent and require lifelong medication. Late hypocalcemia after total thyroidectomy is the most commonly reported complication. The overall incidence is approximately 9%.*
Hypoparathyroidism can occur after any surgery of the neck (thyroid, parathyroid, larynx, or esophagus) in which the parathyroid glands have been accidentally or intentionally removed or damaged and have lost their blood supply. For example, during thyroid surgery, the parathyroid glands can be accidentally damaged or removed.
The parathyroid glands can also be removed intentionally when they are cancerous (although this is extremely rare) or to treat hyperparathyroidism when the parathyroid glands are overactive.
Postoperative hypoparathyroidism can be ain the interimSituation: If enough uninjured parathyroid tissue remains or the remaining tissue is no longer suppressed, the parathyroid glands usually recover within 6 months to a year. If parathyroid hormone levels remain above 18 ng/L, there is a good chance that patients will eventually be able to stop taking their medication. If this is not the case,continuousleads to hypoparathyroidism.
b) radiotherapy or pharmacological treatment
Hypopara can be caused by treatment for thyroid and other cancers, e.g. B. ablation of the thyroid with radioactive iodine or external irradiation of the neck or the use of chemotherapy drugs. It can also occur in parathyroid cancer, HIV, and AIDS.
c) Hungry-Bone-Syndrom
This is a temporary situation that can sometimes develop after parathyroidectomy for primary hyperparathyroidism. In this case, the body has become accustomed to the high levels of calcium entering the blood from the bones. When the parathyroid gland or glands are removed, the level of PTH in the blood suddenly drops and the patient becomes temporarily hypoparathyroid. The bone that was deprived of calcium now rebuilds it and the calcium level in the blood drops suddenly. This requires several days of postoperative calcium treatment until the hypoparathyroid condition resolves and calcium levels stabilize.
Idiopathischer Hypoparathyreoidismus
The term idiopathic hypoparathyroidism is used to describe a number of very rare disorders that may be autoimmune, congenital, genetic, or have no defined cause (such as surgery).
a) Congenital hypoparathyroidism
Congenital hypoparathyroidism is a lifelong condition in which the development of the parathyroid glands is impaired at or before birth. It can be acquired during fetal development or it can beinherited. People with this condition are born without parathyroid tissue, as inDiGeorge Syndrome
b) Inherited genetic hypoparathyroidism
Other terms may be communicated by yourGenethrough your family and can occur in childhood or later in life.
The basicsinheritance patternThey are: autosomal dominant, autosomal recessive and X-linked inheritance.
These inherited forms of hypoparathyroidism are caused by faulty genes that affect the proper functioning of parathyroid hormone in the body in various ways.
- Gland development in utero as inDiGeorge Syndrome
- the calcium-sensitive receptor gene
- the PTH gene
- PTH effect as in
Hereditary osteodystrophy according to Albright, pseudohypoparathyroidism (PHP) and pseudopseudohypoparathyroidism (PPHP).These forms are very rare. You appear to have hypoparathyroidism but you are not; hence the name pseudo-hypoparathyroid.
Pseudohypoparathyreoidismus (PHP)
There are different types of pseudohypoparathyroidism:1a, 1b, 1c and 2.
In this condition, the glands produce parathyroid hormone, but the body is resistant to it. So even though PTH levels are normal or high, the body cannot respond normally and causes low calcium levels. The phosphate level can be normal or high. People with PHP are typically short, with shortened bones in their feet and hands. They may also have diabetes and an underactive thyroid.
Type Ia is inherited in an autosomal dominant manner. This means that only one parent needs to pass on the faulty gene for it to develop the disease. The condition causes short stature, a round face, and short hand bones, as in Albright's hereditary osteodystrophy. Type Ib also includes PTH resistance, but only in the kidneys. It is less well known than Type Ia and has no skeletal abnormalities. In type 1c, the protein shows normal activity.
Type 2 pseudohypoparathyroidism also involves low blood calcium and high blood phosphate but none of the physical characteristics observed in 1a. Type 2 has not yet been genetically characterized.
Pseudopseudohypoparathyreoidismus (PPHP)
Patients with this condition have all the hallmarks of pseudohypothyroidism (PHP), but calcium and phosphate levels are normal. Levels can fluctuate.
c) Autoimmune hypoparathyroidism
In an autoimmune disease, the body's autoantibodies attack normal cells instead of infections. In autoimmune hypoparathyroidism, autoantibodies attack the cells of the parathyroid glands. It can exist alone or insporadicÖtrustedforms of hypoparathyroidism.
Autoimmune diseases can be isolated or part of onePolyglandular SyndromeifPolyglandular autoimmune syndrome type 1 (APS-1).This usually consists of skin infections, hypoparathyroidism, and primary adrenal problems (developing in that order). Also known as APECED. This version is hereditary (autosomal recessive) and usually occurs in children aged 3 to 5 years or early adolescence, but always occurs by age 25.
Polyglandular autoimmune syndrome type 2 (APS-2). This version occurs in adulthood and also occurs as part of a syndrome. CanAddison's disease(adrenal insufficiency) in combination with type 1 diabetes mellitus and thyroid diseases, e.g.Hashimoto's thyroidIMorbus Basedow.75% of cases occur in women and are not linked to any gene.
Isolated idiopathic hypoparathyroidismthey also have a possible autoimmune cause and can be inherited.
d) Genetic Syndrome
Hypoparathyroidism sometimes occurs as part of a developmentgenetic syndromeor group of conditions. InHDR or Barakat SyndromeThere is hypoparathyroidism, deafness and renal dysplasia caused by a GATA3 gene mutation. Inheritance is probably autosomal dominant.
other causes
transient hypoparathyroidism
temporarily orin the interimHypopara can develop in the womb with no family history, so the baby is born with symptoms of low calcium at birth or develops low calcium during the neonatal period.
That can happen when
- the mother's own overactive parathyroid glands have produced too much calcium, temporarily suppressing the baby's parathyroid glands. This version can be longer.
- a delayed increase in PTH that usually occurs at birth. This can sometimes occur in both normal weight babies and very low birth weight premature babies.
- a diabetic mother has low magnesium levels
Altered PTH secretion
Hypomagnesemia
Magnesium is necessary to produce parathyroid hormone. When magnesium levels are too low, calcium levels also drop. A deficiency can be caused by a poor diet, severe burns, alcohol abuse, or malabsorption.
Neonatal suppression due to maternal hypercalcemia.
alcoholism or alcohol withdrawal
HIV or AIDS
infiltration of glands
This is rare but can occur with deposits of heavy metals (such as iron and copper) in the blood, such as in Wilson's disease; metastatic tumors; Riedel's thyroiditis.