What is Hypopituitarism ?
Hypopituitarism refers to a rare clinical syndrome that is characterized by the low secretion of one or more hormones secreted by the pituitary gland. It is a condition primarily affecting the anterior lobe of the pituitary gland. The hormones that are produced by the pituitary glands and may be affected by hypopituitarism are Adrenocorticotrophic Hormone (ACTH), Antidiuretic Hormone (ADH), Follicle-Stimulating Hormone (FSH), Thyroid-Stimulating Hormone (TSH), Luteinizing Hormone (LH), Growth Hormone (GH) and Prolactin. When any one of these hormones is affected, one is considered to suffer from Partial Hypopituitarism and the case involving several hormones at a time is known as Panhypopituitarism. The German physician, Dr.Morris Simmonds can be credited to have detected and described the first such condition as early as 1914. Both children and adults may suffer from hypopituitarism which may be caused by a number of reasons affecting the pituitary glands. An underactive pituitary gland affects the normal body functions. One who is affected with hypopituitarism since birth or inherits the same, is said to suffer from congenital or postpartum hypopituitarism. However, like hypoparathyroidism, hypopituitarism is a disease that is most likely to last for life, so its treatment also lasts long.
Symptoms of Hypopituitarism
The symptoms of hypopituitarism basically depend on the deficiency of a particular hormone secreted by the pituitary glands and its severity as well as the underlying cause responsible for it as. The signs and symptoms of hypopituitarism are usually subtle in nature but may also appear very suddenly.
In cases such as insufficient gonadotropins production that is actually secreted by the follicle-stimulating hormone and the luteinizing hormone, one may experience sexual problems such as hot flashes, infertility, impotence, loss of pubic hair, decreased sperm production, drying of the vagina, shriveling of the testes, amenorrhea or the absence of menstrual cycle in women and altogether a decreased sex drive. It may also cause osteoporosis in adults. The deficiency of such a hormone may be responsible for delaying puberty in children.
Insufficient production of the growth hormone caused by hypopituitarism in adults usually has no specific symptoms. But growth hormone deficiency may cause hypopituitarism dwarfism in children. This kind of specific hormone deficiency is more associated with people already suffering from tumor in the pituitary glands. One may suffer from the enlargement of the limbs or acromegaly, headaches, autoimmune inflammation of the pituitary glands or lymphocytic hypophysitis, and pituitary apoplexy or stroke.
The deficiency or the poor secretion of the TSH may be signaled by the gain or loss of weight, puffiness or the drying of the skin, sensitivity towards cold, constipation and even cretinism. The poor functioning of the pituitary glands to produce the ACTH or the prolactin results in low blood pressure, fatigue, stress, low blood sugar, anemia and the lack of production of breast milk in women after the birth of a child. On a more general sense, people with hypopituitarism may suffer from skin, nail and hair problems.
The causes of hypopituitarism are quite a few in number and also quite distinct by nature. The most common cause of hypopituitarism is the development of tumor in any of the pituitary glands. Such a condition is also known as pituitary adenomas in which case the normal tissues in the gland are compressed and it may also cause brain tumors, namely, craniopharyngiomas, glioma, chordoma, metastasis, ependymoma, and meningioma that are actually derivatives from pituitary gland problems. Cancer may also aggravate hypopituitarism.
Other common causes of hypopituitarism include hypophysis trauma, brain injury, ill effects of neurosurgical operations and ionizing radiation therapies to cure brain tumors and transsphenoidal adenomectomy.
Infections of the brain or the pituitary glands such as meningitis, brain abscess, syphilis, and encephalitis may also be responsible for causing hypopituitarism. Inflammatory diseases like amyloidosis and sarcoidosis are other causes of hypopituitarism. Diseases associated with infiltration by abnormal cells, histiocytosis and neurosarcoidosis may also be held responsible for hypopituitarism. Autoimmune diseases such as lymphocytic hypophysitis, empty sella syndrome that causes the disappearance of the pituitary tissues, and hemochromatosis or excessive iron content in the body may also be attributed to the occurrence of hypopituitarism.
Vascular hypopituitarism is a disease that affects pregnant women when their pituitary gland is harmed due to hemorrhage or infarction, or excessive bleeding following a delivery, a condition known as Sheehans‘s Syndrome. Pituitary apoplexy and strokes may also be held responsible for the same. On the other hand, congenital hypopituitarism is a disorder that affects a child since his/her birth. It may arise as a result of genetic complications or complications related to the birth. Certain specific gene mutations may cause the poor development of the pituitary glands to such an extent that they even be on the verge of dysfunction. The condition related to the insufficient development of the glands is called hypoplasia. Congenital hypopituitarism may also be caused by the Kallmann Syndrome which causes a deficiency of the sex hormones.
Certain other syndromes such as Prader-Willi and Biedl, chronic metabolic and autoimmune syndromes such as diabetes insipidus may also be responsible for causing hypopituitarism. Any other kind of damage to the nerves or the vessels by either internal or external factors may also cause the deficiency of the pituitary hormones.
Some of the symptoms of hypopituitarism are so obvious and serious that may facilitate the easy diagnosis of the disorder. But for discerning the exact reason behind hypopituitarism, one must go through the proper clinical tests, which shall help in the proper diagnosis of the ailment.
Blood tests are the most common form of clinical test that is beneficial in the proper diagnosis of just not hypopituitarism but for most of the diseases and disorders. The blood tests are usually of two types, namely, basal level tests and dynamic tests. Basal level tests have a specific timing for the collection of blood samples, mostly early morning when one is not stimulated before being injected. One the other hand, dynamic tests requires one to get injected by a stimulant before conducting the actual blood test. Basal level tests are conducted in the case of the measurement of the FSH, TSH and prolactin. Whereas, low levels of growth hormone and ACTH can be detected by the dynamic blood test.
Another way to detect the cause of hypopituitarism is to undergo an x-ray of the neck, hand or the wrist. This is a way most common in cases related to hypopituitarism in children. However, if this method does not prove to be helpful, one may take recourse to the other imaging tests such as CT scan or an MRI.
CT scan or Computed Tomography and MRI are non-invasive diagnosis procedures that helps to detect any kind of abnormality just not associated with the pituitary glands but the body as a whole.
In addition to these, vision tests are conducted specially on children to conform if hypopituitarism tumor has caused any kind of impairment to the eyes. Moreover, in case of congenital hypopituitarism, one may be asked to undergo a genetic test in order to discern the exact cause of hypopituitarism. Urine specific gravity test is used for patients with hypopituitarism and diabetes. All of these diagnostic procedures facilitate the treatment of hypopituitarism.
The treatment for hypopituitarism depends on the underlying cause of the disease that has been detected through the various ways of diagnosis. Some of the treatment methods that are adopted include medicines, drugs, hormone replacement therapy, and radiation therapy. Surgeries and radiation therapies are usually performed in case of pituitary tumors.
The hormone replacement medications perform the similar functions that insulin is supposed to perform in case of diabetes. Such medications help the pituitary glands to artificially produce the hormones that it is deficient in. Some of the most commonly prescribed medications are corticosteroids such as prednisone and hydrocortisone, levothyroxine like synthroid and levoxyl, desmopression, sex hormones, namely, testosterone, progesterone and estrogen, and artificial growth hormones like the somatropin. Corticosteroids help in making up for ACTH deficiency, Levothyroxines help in replacing deficient TSH. Desmopression (DDAVP) or Vasopressin helps in the case of ADH deficiency and also to treat diabetes insipidus. The sex hormones are administered either through the skin to compensate for the deficiency of sex hormones in case of hypopituitarism. In fact, in case of severe hypopituitarism due to FSH and LH deficiency, one may have to be administered gonadotropins to stimulate the production of the sex hormones. The artificially produced growth hormones help in raising the height of children who had to suffer from a stunted growth due to hypopituitarism.
A surgery is usually conducted if one detects a tumor in the vicinity of the pituitary glands. Radiation therapies also serve the purpose of damaging the tumor through powerful radiations.
However, hypopituitarism is a disorder from which one can’t escape till one’s death. So, one need to go through routine tests in order to monitor the effects of the disorder and take precautions to thwart away the complications involved with hypopituitarism. So, undertaking the treatment for hypopituitarism under the supervision of an endicronologist is the best way to keep it on tabs.