The hormones of the pituitary have different actions in the body, and the symptoms of hypopituitarism therefore depend on which hormone is deficient. The symptoms may be subtle and are often initially attributed to other causes. In most of the cases, three or more hormones are deficient. The most common problem is insufficiency of follicle-stimulating hormone (FSH) and/or luteinizing hormone (LH) leading to sex hormone abnormalities. Growth hormone deficiency is more common in people with an underlying tumor than those with other causes. Sometimes, there are additional symptoms that arise from the underlying cause; for instance, if the hypopituitarism is due to a growth hormone-producing tumor, there may be symptoms of acromegaly (enlargement of the hands and feet, coarse facial features), and if the tumor extends to the optic nerve or optic chiasm, there may be visual field defects.
Signs and symptoms
Hypopituitarism
Hypopituitarism | Signs and symptoms
Insufficiency of follicle-stimulating hormone (FSH) and/or luteinizing hormone (LH) leading to sex hormone abnormalities. Growth hormone deficiency is more common in people with an underlying tumor than those with other causes. Sex hormone abnormalities, symptoms of acromegaly, etc. are few among them Insufficiency of follicle-stimulating hormone (FSH) and/or luteinizing hormone (LH) leading to sex hormone abnormalities and growth hormone deficiency. Insufficiency of follicle-stimulating hormone (FSH) and/or luteinizing hormone (LH) leading to sex hormone abnormalities.
hypothalamic amenorrhea will result in the increased secretion of thyroid stimulating hormone (tsh)
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Sorry. I cannot find the answer based on the context.
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what is hypopituitarism?
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A decreased ("hypo") secretion of one or more of the eight hormones normally produced by the pituitary gland at the base of the brain.
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what are the indications of it?
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Hypopituitarism is the decreased ("hypo") secretion of one or more of the eight hormones normally produced by the pituitary gland at the base of the brain. If there is decreased secretion of one specific pituitary hormone, the condition is known as selective hypopituitarism. If there is decreased secretion of most or all pituitary hormones, the term panhypopituitarism ("pan" meaning "all") is used. The signs and symptoms of hypopituitarism vary, depending on which hormones are undersecreted and on the underlying cause of the abnormality. The diagnosis of hypopituitarism is made by blood tests, but often specific scans and other investigations are needed to find the underlying cause, such as tumors of the pituitary, and the ideal treatment.
Hypopituitarism | Introduction
Occasionally, the pituitary hormone may be normal but the effector gland hormone decreased; in this case, the pituitary is not responding appropriately to effector hormone changes, and the combination of findings is still suggestive of hypopituitarism.
Hypopituitarism | Diagnosis
The hormones of the pituitary have different actions in the body, and the symptoms of hypopituitarism therefore depend on which hormone is deficient. The symptoms may be subtle and are often initially attributed to other causes. In most of the cases, three or more hormones are deficient. The most common problem is insufficiency of follicle-stimulating hormone (FSH) and/or luteinizing hormone (LH) leading to sex hormone abnormalities. Growth hormone deficiency is more common in people with an underlying tumor than those with other causes. Sometimes, there are additional symptoms that arise from the underlying cause; for instance, if the hypopituitarism is due to a growth hormone-producing tumor, there may be symptoms of acromegaly (enlargement of the hands and feet, coarse facial features), and if the tumor extends to the optic nerve or optic chiasm, there may be visual field defects.
Hypopituitarism | Signs and symptoms
Children experience growth retardation and short stature.
Hypopituitarism | Anterior pituitary
If the hypopituitarism is caused by the blood loss associated with childbirth, the disorder is referred to as Sheehan syndrome.
Anterior pituitary | Decreased activity
The diagnosis of hypopituitarism is made on blood tests. Two types of blood tests are used to confirm the presence of a hormone deficiency: basal levels, where blood samples are taken–usually in the morning–without any form of stimulation, and dynamic tests, where blood tests are taken after the injection of a stimulating substance. Measurement of ACTH and growth hormone usually requires dynamic testing, whereas the other hormones (LH/FSH, prolactin, TSH) can typically be tested with basal levels. There is no adequate direct test for ADH levels, but ADH deficiency can be confirmed indirectly; oxytocin levels are not routinely measured. Generally, the finding of a combination of a low pituitary hormone together with a low hormone from the effector gland is indicative of hypopituitarism.
Hypopituitarism | Diagnosis
Most hormones controlled by the secretions of the pituitary can be replaced by tablets or injections. Hypopituitarism is a rare disease, but may be significantly underdiagnosed in people with previous traumatic brain injury. The first description of the condition was made in 1914 by the German physician Dr Morris Simmonds.
Hypopituitarism | Introduction
Treatment of hypopituitarism is threefold: removing the underlying cause, treating the hormone deficiencies, and addressing any other repercussions that arise from the hormone deficiencies.
Hypopituitarism | Treatment
Headaches may also accompany pituitary tumors, as well as pituitary apoplexy (infarction or haemorrhage of a pituitary tumor) and lymphocytic hypophysitis (autoimmune inflammation of the pituitary). Apoplexy, in addition to sudden headaches and rapidly worsening visual loss, may also be associated with double vision that results from compression of the nerves in the adjacent cavernous sinus that control the eye muscles. Pituitary failure results in many changes in the skin, hair and nails as a result of the absence of pituitary hormone action on these sites.
Hypopituitarism | Signs and symptoms
Dysfunction of the hypothalamus results in loss of regulation over behavior and function of the pituitary gland (master gland). Hypopituitarism is present in 75% to 80% of patients with ONH. The anterior pituitary gland contributes to growth, metabolism, and sexual development. The most common pituitary endocrinopathies are growth hormone (GH) deficiency (70%), hypothyroidism (43%), adrenal insufficiency (27%), and diabetes insipidus (5%). Absence of GH may often be indicated by short stature, although this is not always the case. Other indicators of GH deficiency may include hypoglycemic events (including seizures), prolonged jaundice, micropenis in boys, and delayed dentition. Testing for GH may involve blood tests (IGF-1 and IGFBP-3), growth hormone stimulation test, or bone age x-ray of the hand or wrist (or body for children younger than 2 years).
Optic nerve hypoplasia | Hypothalamic dysfunction
After traumatic brain injury, as much as a quarter have persistent pituitary hormone deficiencies. Many of these people may have subtle or non-specific symptoms that are not linked to pituitary problems but attributed to their previous condition. It is therefore possible that many cases of hypopituitarism remain undiagnosed, and that the annual incidence would rise to 31 per 100,000 annually if people from these risk groups were to be tested.
Hypopituitarism | Epidemiology
If the TSH level is normal or low and serum free T levels are low, this is suggestive of central hypothyroidism (not enough TSH or TRH secretion by the pituitary gland or hypothalamus). There may be other features of hypopituitarism, such as menstrual cycle abnormalities and adrenal insufficiency. There might also be symptoms of a pituitary mass such as headaches and vision changes. Central hypothyroidism should be investigated further to determine the underlying cause.
Hypothyroidism | Central
The pituitary was known to the ancients, such as Galen, and various theories were proposed about its role in the body, but major clues as to the actual function of the gland were not advanced until the late 19th century, when acromegaly due to pituitary tumors was described. The first known report of hypopituitarism was made by the German physician and pathologist Dr Morris Simmonds. He described the condition on autopsy in a 46-year-old woman who had suffered severe puerperal fever eleven years earlier, and subsequently suffered amenorrhea, weakness, signs of rapid aging and anemia. The pituitary gland was very small and there were few remnants of both the anterior and the posterior pituitary.
Hypopituitarism | History
The hypothalamus and pituitary gland are tightly integrated. Damage to the hypothalamus will impact the responsiveness and normal functioning of the pituitary. Hypothalamic disease may cause insufficient or inhibited signalling to the pituitary leading to deficiencies of one or more of the following hormones: thyroid-stimulating hormone, adrenocorticotropic hormone, beta-endorphin, luteinizing hormone, follicle-stimulating hormone, and melanocyte–stimulating hormones. Treatment for hypopituitarism involves hormone replacement therapy.
Hypothalamic disease | Hypopituitarism
Granulomas in the pituitary gland, which produces numerous hormones, is rare but leads to any of the symptoms of hypopituitarism: amenorrhoea (cessation of the menstrual cycle), diabetes insipidus (dehydration due to inability to concentrate the urine), hypothyroidism (decreased activity of the thyroid) or hypocortisolism (deficiency of cortisol).
Neurosarcoidosis | Endocrine
If one of these tests shows a deficiency of hormones produced by the pituitary, magnetic resonance imaging (MRI) scan of the pituitary is the first step in identifying an underlying cause. MRI may show various tumors and may assist in delineating other causes. Tumors smaller than 1 cm are referred to as "microadenomas", and larger lesions are called "macroadenomas". Computed tomography with radiocontrast may be used if MRI is not available. Formal visual field testing by perimetry is recommended, as this would show evidence of optic nerve compression by a tumor. Other tests that may assist in the diagnosis of hypopituitarism, especially if no tumor is found on the MRI scan, are ferritin (elevated in hemochromatosis), angiotensin converting enzyme (ACE) levels (often elevated in sarcoidosis), and human chorionic gonadotropin (often elevated in tumor of germ cell origin).
Hypopituitarism | Further investigations
Long-term follow up by specialists in endocrinology is generally needed for people with known hypopituitarism. Apart from ensuring the right treatment is being used and at the right doses, this also provides an opportunity to deal with new symptoms and to address complications of treatment. Difficult situations arise in deficiencies of the hypothalamus-pituitary-gonadal axis in people (both men and women) who experience infertility; infertility in hypopituitarism may be treated with subcutaneous infusions of FSH, human chorionic gonadotropin–which mimics the action of LH–and occasionally GnRH.
Hypopituitarism | Hormone replacement
Stimulation tests with GnRH are possible, but their use is not encouraged. For TSH, basal measurements are usually sufficient, as well as measurements of thyroxine to ensure that the pituitary is not simply suppressing TSH production in response to hyperthyroidism (an overactive thyroid gland). A stimulation test with thyrotropin-releasing hormone (TRH) is not regarded as useful. Prolactin can be measured by basal level, and is required for the interpretation of LH and FSH results in addition to the confirmation of hypopituitarism or diagnosis of a prolactin-secreting tumor.
Hypopituitarism | Basal tests
Unless the pituitary damage is being caused by a tumor that overproduces a particular hormone, it is the lack of pituitary hormones that leads to the symptoms described above, and an excess of a particular hormone would indicate the presence of a tumor. The exception to this rule is prolactin: if a tumor compresses the pituitary stalk, a decreased blood supply means that the lactotrope cells, which produce prolactin, are not receiving dopamine and therefore produce excess prolactin. Hence, mild elevations in prolactin are attributed to stalk compression. Very high prolactin levels, though, point more strongly towards a prolactinoma (prolactin-secreting tumor).
Hypopituitarism | Pathophysiology
General indications for pituitary surgery include patient drug intolerance, tumors resistant to medical therapy, patients who have persistent visual field defects in spite of medical treatment, and patients with large cystic or hemorrhagic tumors.
Galactorrhea hyperprolactinemia | Surgical care
Hypopituitarism is characterized by a decreased secretion of hormones released by the anterior pituitary. For example, hypo-secretion of GH prior to puberty can be a cause of dwarfism. In addition, secondary adrenal insufficiency can be caused by hypo-secretion of ACTH which, in turn, does not signal the adrenal cortex to produce a sufficient amount of cortisol. This is a life-threatening condition. Hypopituitarism could be caused by the destruction or removal of the anterior pituitary tissue through traumatic brain injury, tumor, tuberculosis, or syphilis, among other causes. This disorder used to be referred to as Simmonds' disease but now according to the Diseases Database it is called Sheehan syndrome.
Anterior pituitary | Decreased activity
If a genetic cause is suspected, genetic testing may be performed.
Hypopituitarism | Further investigations
Growth hormone deficiency is almost certain if all other pituitary tests are also abnormal, and insulin-like growth factor 1 (IGF-1) levels are decreased. If this is not the case, IGF-1 levels are poorly predictive of the presence of GH deficiency; stimulation testing with the insulin tolerance test is then required. This is performed by administering insulin to lower the blood sugar to a level below 2.2 mmol/l. Once this occurs, growth hormone levels are measured. If they are low despite the stimulatory effect of the low blood sugars, growth hormone deficiency is confirmed. The test is not without risks, especially in those prone to seizures or are known to have heart disease, and causes the unpleasant symptoms of hypoglycemia.
Hypopituitarism | Stimulation tests
This allowed the direct measurement of the hormones of the pituitary, which as a result of their low concentrations in blood had previously been hard to measure. Stimulation tests were developed in the 1960s, and in 1973 the triple bolus test was introduced, a test that combined stimulation testing with insulin, GnRH and TRH. Imaging of the pituitary, and therefore identification of tumors and other structural causes, improved radically with the introduction of computed tomography in the late 1970s and magnetic resonance imaging in the 1980s.
Hypopituitarism | History
Symptoms caused by hormone excess and associated mass effects include:
Hyperpituitarism | Symptoms and signs
Together, these cellular signals stimulate a group of cells from the oral cavity to form Rathke's pouch, which becomes independent of the nasal cavity and develops into the anterior pituitary; this process includes the suppression of production of a protein called Sonic hedgehog by the cells of Rathke's pouch. The cells then differentiate further into the various hormone-producing cells of the pituitary. This requires particular transcription factors that induce the expression of particular genes. Some of these transcription factors have been found to be deficient in some forms of rare combined pituitary hormone deficiencies (CPHD) in childhood. These are "HESX1", "PROP1", "POU1F1", "LHX3", "LHX4", "TBX19", "SOX2" and "SOX3".
Hypopituitarism | Pathophysiology
Health costs remain about double those of the normal population.
Hypopituitarism | Prognosis
Antidiuretic hormone (ADH) deficiency leads to the syndrome of "diabetes insipidus" (unrelated to diabetes mellitus): inability to concentrate the urine, leading to polyuria (production of large amounts of clear urine) that is low in solutes, dehydration and—in compensation—extreme thirst and constant need to drink (polydipsia), as well as hypernatremia (high sodium levels in the blood). ADH deficiency may be masked if there is ACTH deficiency, with symptoms only appearing when cortisol has been replaced. Oxytocin (OXT) deficiency generally causes few symptoms, as it is only required at the time of childbirth and breastfeeding.
Hypopituitarism | Posterior pituitary
Deficiency of all anterior pituitary hormones is more common than individual hormone deficiency. Deficiency of luteinizing hormone (LH) and follicle-stimulating hormone (FSH), together referred to as the gonadotropins, leads to different symptoms in men and women. Women experience oligo- or amenorrhea (infrequent/light or absent menstrual periods respectively) and infertility. Men lose facial, scrotal and trunk hair, as well as suffering decreased muscle mass and anemia. Both sexes may experience a decrease in libido and loss of sexual function, and have an increased risk of osteoporosis (bone fragility). Lack of LH/FSH in children is associated with delayed puberty. Growth hormone (GH) deficiency leads to a decrease in muscle mass, central obesity (increase in body fat around the waist) and impaired attention and memory.
Hypopituitarism | Anterior pituitary
Several studies have shown that hypopituitarism is associated with an increased risk of cardiovascular disease and some also an increased risk of death of about 50% to 150% the normal population. It has been difficult to establish which hormone deficiency is responsible for this risk, as almost all patients studied had growth hormone deficiency. The studies also do not answer the question as to whether the hypopituitarism itself causes the increased mortality, or whether some of the risk is to be attributed to the treatments, some of which (such as sex hormone supplementation) have a recognized adverse effect on cardiovascular risk.
Hypopituitarism | Prognosis
Hormonal disturbances may occur secondary to hypopituitarism, occurring immediately or years after injury in 10 to 15% of TBI patients. Development of diabetes insipidus or an electrolyte abnormality acutely after injury indicate need for endocrinologic work up. Signs and symptoms of hypopituitarism may develop and be screened for in adults with moderate TBI and in mild TBI with imaging abnormalities. Children with moderate to severe head injury may also develop hypopituitarism. Screening should take place 3 to 6 months, and 12 months after injury, but problems may occur more remotely. Cognitive deficits that can follow TBI include impaired attention; disrupted insight, judgement, and thought; reduced processing speed; distractibility; and deficits in executive functions such as abstract reasoning, planning, problem-solving, and multitasking.
Traumatic brain injury | Complications
The eponym "Simmonds' syndrome" is used infrequently for acquired hypopituitarism, especially when cachexia (general ill health and malnutrition) predominates. Most of the classic causes of hypopituitarism were described in the 20th century; the early 21st century saw the recognition of how common hypopituitarism could be in previous head injury victims. Until the 1950s, the diagnosis of pituitary disease remained based on clinical features and visual field examination, sometimes aided by pneumoencephalography and X-ray tomography. Nevertheless, the field of pituitary surgery developed during this time. The major breakthrough in diagnosis came with the discovery of radioimmunoassay by Rosalyn Yalow and Solomon Berson in the late 1950s.
Hypopituitarism | History
Symptoms of diabetes insipidus should prompt a formal fluid deprivation test to assess the body's response to dehydration, which normally causes concentration of the urine and increasing osmolarity of the blood. If these parameters are unchanged, desmopressin (an ADH analogue) is administered. If the urine then becomes concentrated and the blood osmolarity falls, there is a lack of ADH due to lack of pituitary function ("cranial diabetes insipidus"). In contrast, there is no change if the kidneys are unresponsive to ADH due to a different problem ("nephrogenic diabetes insipidus").
Hypopituitarism | Stimulation tests
Several hormone deficiencies associated with hypopituitarism may lead to secondary diseases. For instance, growth hormone deficiency is associated with obesity, raised cholesterol and the metabolic syndrome, and estradiol deficiency may lead to osteoporosis. While effective treatment of the underlying hormone deficiencies may improve these risks, it is often necessary to treat them directly.
Hypopituitarism | Complications
Levels of LH/FSH may be suppressed by a raised prolactin level, and are therefore not interpretable unless prolactin is low or normal. In men, the combination of low LH and FSH in combination with a low testosterone confirms LH/FSH deficiency; a high testosterone would indicate a source elsewhere in the body (such as a testosterone-secreting tumor). In women, the diagnosis of LH/FSH deficiency depends on whether the woman has been through the menopause. Before the menopause, abnormal menstrual periods together with low estradiol and LH/FSH levels confirm a pituitary problem; after the menopause (when LH/FSH levels are normally elevated and the ovaries produce less estradiol), inappropriately low LH/FSH alone is sufficient.
Hypopituitarism | Basal tests
For the diagnosis of hyperpituitarism it depends on the cell type(s) affected, clinical manifestations of hormone excess may include, gigantism or acromegaly, which can be identified by clinical and radiographic results. Cushing's disease diagnosis is done with a physical examination, laboratory tests and X rays of the pituitary glands (to locate tumors) For prolactinoma, diagnosis comes in the form of the measurement of serum prolactin levels and x-ray of pituitary gland.
Hyperpituitarism | Diagnosis
Pituitary tumors require treatment when they are causing specific symptoms, such as headaches, visual field defects or excessive hormone secretion. Transsphenoidal surgery (removal of the tumor by an operation through the nose and the sphenoidal sinuses) may, apart from addressing symptoms related to the tumor, also improve pituitary function, although the gland is sometimes damaged further as a result of the surgery. When the tumor is removed by craniotomy (opening the skull), recovery is less likely–but sometimes this is the only suitable way to approach the tumor. After surgery, it may take some time for hormone levels to change significantly.
Hypopituitarism | Underlying cause
Areas of lighter pigmentation can be indications of hypopigmentation. Biopsies and genetic information are also used to diagnose.
Hypopigmentation | Diagnosis
There are four categories of symptoms and signs. Most commonly, the initial symptoms are headaches and visual disturbances. Some symptoms are derived from the lesser functioning of the adenohypophyseal hormones. Of the adenohypophyseal hormones, the most frequently affected are corticotropes, lactotropes and gonadotropes, all which are found in the anterior pituitary. Polyuria is also a common symptom – which results in very dilute urine, as well as polydipsia which means having extreme thirst. Another symptom is hyperprolactinemia, which is when there are abnormally high prolactin levels in the blood. Usually, a mass will be found located on the sella turcica and loss of hormonal function.
Hypophysitis | Signs and symptoms
The pituitary gland is located at the base of the brain, and intimately connected with the hypothalamus. It consists of two lobes: the posterior pituitary, which consists of nervous tissue branching out of the hypothalamus, and the anterior pituitary, which consists of hormone-producing epithelium. The posterior pituitary secretes antidiuretic hormone, which regulates osmolarity of the blood, and oxytocin, which causes contractions of the uterus in childbirth and participates in breastfeeding. The pituitary develops in the third week of embryogenesis from interactions between the diencephalon part of the brain and the nasal cavity. The brain cells secrete FGF-8, Wnt5a and BMP-4, and the oral cavity BMP-2.
Hypopituitarism | Pathophysiology
Pituitary apoplexy is bleeding into or impaired blood supply of the pituitary gland. This usually occurs in the presence of a tumor of the pituitary, although in 80% of cases this has not been diagnosed previously. The most common initial symptom is a sudden headache, often associated with a rapidly worsening visual field defect or double vision caused by compression of nerves surrounding the gland. This is often followed by acute symptoms caused by lack of secretion of essential hormones, predominantly adrenal insufficiency. The diagnosis is achieved with magnetic resonance imaging and blood tests. Treatment is by the timely correction of hormone deficiencies.
Pituitary apoplexy | Introduction
Hypophysitis refers to an inflammation of the pituitary gland. Hypophysitis is rare and not fully understood.
Hypophysitis | Introduction
Alternative tests (such as the growth hormone releasing hormone stimulation test) are less useful, although a stimulation test with arginine may be used for diagnosis, especially in situations where an insulin tolerance test is thought to be too dangerous. If GH deficiency is suspected, and all other pituitary hormones are normal, two different stimulation tests are needed for confirmation. If morning cortisol levels are over 500 nmol/l, ACTH deficiency is unlikely, whereas a level less than 100 is indicative. Levels between 100-500 require a stimulation test. This, too, is done with the insulin tolerance test. A cortisol level above 500 after achieving a low blood sugar rules out ACTH deficiency, while lower levels confirm the diagnosis.
Hypopituitarism | Stimulation tests
Patients may present with features of hypocalcaemia including carpo-pedal muscular spasms, cramping, tetany, and if the calcium deficit is severe, generalized seizures. IQ is typically mildly depressed or unaffected. Additional characteristics include short stature, obesity, developmental delay, and calcification of the basal ganglia in the deep white matter of the brain. Type 1a Pseudohypoparathyroidism is clinically manifest by bone resorption with blunting of the fourth and fifth knuckles of the hand, most notable when the dorsum of the hand is viewed in closed fist position. This presentation is known as 'knuckle knuckle dimple dimple' sign (Archibald's sign). This is as opposed to Turner syndrome which is characterized by blunting of only the fourth knuckle, and Down syndrome, which is associated with a hypoplastic middle phalanx.
Pseudohypoparathyroidism | Presentation
The various signs and symptoms in Sheehan's syndrome are caused by damage to the pituitary, thereby causing a decrease in one or more of the hormones it normally secretes. Because the pituitary controls many glands in the endocrine system, partial or complete loss of a variety of functions may result. The most common initial symptoms of Sheehan's syndrome are agalactorrhea (absence of lactation) and/or difficulties with lactation. Many women also report amenorrhea or oligomenorrhea after delivery. In some cases, a woman with Sheehan syndrome is relatively asymptomatic; therefore, the diagnosis would not be made until years later, with features of hypopituitarism.
Sheehan's syndrome | Signs and symptoms
Hyponatremia, an unusually low level of sodium in the blood that may cause confusion and seizures, is found in 40% of cases. This may be caused by low cortisol levels or by inappropriate release of antidiuretic hormone (ADH) from the posterior pituitary. Several other hormonal deficiencies may develop in the subacute phase. 50% have a deficiency in thyroid-stimulating hormone (TSH), leading to hyposecretion of thyroid hormone by the thyroid gland and characteristic symptoms such as fatigue, weight gain, and cold intolerance. 75% develop a deficiency to gonadotropins (LH and FSH), which control the reproductive hormone glands. This leads to a disrupted menstrual cycle, infertility, and decreased libido.
Pituitary apoplexy | Endocrine dysfunction
The largest study to date followed over a thousand people for eight years; it showed an 87% increased risk of death compared to the normal population. Predictors of higher risk were: female sex, absence of treatment for sex hormone deficiency, younger age at the time of diagnosis, and a diagnosis of craniopharyngioma. Apart from cardiovascular disease, this study also showed an increased risk of death from lung disease. Quality of life may be significantly reduced, even in those people on optimum medical therapy. Many report both physical and psychological problems. It is likely that the commonly used replacement therapies do not completely mimic the natural hormone levels in the body.
Hypopituitarism | Prognosis
These mutations also lead to varying degrees of hypopituitarism.
Development of the endocrine system | Parathyroid glands
Underdevelopment of the pituitary gland in SOD leads to hypopituitarism, most commonly in the form of growth hormone deficiency.
Septo-optic dysplasia | Pituitary hormone abnormalities
In response to the releasing hormone rate, the anterior pituitary produces its hormones (TSH, ACTH, LH, FSH, GH) which in turn stimulate effector hormone glands in the body, while prolactin (PRL) acts directly on the breast gland. Once the effector glands produce sufficient hormones (thyroxine, cortisol, estradiol or testosterone and IGF-1), both the hypothalamus and the pituitary cells sense their abundance and reduce their secretion of stimulating hormones. The hormones of the posterior pituitary are produced in the hypothalamus and are carried by nerve endings to the posterior lobe; their feedback system is therefore located in the hypothalamus, but damage to the nerve endings would still lead to a deficiency in hormone release.
Hypopituitarism | Pathophysiology
The diagnosis of hypotransferrinemia is done via the following means to ascertain if an individual has the condition:
Hypotransferrinemia | Diagnosis
Retesting the pituitary hormone levels is therefore performed 2 to 3 months later. Prolactinomas may respond to dopamine agonist treatment–medication that mimics the action of dopamine on the lactrotrope cells, usually bromocriptine or cabergoline. This approach may improve pituitary hormone secretion in more than half the cases, and make supplementary treatment unnecessary. Other specific underlying causes are treated as normally. For example, hemochromatosis is treated by venesection, the regular removal of a fixed amount of blood. Eventually, this decreases the iron levels in the body and improves the function of the organs in which iron has accumulated.
Hypopituitarism | Underlying cause
There is only one study that has measured the prevalence (total number of cases in a population) and incidence (annual number of new cases) of hypopituitarism. This study was conducted in Northern Spain and used hospital records in a well-defined population. The study showed that 45.5 people out of 100,000 had been diagnosed with hypopituitarism, with 4.2 new cases per year. 61% were due to tumors of the pituitary gland, 9% due to other types of lesions, and 19% due to other causes; in 11% no cause could be identified. Recent studies have shown that people with a previous traumatic brain injury, spontaneous subarachnoid hemorrhage (a type of stroke) or radiation therapy involving the head have a higher risk of hypopituitarism.
Hypopituitarism | Epidemiology
Symptoms include weakness, hypoglycemia, weight loss and decreased axillary and pubic hair. It can be either isolated or part of a generalised pituitary dysfunction. It can be life-threatening if not recognised.
Adrenocorticotropic hormone deficiency | Presentation
Sheehan's syndrome, also known as postpartum pituitary gland necrosis, is hypopituitarism (decreased functioning of the pituitary gland), caused by ischemic necrosis due to blood loss and hypovolemic shock during and after childbirth.
Sheehan's syndrome | Introduction
Hypoproteinemia is often confirmed by testing for serum albumin and total protein levels.
Hypoproteinemia | Diagnosis
Examples of symptoms of hypogonadism include delayed, reduced, or absent puberty, low libido, and infertility.
Hypergonadotropic hypogonadism | Symptoms and signs
Prognosis for patients varies and is dependent on severity of the condition and how early the treatment is managed.
Hypoprothrombinemia | Prognosis
Chronic severe orthostatic hypotension may present as fluctuating cognition/delirium.
Orthostatic hypotension | Signs and symptoms
Conversely, acromegaly and gigantism are conditions of GH and IGF-1 excess usually due to a pituitary tumor, and are characterized by overgrowth and tall stature.
Hypothalamic–pituitary–somatotropic axis | Introduction
If large volumes of dilute urine are seen, this can be a warning sign that overcorrection is imminent in these individuals. Sodium deficit = (140 – serum sodium) x total body water Total body water = kilograms of body weight x 0.6
Hyponatremia | Treatment
It can be asymptomatic, but these symptoms may be present:
Hyperaldosteronism | Signs and symptoms
Lacking the sense of smell (anosmia) along with delayed puberty are strong clinical indications for Kallmann syndrome. Deficiencies in GnRH, the signalling hormone produced by the hypothalamus, can cause congenital malformations including cleft lip and scoliosis. The presence of neurological symptoms including headaches and visual disturbances suggest a brain disorder such as a brain tumor causing hypopituitarism. The presence of neurological symptoms in addition to lactation are signs of high prolactin levels and could indicate either a drug side effect or a prolactinoma.
Delayed puberty | Genetic or acquired defect of the hormonal pathway of puberty
These hypophysiotropic hormones stimulate or inhibit the release of hormones from the anterior pituitary. Further, anatomical evidence exists for bidirectional communication between the median eminence and the arcuate and ventromedial nucleus of the hypothalamus.
Median eminence | Physiology
In cases of endophthalmitis, one usually finds a history of recent intraocular surgery or penetrating ocular trauma. In some cases of endogenous endophthalmitis—particularly in immunocompromised patients or those with diabetes—the spread of infection may have been hematogenous (via the blood-stream). Endophthalmitis is usually accompanied by severe pain, loss of vision, and redness of the conjunctiva and the underlying episclera. Hypopyon can be present in endophthalmitis and should be looked for on examination by a slit lamp. It can first present with the 'black dot sign' (Martin-Farina sign) where patients may report a small area of loss of vision that resembles a black dot or 'fly'.
Endophthalmitis | Signs and symptoms
A similar stimulation test using corticotropin-releasing hormone (CRH) is not sensitive enough for the purposes of the investigation. If the insulin tolerance test yields an abnormal result, a further test measuring the response of the adrenal glands to synthetic ACTH (the ACTH stimulation test) can be performed to confirm the diagnosis. Stimulation testing with metyrapone is an alternative. Some suggest that an ACTH stimulation test is sufficient as first-line investigation, and that an insulin tolerance test is only needed if the ACTH test is equivocal. The insulin tolerance test is discouraged in children. None of the tests for ACTH deficiency are perfect, and further tests after a period of time may be needed if initial results are not conclusive.
Hypopituitarism | Stimulation tests
Hypoprolactinemia is a medical condition characterized by a deficiency in the serum levels of the hypothalamic-pituitary hormone prolactin.
Hypoprolactinemia | Introduction
Growth hormone deficiency has been reported in several individuals with 18p-, though not at the same frequency as in the distal 18q- population. Panhypopituitarism and hypothyroidism have each been diagnosed in a handful of individuals. Also, ketotic hypoglycemia has been reported in several individuals and usually presents itself around the age of three.
18p- | Endocrinology
The patients were all diagnosed at middle age. The symptoms were slowly and steadily progressive. Telangiectasias developed over the face, trunk and arms. Increased serum erythropoietin levels, eventually exceeding 5000 mU /ml, preceded the intrapulmonary shunting and the development of hypoxemia. Sampling of the perinephric fluid revealed a clear, serous fluid with low levels of protein, few leukocytes and no cholesterol or triglycerides. A monoclonal gammopathy was implicated in all patients tested. Spontaneous venous thromboses occurred in some patients, sometimes accompanied with spontaneous intracranial bleeding in the absence of blood vessels malformations.
TEMPI syndrome | Signs and symptoms
Hypophysectomies can be performed in three ways. These include transsphenoidal hypophysectomy, open craniotomy, and stereotactic radiosurgery. Each of these methods differ in the method in which the pituitary gland is removed.
Hypophysectomy | Methods of Hypophysectomy
As described above, orthostatic hypotension diagnosis is when there is a drop of greater than or equal to 20 mmHg or greater or equal to 10 mmHg in systolic and diastolic blood pressures, respectively within 3 minutes of standing. In the case of hypovolemia, there is also a compensatory rise in heart rate of greater than 15 beats/minute.
Orthostatic syncope | Signs and symptoms
In this case prompt medical action is required.
Vaginal hypoplasia | Signs and symptoms
hypopituitarism) or tertiary adrenal insufficiency (disease of the hypothalamus, with a decrease in the release of corticotropin releasing hormone (CRH)). Conversely, chronically elevated ACTH levels occur in primary adrenal insufficiency (e.g. Addison's disease) when adrenal gland production of cortisol is chronically deficient. In Cushing's disease a pituitary tumor is the cause of elevated ACTH (from the anterior pituitary) and an excess of cortisol (hypercortisolism) – this constellation of signs and symptoms is known as Cushing's syndrome.
Adrenocorticotropic hormone | Introduction
In a transsphenoidal hypophysectomy, the pituitary gland or section of the pituitary gland is removed through the sphenoid sinus and out through the nose.
Hypophysectomy | Transsphenoidal hypophysectomy
The prognosis for hypophysitis was variable for each individual. The depending factors for hypophysitis included the advancement of the mass on the sella turcica, percentage of fibrosis, and the body's response to corticosteroids. Through the use of corticosteroids, the vision defects tend to recover when the gland size began to decrease. The prognoses of the limited number of reported cases were usually good.
Hypophysitis | Prognosis
Hyperpituitarism is a condition due to the primary hypersecretion of pituitary hormones; it typically results from a pituitary adenoma. In children with hyperpituitarism, disruption of growth regulation is rare, either because of hormone hypersecretion or because of manifestations caused by local compression of the adenoma.
Hyperpituitarism | Introduction
The presentation of this disorder entails brain damage, neurological conditions, heart dysfunctions, and any kind of symptoms that arise on the grounds of iron oxidation within human cells caused by non-transferrin (protein) bound iron (NTBI).
Hypotransferrinemia | Symptoms and signs
The symptoms of hypogonadotrophic hypogonadism, a subtype of hypogonadism, include late, incomplete or lack of development at puberty, and sometimes short stature or the inability to smell; in females, a lack of breasts and menstrual periods, and in males a lack of sexual development, e.g., facial hair, penis and testes enlargement, deepening voice.
Hypogonadism | Hypogonadotrophic hypogonadism
It is recommended that magnetic resonance imaging (MRI) scan of the pituitary gland is performed if the diagnosis is suspected; this has a sensitivity of over 90% for detecting pituitary apoplexy; it may demonstrate infarction (tissue damage due to a decreased blood supply) or hemorrhage. Different MRI sequences can be used to establish when the apoplexy occurred, and the predominant form of damage (hemorrhage or infarction). If MRI is not suitable (e.g. due to claustrophobia or the presence of metal-containing implants), a computed tomography (CT) scan may demonstrate abnormalities in the pituitary gland, although it is less reliable. Many pituitary tumors (25%) are found to have areas of hemorrhagic infarction on MRI scans, but apoplexy is not said to exist unless it is accompanied by symptoms.
Pituitary apoplexy | Diagnosis
Over several years, the activity the HPG axis decreases and women are no longer fertile. Although males remain fertile until death, the activity of the HPG axis decreases. As males age, the testes begin to produce less testosterone, leading to a condition known as post-pubertal hypogonadism. The cause of the decreased testosterone is unclear and a current topic of research. Post-pubertal hypogonadism results in progressive muscle mass decrease, increase in visceral fat mass, loss of libido, impotence, decreased attention, increased risk of fractures, and abnormal sperm production.
Hypothalamic–pituitary–gonadal axis | Life cycle
growth of the frontal and prefrontal lobes is slightly decreased and b.the scores on the neuropsychological tests is decreased. Focal onset hemiconvulsions or generalised convulsions occur in nearly half of the seizures. These are usually shorter than the preceding autonomic manifestations but in a few cases a. they may be prolonged constituting convulsive status epilepticus or b. the preceding autonomic manifestations are brief and not apparent
Panayiotopoulos syndrome | Signs and symptoms
The use of the term hypogonadotropic relates to the fact that the hypogonadism found in HH is caused by a disruption in the production of the gonadotropin hormones normally released by the anterior pituitary gland known as luteinising hormone (LH) and follicle stimulating hormone (FSH). Failure in GnRH activity can otherwise be due to the absence of the GnRH releasing neurons inside the hypothalamus. HH can occur as an isolated condition with just the LH and FSH production being affected or it can occur in combined pituitary deficiency conditions. In the first 10 weeks of normal embryonic development, the GnRH releasing neurons migrate from their original source in the nasal region and end up inside the hypothalamus.
Kallmann syndrome | Pathophysiology
An adequate cortisol response is defined as a rise to greater than 550 nmol/L. Patients with impaired cortisol responses (less than 550 but greater than 400 nmol/L) may only need steroid cover for major illnesses or stresses. An adequate GH response occurs with an absolute response exceeding 20 mU/L.
Insulin tolerance test | Hypopituitarism
Type II: Symptoms are usually more capricious, but can include a variety of the symptoms described previously. Less severe cases of the disorder typically do not involve spontaneous bleeding.
Hypoprothrombinemia | Signs and symptoms
Hypophysectomy is the surgical removal of the hypophysis (pituitary gland). It is most commonly performed to treat tumors, especially craniopharyngioma tumors. Sometimes it is used to treat Cushing's syndrome due to pituitary adenoma or Simmond's disease It is also applied in neurosciences (in experiments with lab animals) to understand the functioning of hypophysis. There are various ways a hypophysectomy can be carried out. These methods include transsphenoidal hypophysectomy, open craniotomy, and stereotactic radiosurgery. Medications that are given as hormone replacement therapy following a complete hypophysectomy (removal of the pituitary gland) are often glucocorticoids. Secondary Addison's and hyperlipidemia can occur. Thyroid hormone is useful in controlling cholesterol metabolism that has been affected by pituitary deletion.
Hypophysectomy | Introduction
Orthographic projections:
Hypotenuse | Properties
Each transcription factor acts in particular groups of cells. Therefore, various genetic mutations are associated with specific hormone deficiencies. For instance, "POU1F1" (also known as Pit-1) mutations cause specific deficiencies in growth hormone, prolactin and TSH. In addition to the pituitary, some of the transcription factors are also required for the development of other organs; some of these mutations are therefore also associated with specific birth defects. Most of the hormones in the anterior pituitary are each part of an "axis" that is regulated by the hypothalamus. The hypothalamus secretes a number of releasing hormones, often according to a circadian rhythm, into blood vessels that supply the anterior pituitary; most of these are stimulatory (thyrotropin-releasing hormone, corticotropin-releasing hormone, gonadotropin-releasing hormone and growth hormone-releasing hormone), apart from dopamine, which suppresses prolactin production.
Hypopituitarism | Pathophysiology
Also, the pattern of secretion of growth hormone is sexually dimorphic; this is why in many species, adult males are visibly distinguishable from females.
Hypothalamus | Sexual dimorphism
Lymphocytic Infundibuloneurohypophysitis (LINH) occurs when the posterior pituitary is affected resulting in diabetes insipidus. Both LAH and LINH may also lead to symptoms of an intracranial mass such as headache or disturbance of vision, i.e. bitemporal hemianopia. The pituitary produces multiple hormones relating to various metabolic functions. Sufficiently low production of certain pituitary hormones can be fatal resulting in the failure of the thyroid or adrenal glands. It is estimated that, typically, it takes from 12 to 40 years for autoimmune destruction to present symptoms. However, there have been cases of isolated attacks as a result of drug reactions (i.e., use of blocking antibody ipilimumab) or idiopathic events that have presented symptoms which may disappear after relatively short term treatment (i.e., 1 year on corticoids or other immune suppressants).
Autoimmune hypophysitis | Signs and symptoms
A tilt table test may also be performed.
Orthostatic hypotension | Diagnosis
The symptoms of Leydig cell hypoplasia include pseudohermaphroditism, i.e., feminized, ambiguous, or relatively mildly underdeveloped (e.g., micropenis, severe hypospadias, and/or cryptorchidism [undescended testes]) external genitalia, a female gender identity or gender variance, hypergonadotropic hypogonadism (hypogonadism despite high levels of gonadotropins), delayed, impaired, or fully absent puberty with an associated reduction in or complete lack of development of secondary sexual characteristics (sexual infantilism), impaired fertility or complete sterility, tall stature (due to delayed epiphyseal closure), eunuchoid skeletal proportions, delayed or absent bone maturation, and osteoporosis.
Leydig cell hypoplasia | Symptoms and signs
Pituitary extracts may be administered to replace the missing hormones (hormonal replacement therapy) in patients with Froehlich syndrome. Tumors of the hypothalamus should be surgically removed if possible. Appetite may be very difficult to manage, although weight control depends on this.
Adiposogenital dystrophy | Treatment
There is a remarkable variety of symptoms that depends, largely, on the age of the patient at initial presentation, ranging from death "in utero" to relatively mild problems with dentition in adult life. Although several clinical sub-types of the disease have been characterized, based on the age at which skeletal lesions are discovered, the disease is best understood as a single continuous spectrum of severity.
Hypophosphatasia | Symptoms and signs
Professional guidelines recommend that if pituitary apoplexy is suspected or confirmed, the minimal blood tests performed should include a complete blood count, urea (a measure of renal function, usually performed together with creatinine), electrolytes (sodium and potassium), liver function tests, routine coagulation testing, and a hormonal panel including IGF-1, growth hormone, prolactin, luteinizing hormone, follicle-stimulating hormone, thyroid-stimulating hormone, thyroid hormone, and either testosterone in men or estradiol in women.
Pituitary apoplexy | Diagnosis
Hormonal stimulation tests of the pituitary have been reported to provoke episodes. Treatment of prolactinomas (pituitary adenomas that secrete prolactin) with dopamine agonist drugs, as well as withdrawal of such treatment, has been reported to precipitate apoplexy. Hemorrhage from a Rathke's cleft cyst, a remnant of Rathke's pouch that normally regresses after embryological development, may cause symptoms that are indistinguishable from pituitary apoplexy. Pituitary apoplexy is regarded by some as distinct from Sheehan's syndrome, where the pituitary undergoes infarction as a result of prolonged very low blood pressure, particularly when caused by bleeding after childbirth. This condition usually occurs in the absence of a tumor.
Pituitary apoplexy | Causes
Diagnosis typically occurs during the first 6 months of life due to characteristic neurological symptoms. These symptoms include muscle spasms, tetany, and seizures. Laboratory testing indicates hypomagnesemia (decreased serum magnesium levels), hypocalcemia (decreased serum calcium levels), and little to no measurable parathyroid hormone levels. Diagnosis is confirmed with these symptoms and can be further solidified with genetic sequencing of the TRPM6 gene.
Hypomagnesemia with secondary hypocalcemia | Diagnosis
The expression "glandula pituitaria" and its English equivalent "pituitary gland" can only be justified from a historical point of view. The inclusion of this synonym is merely justified by noting that the main term "hypophysis" is a much less popular term.
Pituitary gland | Pituitary gland
It is normally difficult to distinguish a case of Kallmann syndrome (KS)/hypogonadotropic hypogonadism (HH) from a straightforward constitutional delay of puberty. However, if puberty has not started by either age 14 (girls) or 15 (boys) years and one or more of the non-reproductive features mentioned below is present, then a referral to reproductive endocrinologist might be advisable. The features of KS and other forms of HH can be split into two different categories; "reproductive" and "non-reproductive".
Kallmann syndrome | Signs and symptoms
Lifelong hormone replacement therapy for the hormones that are missing. This may involve treatment with glucocorticoids. After hormone profiling, treatment with cortisol, ACTH, thyroid hormones, gonadotropins, and prolactin as seen in cases of hypopituitarism may occur.
Sheehan's syndrome | Treatment
If there are symptoms, people with empty sella syndrome can have headaches and vision loss. Additional symptoms would be associated with hypopituitarism. Additional symptoms are as follows:
Empty sella syndrome | Signs and symptoms