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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. 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.
Most pituitary hormones can be replaced indirectly by administering the products of the effector glands: hydrocortisone (cortisol) for adrenal insufficiency, levothyroxine for hypothyroidism, testosterone for male hypogonadism, and estradiol for female hypogonadism (usually with a progestogen to inhibit unwanted effects on the uterus). Growth hormone is available in synthetic form, but needs to be administered parenterally (by injection). Antidiuretic hormone can be replaced by desmopressin (DDAVP) tablets or nose spray. Generally, the lowest dose of the replacement medication is used to restore wellbeing and correct the deranged results, as excessive doses would cause side-effects or complications. Those requiring hydrocortisone are usually instructed to increase their dose in physically stressful events such as injury, hospitalization and dental work as these are times when the normal supplementary dose may be inadequate, putting the patient at risk of adrenal crisis.
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.
Life long hormone replacement therapy for the hormones that are missing.
GH treatment is not recommended for children who are not growing despite having normal levels of growth hormone, and in the UK it is not licensed for this use. Children requiring treatment usually receive daily injections of growth hormone. Most pediatric endocrinologists monitor growth and adjust dose every 3–6 months and many of these visits involve blood tests and x-rays. Treatment is usually extended as long as the child is growing, and lifelong continuation may be recommended for those most severely deficient. Nearly painless insulin syringes, pen injectors, or a needle-free delivery system reduce the discomfort. Injection sites include the biceps, thigh, buttocks, and stomach. Injection sites should be rotated daily to avoid lipoatrophy. Treatment is expensive, costing as much as US $10,000 to $40,000 a year in the USA.
Adding liothyronine (synthetic T) to levothyroxine has been suggested as a measure to provide better symptom control, but this has not been confirmed by studies. In 2007, the British Thyroid Association stated that combined T and T therapy carried a higher rate of side effects and no benefit over T alone. Similarly, American guidelines discourage combination therapy due to a lack of evidence, although they acknowledge that some people feel better when receiving combination treatment. Treatment with liothyronine alone has not received enough study to make a recommendation as to its use; due to its shorter half-life it needs to be taken more often.
People with hypothyroidism who do not feel well despite optimal levothyroxine dosing may request adjunctive treatment with liothyronine. A 2012 guideline from the European Thyroid Association recommends that support should be offered with regards to the chronic nature of the disease and that other causes of the symptoms should be excluded. Addition of liothyronine should be regarded as experimental, initially only for a trial period of 3 months, and in a set ratio to the current dose of levothyroxine. The guideline explicitly aims to enhance the safety of this approach and to counter its indiscriminate use.
GH deficiency is treated by replacing GH with daily injections under the skin or into muscle. Until 1985, growth hormone for treatment was obtained by extraction from human pituitary glands collected at autopsy. Since 1985, recombinant human growth hormone (rHGH) is a recombinant form of human GH produced by genetically engineered bacteria, manufactured by recombinant DNA technology. In both children and adults, costs of treatment in terms of money, effort, and the impact on day-to-day life, are substantial.
Myxedema coma or severe decompensated hypothyroidism usually requires admission to the intensive care, close observation and treatment of abnormalities in breathing, temperature control, blood pressure, and sodium levels. Mechanical ventilation may be required, as well as fluid replacement, vasopressor agents, careful rewarming, and corticosteroids (for possible adrenal insufficiency which can occur together with hypothyroidism). Careful correction of low sodium levels may be achieved with hypertonic saline solutions or vasopressin receptor antagonists. For rapid treatment of the hypothyroidism, levothyroxine or liothyronine may be administered intravenously, particularly if the level of consciousness is too low to be able to safely swallow medication. While administration through a nasogastric tube is possible, this may be unsafe and is discouraged.
Direct treatment is geared toward resolving hyperprolactinemic symptoms or reducing tumor size. Patients on medications that cause hyperprolactinaemia should have them withdrawn if possible. Patients with hypothyroidism should be given thyroid hormone replacement therapy. When symptoms are present, medical therapy is the treatment of choice. Patients with hyperprolactinemia and no symptoms (idiopathic or microprolactinoma) can be monitored without treatment. Consider treatment for women with amenorrhea. In addition, dual energy X-ray absorptiometry scanning should be considered to evaluate bone density. The persistent hypogonadism associated with hyperprolactinemia can lead to osteoporosis. Treatment significantly improves the patient's quality of life. If the goal is to treat hypogonadism only, patients with idiopathic hyperprolactinemia or microadenoma can be treated with estrogen replacement therapy and prolactin levels can be monitored. Radiation treatment is another option. However, the risk of hypopituitarism makes this a poor choice. It may be necessary for rapidly growing tumors, but its benefits in routine treatment have not been shown to outweigh the risks.
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.
The first-line treatment of Cushing's disease is surgical resection of ACTH-secreting pituitary adenoma; this surgery involves removal of the tumor via transsphenoidal surgery (TSS).
There are two possible options for access to sphenoidal sinus including of endonosal approach (through the nostril) or sublabial approach (through an incision under the upper lip); many factors such as the size of nostril, the size of the lesion, and the preferences of the surgeon cause the selection of one access route over the other.
Some tumors do not contain a discrete border between tumor and pituitary gland; therefore, careful sectioning through pituitary gland may be required to identify the location of tumor. The probability of successful resection is higher in patients where the tumor was identified at initial surgery in comparison to patients where no tumor was found initially; the overall remission rates in patients with microadenomas undergoing TSS are in range of 65%-90%, and the remission rate in patients with macroadenomas are lower than 65%. patients with persistent disease after initial surgery are treated with repeated pituitary surgery as soon as the active persistent disease is evident; however, reoperation has lower success rate and increases the risk of pituitary insufficiency.
Pituitary radiation therapy is another option for treatment of postoperative persisting hypercortisolemia following unsuccessful transsphenoidal surgery. External-beam pituitary RT is more effective treatment for pediatric CD in children with cure rates of 80%-88%. Hypopituitarism specifically growth hormone deficiency has been reported as the only most common late morbidity of this treatment; GHD has been reported in 36% and 68% of the patients undergoing post pituitary RT for Cushing's disease.
Bilateral adrenalectomy is another treatment which provides immediate reduction of cortisol level and control of hypercortisolism. However, it requires education of patients, because lifelong glucocorticoid and mineralocorticoid replacement therapy is needed for these patients. One of the major complications of this treatment is progression of Nelson's syndrome which is caused by enhance level of tumor growth and ACTH secretion post adrenalectomy in 8%-29% of patients with CD.
During post surgical recovery, patients collect 24-hour urine sample and blood sample for detecting the level of cortisol with the purpose of cure test; level of cortisol near the detection limit assay, corresponds to cure. Hormonal replacement such as steroid is given to patients because of steroid withdrawal. After the completion of collecting urine and blood samples, patients are asked to switch to glucocorticoid such as prednisone to decrease symptoms associated with adrenal withdrawal.
A study of 3,525 cases of TSS for Cushing's disease in the nationally representative
sample of US hospitals between 1993 and 2002 was conducted and revealed the following results: the in-hospital mortality rate was 0.7%; the complication rate was 42.1%. Diabetes insipidus (15%), fluid and electrolyte abnormalities (12.5%), and neurological deficits (5.6%) were the most common complications reported. The analyses of the study show that complications were more likely in patients with pre-operative comorbidities. Patients older than 64 years were more likely to have an adverse outcome and prolonged hospital stay. Women were 0.3 times less likely to have adverse outcomes in comparison to men.
The first priority in suspected or confirmed pituitary apoplexy is stabilization of the circulatory system. Cortisol deficiency can cause severe low blood pressure. Depending on the severity of the illness, admission to a high dependency unit (HDU) may be required.
Treatment for acute adrenal insufficiency requires the administration of intravenous saline or dextrose solution; volumes of over two liters may be required in an adult. This is followed by the administration of hydrocortisone, which is pharmaceutical grade cortisol, intravenously or into a muscle. The drug dexamethasone has similar properties, but its use is not recommended unless it is required to reduce swelling in the brain around the area of hemorrhage. Some are well enough not to require immediate cortisol replacement; in this case, blood levels of cortisol are determined at 9:00 AM (as cortisol levels vary over the day). A level below 550 nmol/l indicates a need for replacement.
The decision on whether to surgically decompress the pituitary gland is complex and mainly dependent on the severity of visual loss and visual field defects. If visual acuity is severely reduced, there are large or worsening visual field defects, or the level of consciousness falls consistently, professional guidelines recommend that surgery is performed. Most commonly, operations on the pituitary gland are performed through transsphenoidal surgery. In this procedure, surgical instruments are passed through the nose towards the sphenoid bone, which is opened to give access to the cavity that contains the pituitary gland. Surgery is most likely to improve vision if there was some remaining vision before surgery, and if surgery is undertaken within a week of the onset of symptoms.
Those with relatively mild visual field loss or double vision only may be managed conservatively, with close observation of the level of consciousness, visual fields, and results of routine blood tests. If there is any deterioration, or expected spontaneous improvement does not occur, surgical intervention may still be indicated. If the apoplexy occurred in a prolactin-secreting tumor, this may respond to dopamine agonist treatment.
After recovery, people who have had pituitary apoplexy require follow-up by an endocrinologist to monitor for long-term consequences. MRI scans are performed 3–6 months after the initial episode and subsequently on an annual basis. If after surgery some tumor tissue remains, this may respond to medication, further surgery, or radiation therapy with a "gamma knife".
There are no treatments which increase prolactin levels in humans. Treatment differs based on the reason for diagnosis. Women who are diagnosed with hypoprolactinemia following lactation failure are typically advised to formula feed, although treatment with metoclopramide has been shown to increase milk supply in clinical studies. For subfertility, treatment may include clomiphene citrate or gonadotropins.
Treatment options depend on the type of tumor and on its size:
- Prolactinomas are most often treated with cabergoline or quinagolide (both dopamine agonists), which decrease tumor size as well as alleviates symptoms, followed by serial imaging to detect any increase in size. Treatment where the tumor is large can be with radiation therapy or surgery, and patients generally respond well. Efforts have been made to use a progesterone antagonist for the treatment of prolactinomas, but so far have not proved successful.
- Somatotrophic adenomas respond to octreotide, a long-acting somatostatin analog, in many but not all cases according to a review of the medical literature. Unlike prolactinomas, thyrotrophic adenomas characteristically respond poorly to dopamine agonist treatment.
- Surgery is a common treatment for pituitary tumors. The normal approach is Trans-sphenoidal adenectomy, which usually can remove the tumor without affecting the brain or optic nerves.
- Danazol is a steroid compound that has been labelled as an "Anterior pituitary suppressant".
The goal of newborn screening programs is to detect and start treatment within the first 1–2 weeks of life. Treatment consists of a daily dose of thyroxine, available as a small tablet. The generic name is levothyroxine, and several brands are available. The tablet is crushed and given to the baby with a small amount of water or milk. The most commonly recommended dose range is 10-15 μg/kg daily, typically 12.5 to 37.5 or 44 μg.
Within a few weeks, the T and TSH levels are rechecked to confirm that they are being normalized by treatment. As the child grows up, these levels are checked regularly to maintain the right dose. The dose increases as the child grows.
Treatment is usually medication with dopamine agonists such as cabergoline, bromocriptine (often preferred when pregnancy is possible), and less frequently lisuride. A new drug in use is norprolac with the active ingredient quinagolide. Terguride is also used.
"Vitex agnus-castus" extract can be tried in cases of mild hyperprolactinaemia.
In a study of 1,034 symptomatic adults, Sheehan syndrome was found to be the sixth most frequent etiology of growth hormone deficiency, being responsible for 3.1% of cases (versus 53.9% due to a pituitary tumor).
Through multiple advancements within the medical field, care-givers have been able to stray away from utilizing bilateral adrenalectomy as the treatment for Cushing's disease. This has decreased the risk of patients presenting with Nelson's syndrome. Alternative treatments for Nelson's syndrome have been discovered. The most utilized technique for Nelson's syndrome has been transsphenoidal surgery. In addition, pharmacotherapy, radiotherapy, and radiosurgery have been utilized accompanying a surgical procedure. Pharmalogical drugs can also be given accompanying a transsphenoidal surgery including the following: pasireotide, temozolomide and octreotide. Within rats/mice, rosiglitazone has been an effective measure, however this has not been discovered in humans yet.
In larger case series, the mortality was 1.6% overall. In the group of patients who were unwell enough to require surgery, the mortality was 1.9%, with no deaths in those who could be treated conservatively.
After an episode of pituitary apoplexy, 80% of people develop hypopituitarism and require some form of hormone replacement therapy. The most common problem is growth hormone deficiency, which is often left untreated but may cause decreased muscle mass and strength, obesity and fatigue. 60–80% require hydrocortisone replacement (either permanently or when unwell), 50–60% need thyroid hormone replacement, and 60–80% of men require testosterone supplements. Finally, 10–25% develop diabetes insipidus, the inability to retain fluid in the kidneys due to a lack of the pituitary antidiuretic hormone. This may be treated with the drug desmopressin, which can be applied as a nose spray or taken by mouth.
Male primary or hypergonadogropic hypogonadism is often treated with testosterone replacement therapy if they are not trying to conceive. Adverse effects of testosterone replacement therapy include increased cardiovascular events (including strokes and heart attacks) and death. The Food and Drug Administration (FDA) stated in 2015 that neither the benefits nor the safety of testosterone have been established for low testosterone levels due to aging. The FDA has required that testosterone pharmaceutical labels include warning information about the possibility of an increased risk of heart attacks and stroke.
Commonly used testosterone replacement therapies include transdermal (through the skin) using a patch or gel, injections, or pellets. Oral testosterone is no longer used in the U.S. because it is broken down in the liver and rendered inactive; it also can cause severe liver damage. Like many hormonal therapies, changes take place over time. It may take as long as 2–3 months at optimum level to reduce the symptoms, particularly wordfinding and cognitive dysfunction. Testosterone levels in the blood should be evaluated to ensure the increase is adequate. Levels between 400 and 700 ng/dL are considered appropriate mid-dose levels. Treatment usually starts with 200 mg intramuscular testosterone, repeated every 14 days.
While historically, men with prostate cancer risk were warned against testosterone therapy, that has shown to be a myth.
Other side effects can include an elevation of the hematocrit to levels that require blood withdrawal (phlebotomy) to prevent complications from excessively thick blood. Gynecomastia (growth of breasts in men) sometimes occurs. Finally, some physicians worry that obstructive sleep apnea may worsen with testosterone therapy, and should be monitored.
Another treatment for hypogonadism is human chorionic gonadotropin (hCG). This stimulates the LH receptor, thereby promoting testosterone synthesis. This will not be effective in men who simply cannot make testosterone anymore (primary hypogonadism) and the failure of hCG therapy is further support for the existence of true testicular failure in a patient. It is particularly indicated in men with hypogonadism who wish to retain their fertility, as it does not suppress spermatogenesis like testosterone replacement therapy does.
For both men and women, an alternative to testosterone replacement is low-dose clomifene treatment, which can stimulate the body to naturally increase hormone levels while avoiding infertility and other side effects that can result from direct hormone replacement therapy. This therapy has only been shown helpful for men with secondary hypogonadism. Recent studies have shown it can be safe and effective monotherapy for up to 2 years in patients with intact testicular function and impaired function of the HPTA(http://www.nature.com/ijir/journal/v15/n3/full/3900981a.html). Clomifene blocks estrogen from binding to some estrogen receptors in the hypothalamus, thereby causing an increased release gNRH and subsequently LH from the pituitary. Clomifene is a Selective Estrogen Reuptake Modulator (SERM).
Generally clomifene does not have adverse effects at the doses used for this purpose. Clomifene at much higher doses is used to induce ovulation and has significant adverse effects in such a setting.
For women with hypogonadism, estradiol and progesterone are often replaced. Some types of fertility defects can be treated, others cannot. Some physicians also give testosterone to women, mainly to increase libido.
Common treatments for Nelson's syndrome include radiation or surgical procedure. Radiation allows for the limitation of the growth of the pituitary gland and the adenomas. If the adenomas start to affect the surrounding structures of the brain, then a micro-surgical technique can be adapted in order to remove the adenomas in a transsphenoidal (bone at base of the skull) process. Death may result with development of a locally aggressive pituitary tumor. However, does not commonly occur with pituitary diseases. In the rare case, ACTH-secreting tumors can become malignant. Morbidity from the disease can occur due to pituitary tissue compression or replacement, and compression of structures that surround the pituitary fossa. The tumor can also compress the optic apparatus, disturb cerebrospinal fluid flow, meningitis, and testicular enlargement in rare cases.
Most children born with congenital hypothyroidism and correctly treated with thyroxine grow and develop normally in all respects. Even most of those with athyreosis and undetectable T levels at birth develop with normal intelligence, although as a population academic performance tends to be below that of siblings and mild learning problems occur in some.
Congenital hypothyroidism is the most common preventable cause of intellectual disability. Few treatments in the practice of medicine provide as large a benefit for as small an effort.
The developmental quotient (DQ, as per Gesell Developmental Schedules) of children with hypothyroidism at age 24 months that have received treatment within the first 3 weeks of birth is summarised below:
Cushing's disease is a cause of Cushing's syndrome characterised by increased secretion of adrenocorticotropic hormone (ACTH) from the anterior pituitary (secondary hypercortisolism). This is most often as a result of a pituitary adenoma (specifically pituitary basophilism) or due to excess production of hypothalamus CRH (corticotropin releasing hormone) (tertiary hypercortisolism/hypercorticism) that stimulates the synthesis of cortisol by the adrenal glands. Pituitary adenomas are responsible for 80% of endogenous Cushing's syndrome, when excluding Cushing's syndrome from exogenously administered corticosteroids.
This should not be confused with ectopic Cushing syndrome or exogenous steroid use.
Acute adrenal insufficiency is a medical emergency and needs to be treated with injectable hydrocortisone and fluid support.
Growth hormone-releasing hormone (GHRH) is another releasing factor secreted by the hypothalamus. GHRH stimulates the pituitary gland to secrete growth hormone (GH), which has various effects on body growth and sexual development. Insufficient GH production may cause poor somatic growth, precocious puberty or gonadotropin deficiency, failure to initiate or complete puberty, and is often associated with rapid weight gain, low T, and low levels of sex hormones.
Hypothalamic disease is a disorder presenting primarily in the hypothalamus, which may be caused by damage resulting from malnutrition, including anorexia and bulimia eating disorders, genetic disorders, radiation, surgery, head trauma, lesion, tumour or other physical injury to the hypothalamus. The hypothalamus is the control center for several endocrine functions. Endocrine systems controlled by the hypothalamus are regulated by anti-diuretic hormone (ADH), corticotropin-releasing hormone, gonadotropin-releasing hormone, growth hormone-releasing hormone, oxytocin, all of which are secreted by the hypothalamus. Damage to the hypothalamus may impact any of these hormones and the related endocrine systems. Many of these hypothalamic hormones act on the pituitary gland. Hypothalamic disease therefore affects the functioning of the pituitary and the target organs controlled by the pituitary, including the adrenal glands, ovaries and testes, and the thyroid gland.
Numerous dysfunctions manifest as a result of hypothalamic disease. Damage to the hypothalamus may cause disruptions in body temperature regulation, growth, weight, sodium and water balance, milk production, emotions, and sleep cycles. Hypopituitarism, neurogenic diabetes insipidus, tertiary hypothyroidism, and developmental disorders are examples of precipitating conditions caused by hypothalamic disease.