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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.
Thyroid hormone resistance syndrome is rare, incidence is variously quoted as 1 in 50,000 or 1 in 40,000 live births. More than 1000 individuals have been identified with thyroid hormone resistance, of which 85% had thyroid hormone beta receptor mutation.
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.
Beta blockers, like Atenolol, are sometimes used to help suppress symptoms.
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).
The primary current medical treatment of acromegaly is to use somatostatin analogues – octreotide (Sandostatin) or lanreotide (Somatuline).
These somatostatin analogues are synthetic forms of a brain hormone, somatostatin, which stops GH production. The long-acting forms of these drugs must be injected every 2 to 4 weeks for effective treatment. Most patients with acromegaly respond to this medication. In many patients, GH levels fall within one hour and headaches improve within minutes after the injection. Octreotide and lanreotide are effective for long-term treatment. Octreotide and lanreotide have also been used successfully to treat patients with acromegaly caused by non-pituitary tumors.
Somatostatin analogues are also sometimes used to shrink large tumors before surgery.
Because octreotide inhibits gastrointestinal and pancreatic function, long-term use causes digestive problems such as loose stools, nausea, and gas in one third of patients. In addition, approximately 25 percent of patients develop gallstones, which are usually asymptomatic. In some cases, octreotide treatment can cause diabetes due to the fact that somatostatin and its analogues can inhibit the release of insulin.
For those who are unresponsive to somatostatin analogues, or for whom they are otherwise contraindicated, it is possible to treat using one of the dopamine agonists, bromocriptine or cabergoline. As tablets rather than injections, they cost considerably less. These drugs can also be used as an adjunct to somatostatin analogue therapy. They are most effective in those whose pituitary tumours cosecrete prolactin. Side effects of these dopamine agonists include gastrointestinal upset, nausea, vomiting, light-headedness when standing, and nasal congestion. These side effects can be reduced or eliminated if medication is started at a very low dose at bedtime, taken with food, and gradually increased to the full therapeutic dose. However, bromocriptine lowers GH and IGF-1 levels and reduces tumor size in fewer than half of patients with acromegaly. Some patients report improvement in their symptoms although their GH and IGF-1 levels still are elevated.
Treatment (for hyperpituitarism) in the case of prolactinoma consists of long-term medical management. Dopamine agonists are strong suppressors of PRL secretion and establish normal gonadal function. It also inhibits tumor cell replication (in some cases causes tumor shrinkage) Treatment for gigantism begins with establishing target goals for IGF-1, transsphenoidal surgery (somatostatin receptor ligands- preoperatively) and postoperative imaging assessment. For Cushing's disease there is surgery to extract the tumor; after surgery, the gland may slowly start to work again, though not always.
Life long hormone replacement therapy for the hormones that are missing.
Dopamine is the chemical that normally inhibits prolactin secretion, so doctors may treat prolactinoma with bromocriptine, cabergoline or Quinagolide drugs that act like dopamine. This type of drug is called a dopamine agonist. These drugs shrink the tumor and return prolactin levels to normal in approximately 80% of patients. Both have been approved by the Food and Drug Administration for the treatment of hyperprolactinemia. Bromocriptine is associated with side-effects such as nausea and dizziness and hypotension in patients with already low blood pressure readings. To avoid these side-effects, it is important for bromocriptine treatment to start slowly.
Bromocriptine treatment should not be interrupted without consulting a qualified endocrinologist. Prolactin levels often rise again in most people when the drug is discontinued. In some, however, prolactin levels remain normal, so the doctor may suggest reducing or discontinuing treatment every two years on a trial basis. Recent studies have shown increased success in remission of prolactin levels after discontinuation, in patients having been treated for at least 2 years prior to cessation of bromocriptine treatment.
Cabergoline is also associated with side-effects such as nausea and dizziness, but these may be less common and less severe than with bromocriptine. However, people with low blood pressure should use caution when starting cabergoline treatment, as the long half-life of the drug (4–7 days) may inadvertently affect their ability to keep their blood pressure within normal limits, creating intense discomfort, dizziness, and even fainting upon standing and walking until the single first dose clears from their system. As with bromocriptine therapy, side-effects may be avoided or minimized if treatment is started slowly. If a patient's prolactin level remains normal for 6 months, a doctor may consider stopping treatment. Cabergoline should not be interrupted without consulting a qualified endocrinologist.
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.
The goal of treatment is to return prolactin secretion to normal, reduce tumor size, correct any visual abnormalities, and restore normal pituitary function. As mentioned above, the impact of stress should be ruled out before the diagnosis of prolactinoma is given. Exercise can significantly reduce stress and, thereby, prolactin levels. In the case of very large tumors, only partial reduction of the prolactin levels may be possible.
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.
Treatment for Addison's disease involves replacing the missing cortisol, sometimes in the form of hydrocortisone tablets, or prednisone tablets in a dosing regimen that mimics the physiological concentrations of cortisol. Alternatively, one-quarter as much prednisolone may be used for equal glucocorticoid effect as hydrocortisone. Treatment is usually lifelong. In addition, many patients require fludrocortisone as replacement for the missing aldosterone.
People with Addison's are often advised to carry information on them (e.g., in the form of a MedicAlert bracelet or information card) for the attention of emergency medical services personnel who might need to attend to their needs. It is also recommended that a needle, syringe, and injectable form of cortisol be carried for emergencies. People with Addison's disease are advised to increase their medication during periods of illness or when undergoing surgery or dental treatment. Immediate medical attention is needed when severe infections, vomiting, or diarrhea occur, as these conditions can precipitate an Addisonian crisis. A patient who is vomiting may require injections of hydrocortisone instead.
For more information on the form in horses, see pituitary pars intermedia dysfunction.
Most Cushing's syndrome cases are caused by corticosteroid medications, such as those used for asthma, arthritis, eczema and other inflammatory conditions. Consequently, most patients are effectively treated by carefully tapering off (and eventually stopping) the medication that causes the symptoms.
If an adrenal adenoma is identified, it may be removed by surgery. An ACTH-secreting corticotrophic pituitary adenoma should be removed after diagnosis. Regardless of the adenoma's location, most patients require steroid replacement postoperatively at least in the interim, as long-term suppression of pituitary ACTH and normal adrenal tissue does not recover immediately. Clearly, if both adrenals are removed, replacement with hydrocortisone or prednisolone is imperative.
In those patients not suited for or unwilling to undergo surgery, several drugs have been found to inhibit cortisol synthesis (e.g. ketoconazole, metyrapone) but they are of limited efficacy. Mifepristone is a powerful glucocorticoid type II receptor antagonist and, since it does not interfere with normal cortisol homeostatis type I receptor transmission, may be especially useful for treating the cognitive effects of Cushing's syndrome. However, the medication faces considerable controversy due to its use as an abortifacient. In February 2012, the FDA approved mifepristone to control high blood sugar levels (hyperglycemia) in adult patients who are not candidates for surgery, or who did not respond to prior surgery, with the warning that mifepristone should never be used by pregnant women.
Removal of the adrenals in the absence of a known tumor is occasionally performed to eliminate the production of excess cortisol. In some occasions, this removes negative feedback from a previously occult pituitary adenoma, which starts growing rapidly and produces extreme levels of ACTH, leading to hyperpigmentation. This clinical situation is known as Nelson's syndrome.
Standard therapy involves intravenous injections of glucocorticoids and large volumes of intravenous saline solution with dextrose (glucose). This treatment usually brings rapid improvement. If intravenous access is not immediately available, intramuscular injection of glucocorticoids can be used. When the patient can take fluids and medications by mouth, the amount of glucocorticoids is decreased until a maintenance dose is reached. If aldosterone is deficient, maintenance therapy also includes oral doses of fludrocortisone acetate.
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.
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.
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.
Treatment may consist of hormone replacement therapy with androgens in either sex. Alternatively, gonadotropin-releasing hormone (GnRH)/GnRH agonists or gonadotropins may be given (in the case of "hypogonadotropic" hypoandrogenism). 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.
Drug induced (iatrogenic) hypoadrenocorticism is caused during abrupt cessation of a steroid medication. During steroid treatment, the adrenal glands do not function fully. The body senses the levels of the exogenous steroids in the system and therefore does not signal for additional production. The usual protocol for stopping steroid medications is not to eliminate them suddenly, but to withdraw from them gradually in a "tapering off" process, which allows the production to adjust to normal. If steroids are abruptly withdrawn, the dormant adrenal glands may not able to reactivate, and the body will need to have its adrenal glucocorticoid hormones replaced by medication.
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.
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 of HH is usually with hormone replacement therapy, consisting of androgen and estrogen administration in males and females, respectively.