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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.
Beta blockers, like Atenolol, are sometimes used to help suppress symptoms.
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.
The primary treatment of PPID is pergolide, a dopamine agonist that provides suppression to the pars intermedia in place of the dysfunctional hypothalamus. Horses should be reassessed in 30 days following the start of treatment, though evaluation of clinical signs and by baseline diagnostic testing, to ensure the appropriate dose is being prescribed. Results from that test dictate changes in dose. Horses that are responding to treatment should be retested every 6 months, including a test in the autumn when there is a seasonal increase in ACTH, to ensure their ACTH levels are appropriately suppressed during this time. Drug side effects include a transient decrease in appetite, which can be reduced by slowly increasing the dose to therapeutic levels, and by breaking up the daily dose into twice-daily administrations.
Attitude, activity levels, hyperglycemia, and increased drinking and urination are usually improved within 30 days of initiating treatment. Other clinical signs, such as hirsutism, potbellied appearance, muscle wasting, laminitic episodes, and increased predisposition to infection usually take between 30 days and 1 year to improve.
Cyproheptadine may be added to the treatment regime in horses that are inadequately responding to pergolide, but is usually only used in horses with advanced PPID on high doses of pergolide.
Treatment is directed towards (1) correcting hypotension, hypovolemia, electrolyte imbalances, and metabolic acidosis; (2) improving vascular integrity, and (3) providing an immediate source of glucocorticoids. Rapid correction of hypovolemia is the first priority.
Most patients show dramatic improvement within 24 to 48 hours of appropriate fluid and glucocorticoid therapy. Over the ensuing 2 to 4 days, a gradual transition from IV fluids to oral water and food is undertaken, and maintenance mineralocorticoid and glucocorticoid therapy is initiated. Failure to make this transition smoothly should raise suspicion of insufficient glucocorticoid supplementation, concurrent endocrinopathy (e.g. hypothyroidism), or cocurrent illness (especially renal damage).
The disorder is treated with vasopressin analogs such as Desmopressin. Nonetheless, many times desmopressin alone is not enough to bring under control all the symptoms, and another intervention must be implemented.
The main methods of management in involve exercise and diet change, in addition to treatment of PPID. The primary goal is reduction of weight in an obese animal. Diet changes include limiting pasture access and reducing or eliminating grain. Obese animals are often best maintained on a diet consisting ration balancer and hay, fed at 1.5% body weight and decreased if needed. Feed should be selected based on low non-structural carbohydrate levels. Hay NSC levels may be reduced by soaking it in cold water for 30 minutes.
Exercise is increased in non-laminitic horses. Animals resistant to weight loss, despite diet and exercise changes, can be placed on levothyroxine to increase metabolism. Metformin can also be used to reduce glucose absorption through the intestinal tract.
Aggressiveness of therapy depends on the clinical status of the patient and the nature of the insufficiency (glucocorticoid, mineralocorticoid, or both). Many dogs and cats with primary adrenal insufficiency are presented in Addisonian crisis and require immediate, aggressive therapy. In contrast, secondary insufficiency often has a chronic course.
Hypoadrenocorticism is treated with fludrocortisone (trade name Florinef) or a monthly injection of Percorten-V (desoxycorticosterone pivalate, DOCP) and prednisolone or Zycortal. Routine blood work is necessary in the initial stages until a maintenance dose is established. Most of the medications used in the therapy of hypoadrenocorticism cause excessive thirst and urination. It is absolutely vital to provide fresh drinking water for a canine suffering from this disorder.
If the owner knows about an upcoming stressful situation (shows, traveling etc.), the animals generally need an increased dose of prednisone to help deal with the added stress. Avoidance of stress is important for dogs with hypoadrenocorticism. Physical illness also stresses the body and may mean that the medication(s) need to be adjusted during this time. Most dogs with hypoadrenocorticism have an excellent prognosis after proper stabilization and treatment.
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.
How to manage SIADH depends on whether symptoms are present, the severity of the hyponatremia, and the duration. Management of SIADH includes:
- Removing the underlying cause when possible.
- Mild and asymptomatic hyponatremia is treated with adequate solute intake (including salt and protein) and fluid restriction starting at 500 ml per day of water with adjustments based on serum sodium levels. Long-term fluid restriction of 1,200–1,800 mL/day may maintain the person in a symptom free state.
- Moderate and symptomatic hyponatremia is treated by raising the serum sodium level by 0.5 to 1 mmol per liter per hour for a total of 8 mmol per liter during the first day with the use of furosemide and replacing sodium and potassium losses with 0.9% saline.
- For people with severe symptoms (severe confusion, convulsions, or coma) hypertonic saline (3%) 1–2 ml/kg IV in 3–4 h should be given.
- Drugs
- Demeclocycline can be used in chronic situations when fluid restrictions are difficult to maintain; demeclocycline is the most potent inhibitor of Vasopressin (ADH/AVP) action. However, demeclocycline has a 2–3 day delay in onset with extensive side effect profile, including skin photosensitivity, and nephrotoxicity.
- Urea: oral daily ingestion has shown favorable long-term results with protective effects in myelinosis and brain damage. Limitations noted to be undesirable taste and is contraindicated in people with cirrhosis to avoid initiation or potentiation of hepatic encephalopathy.
- Conivaptan – an antagonist of both V and V vasopressin receptors.
- Tolvaptan – an antagonist of the V vasopressin receptor.
Raising the serum sodium concentration too rapidly may cause central pontine myelinolysis. Avoid correction by more than 12 mEq/L/day. Initial treatment with hypertonic saline may abruptly lead to a rapid dilute diuresis and fall in ADH.
Treatment of HH may consist of administration of either a GnRH agonist or a gonadotropin formulation in the case of primary HH and treatment of the root cause (e.g., a tumor) of the symptoms in the case of secondary HH. Alternatively, hormone replacement therapy with androgens and estrogens in males and females, respectively, may be employed.
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.
Treatment modality depends on the cause. Tumors may be removed surgically, but pituitary stalk interruption may persist. Usually, replacement of those hormones that are reduced due to failed feedback control systems will be necessary.
Hypoaldosteronism may result in hyperkalemia and is the cause of 'type 4 renal tubular acidosis', sometimes referred to as hyperkalemic RTA or tubular hyperkalemia. However, the acidosis, if present, is often mild. It can also cause urinary sodium wasting, leading to volume depletion and hypotension.
When adrenal insufficiency develops rapidly, the amount of Na+ lost from the extracellular fluid exceeds the amount excreted in the urine, indicating that Na+ also must be entering cells. When the posterior pituitary is intact, salt loss exceeds water loss, and the plasma Na+ falls. However, the plasma volume also is reduced, resulting in hypotension, circulatory insufficiency, and, eventually, fatal shock. These changes can be prevented to a degree by increasing the dietary NaCl intake. Rats survive indefinitely on extra salt alone, but in dogs and most humans, the amount of supplementary salt needed is so large that it is almost impossible to prevent eventual collapse and death unless mineralocorticoid treatment is also instituted.
People affected by adipsia lack the ability to feel thirst, thus they often must be directed to drink. Adipsic persons may undergo training to learn when it is necessary that they drink water. Currently, there is no medicine available to treat adipsia. For people with adipsia because of hypothalamic damage, there is no surgical or medicinal option to fix the damage. In some cases where adipsia was caused by growths on thirst centers in the brain, surgical removal of the growths was successful in treating adipsia. Although adipsic persons must maintain a strict water intake schedule, their diets and participation in physical activities are not limited.
People affected by diabetes insipidus have the option of using the intranasal or oral hormone desmopressin acetate (DDAVP), which is molecularly similar enough to vasopressin to perform its function. In this case, desmopressin helps the kidneys to promote reabsorption of water. Some doctors have reported success in treating psychogenic adipsic patients with electroconvulsive therapy, although the results are mixed and the reason for its success is still unknown. Additionally, some patients who do not successfully complete behavioral therapy may require a nasogastric tube in order to maintain healthy levels of fluids.
Desmopressin will be ineffective in nephrogenic DI which is treated by reversing the underlying cause (if possible) and replacing the free water deficit. The diuretic hydrochlorothiazide (a thiazide diuretic) or indomethacin can be used to create mild hypovolemia which encourages salt and water uptake in proximal tubule and thus improve nephrogenic diabetes insipidus. Amiloride has additional benefit of blocking Na uptake. Thiazide diuretics are sometimes combined with amiloride to prevent hypokalemia. It seems paradoxical to treat an extreme diuresis with a diuretic, and the exact mechanism of action is unknown but the thiazide diuretics will decrease distal convoluted tubule reabsorption of sodium and water, thereby causing diuresis. This decreases plasma volume, thus lowering the glomerular filtration rate and enhancing the absorption of sodium and water in the proximal nephron. Less fluid reaches the distal nephron, so overall fluid conservation is obtained.
Lithium-induced nephrogenic DI may be effectively managed with the administration of amiloride, a potassium-sparing diuretic often used in conjunction with thiazide or loop diuretics. Clinicians have been aware of lithium toxicity for many years, and traditionally have administered thiazide diuretics for lithium-induced polyuria and nephrogenic diabetes insipidus. However, amiloride has recently been shown to be a successful treatment for this condition.
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.
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.
Central DI and gestational DI respond to desmopressin which is given as intranasal or oral tablets. Carbamazepine, an anticonvulsive medication, has also had some success in this type of DI. Also, gestational DI tends to abate on its own four to six weeks following labor, though some women may develop it again in subsequent pregnancies. In dipsogenic DI, desmopressin is not usually an option.
Treatments vary based on the underlying condition. Key issues are problems of surgical correction if appropriate and oestrogen therapy if oestrogen levels are low. For those who do not plan to have biological children, treatment may be unnecessary if the underlying cause of the amenorrhoea is not threatening to their health. However, in the case of athletic amenorrhoea, deficiencies in estrogen and leptin often simultaneously result in bone loss, potentially leading to osteoporosis.
"Athletic" amenorrhoea which is part of the female athlete triad is treated by eating more and decreasing the amount and intensity of exercise. If the underlying cause is the athlete triad then a multidisciplinary treatment including monitoring from a physician, dietitian, and mental health counselor is recommended, along with support from family, friends, and coaches. Although oral contraceptives can causes menses to return, oral contraceptives should not be the initial treatment as they can mask the underlying problem and allow other effects of the eating disorder, like osteoporosis, continue to develop. Weight recovery, or increased rest does not always catalyze the return of a menses. Recommencement of ovulation suggests a dependency on a whole network of neurotransmitters and hormones, altered in response to the initial triggers of secondary amenorrhoea. To treat drug-induced amenorrhoea, stopping the medication on the advice of a doctor is a usual course of action.
Looking at Hypothalamic amenorrhoea, studies have provided that the administration of a selective serotonin reuptake inhibitor (SSRI) might correct abnormalities of Functional Hypothalamic Amenorrhoea (FHA) related to the condition of stress-related amenorrhoea. This involves the repair of the PI3K signaling pathway, which facilitates the integration of metabolic and neural signals regulating gonadotropin releasing hormone (GnRH)/luteinizing hormone (LH). In other words, it regulates the neuronal activity and expression of neuropeptide systems that promote GnRH release. However, SSRI therapy represents a possible hormonal solution to just one hormonal condition of hypothalamic amenorrhoea. Furthermore, because the condition involves the inter workings of many different neurotransmitters, much research is still to be done on presenting hormonal treatment that would counteract the hormonal affects.
As for physiological treatments to hypothalamic amenorrhoea, injections of metreleptin (r-metHuLeptin) have been tested as treatment to oestrogen deficiency resulting from low gonadotropins and other neuroendocrine defects such as low concentrations of thyroid and IGF-1. R-metHuLeptin has appeared effective in restoring defects in the hypothalamic-pituitary-gonadal axis and improving reproductive, thyroid, and IGF hormones, as well as bone formation, thus curing the amenorrhoea and infertility. However, it has not proved effective in restoring of cortisol and adrenocorticotropin levels, or bone resorption.
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.
The best diagnostic tool to confirm adrenal insufficiency is the ACTH stimulation test; however, if a patient is suspected to be suffering from an acute adrenal crisis, immediate treatment with IV corticosteroids is imperative and should not be delayed for any testing, as the patient's health can deteriorate rapidly and result in death without replacing the corticosteroids.
Dexamethasone should be used as the corticosteroid if the plan is to do the ACTH stimulation test at a later time as it is the only corticosteroid that will not affect the test results.
If not performed during crisis, then labs to be run should include: random cortisol, serum ACTH, aldosterone, renin, potassium and sodium. A CT of the adrenal glands can be used to check for structural abnormalities of the adrenal glands. An MRI of the pituitary can be used to check for structural abnormalities of the pituitary. However, in order to check the functionality of the Hypothalamic Pituitary Adrenal (HPA) Axis the entire axis must be tested by way of ACTH stimulation test, CRH stimulation test and perhaps an Insulin Tolerance Test (ITT). In order to check for Addison’s Disease, the auto-immune type of primary adrenal insufficiency, labs should be drawn to check 21-hydroxylase autoantibodies.
Treatment for KS and other forms of HH can be divided into hormone replacement therapy and fertility treatments.
The aim for hormone replacement therapy (HRT) for both men and women is to ensure that the level of circulating hormones (testosterone for men and oestrogen/progesterone for women) is at the normal physiological level for the age of the patient. At first the treatment will produce most of the physical and psychological changes seen at puberty, with the major exception that there will be no testicular development in men and no ovulation in women.
After the optimum physical development has been reached HRT for men will continue to ensure that the normal androgen function is maintained; such as libido, muscle development, energy levels, hair growth, and sexual function. In women, a variety of types of HRT will either give a menstruation cycle or not as preferred by the patient. HRT is very important in both men and women to maintain bone density and to reduce the risk of early onset osteoporosis.
The fertility treatments used for both men and women would still include hormone replacement in their action.
There are a range of different preparations available for HRT for both men and women; a lot of these, especially those for women are the same used for standard HRT protocols used when hormone levels fall in later life or after the menopause.
For males with KS / CHH the types of delivery method available include daily patches, daily gel use, daily capsules, sub cutaneous or intramuscular injections or six monthly implants. Different formulations of testosterone are used to ensure both the anabolic and androgenic effects of testosterone are achieved.
Testosterone undecanoate is commonly used worldwide, though less so in the US, for treating male KS / CHH patients and has proved to be effective in maintaining good testosterone levels with an increased injection period of up to 12 weeks.
The precise treatment method used and interval between injections will vary from patient to patient and may need to be adjusted to maintain a physiological normal level of testosterone over a longer period of time to prevent the mood swings or adverse effects that can occur if testosterone levels are too high or low. Some treatments may work better with some patients than others so it might be a case of personal choice as which one to use.
As an alternative human chorionic gonadotrophin (hCG) can also be used to stimulate natural testosterone production. It acts in the same way as LH; stimulating the Leydig cells in the testes to produce testosterone. hCG can be used as pre-cursor to male fertility treatments but it can be used in isolation just for testosterone production.
There are no specialist HRT treatments available just for women with KS/HH but there are multitude of different HRT products on the market including oral contraceptives and standard post-menopause products. Pills are popular but patches are also available. It may take some trial and error to find the appropriate HRT for the patient depending on how her body reacts to the particular HRT. Specialist medical advice will be required to ensure the correct levels of oestrogen and progesterone are maintained each month, depending on whether the patient requires continuous HRT (no-bleed) or a withdrawal option to create a "menstrual" type bleed. This withdrawal bleed can be monthly or over longer time periods depending on the type of medication used.