Made by DATEXIS (Data Science and Text-based Information Systems) at Beuth University of Applied Sciences Berlin
Deep Learning Technology: Sebastian Arnold, Betty van Aken, Paul Grundmann, Felix A. Gers and Alexander Löser. Learning Contextualized Document Representations for Healthcare Answer Retrieval. The Web Conference 2020 (WWW'20)
Funded by The Federal Ministry for Economic Affairs and Energy; Grant: 01MD19013D, Smart-MD Project, Digital Technologies
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.
Beta blockers, like Atenolol, are sometimes used to help suppress symptoms.
Many of the common symptoms of hyperthyroidism such as palpitations, trembling, and anxiety are mediated by increases in beta-adrenergic receptors on cell surfaces. Beta blockers, typically used to treat high blood pressure, are a class of drugs that offset this effect, reducing rapid pulse associated with the sensation of palpitations, and decreasing tremor and anxiety. Thus, a patient suffering from hyperthyroidism can often obtain immediate temporary relief until the hyperthyroidism can be characterized with the Radioiodine test noted above and more permanent treatment take place. Note that these drugs do not treat hyperthyroidism or any of its long-term effects if left untreated, but, rather, they treat or reduce only symptoms of the condition.
Some minimal effect on thyroid hormone production however also comes with Propranolol - which has two roles in the treatment of hyperthyroidism, determined by the different isomers of propranolol. L-propranolol causes beta-blockade, thus treating the symptoms associated with hyperthyroidism such as tremor, palpitations, anxiety, and heat intolerance. D-propranolol inhibits thyroxine deiodinase, thereby blocking the conversion of T to T, providing some though minimal therapeutic effect. Other beta-blockers are used to treat only the symptoms associated with hyperthyroidism. Propranolol in the UK, and metoprolol in the US, are most frequently used to augment treatment for hyperthyroid patients.
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.
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.
Levothyroxine is a stereoisomer of thyroxine (T4) which is degraded much more slowly and can be administered once daily in patients with hypothyroidism. Natural thyroid hormone from pigs is sometimes also used, especially for people who cannot tolerate the synthetic version. Hyperthyroidism caused by Graves' disease may be treated with the thioamide drugs propylthiouracil, carbimazole or methimazole, or rarely with Lugol's solution. Additionally, hyperthyroidism and thyroid tumors may be treated with radioactive iodine. Ethanol injections for the treatment of recurrent thyroid cysts and metastatic thyroid cancer in lymph nodes can also be an alternative to surgery.
Surgery (thyroidectomy to remove the whole thyroid or a part of it) is not extensively used because most common forms of hyperthyroidism are quite effectively treated by the radioactive iodine method, and because there is a risk of also removing the parathyroid glands, and of cutting the recurrent laryngeal nerve, making swallowing difficult, and even simply generalized staphylococcal infection as with any major surgery. Some people with Graves' may opt for surgical intervention. This includes those that cannot tolerate medicines for one reason or another, people that are allergic to iodine, or people that refuse radioiodine.
If people have toxic nodules treatments typically include either removal or injection of the nodule with alcohol.
Thyroid surgery is performed for a variety of reasons. A nodule or lobe of the thyroid is sometimes removed for biopsy or because of the presence of an autonomously functioning adenoma causing hyperthyroidism. A large majority of the thyroid may be removed ("subtotal thyroidectomy)" to treat the hyperthyroidism of Graves' disease, or to remove a goiter that is unsightly or impinges on vital structures.
A complete thyroidectomy of the entire thyroid, including associated lymph nodes, is the preferred treatment for thyroid cancer. Removal of the bulk of the thyroid gland usually produces hypothyroidism unless the person takes thyroid hormone replacement. Consequently, individuals who have undergone a total thyroidectomy are typically placed on thyroid hormone replacement (e.g. Levothyroxine) for the remainder of their lives. Higher than normal doses are often administered to prevent recurrence.
If the thyroid gland must be removed surgically, care must be taken to avoid damage to adjacent structures, the parathyroid glands and the recurrent laryngeal nerve. Both are susceptible to accidental removal and/or injury during thyroid surgery.
The parathyroid glands produce parathyroid hormone (PTH), a hormone needed to maintain adequate amounts of calcium in the blood. Removal results in hypoparathyroidism and a need for supplemental calcium and vitamin D each day. In the event that the blood supply to any one of the parathyroid glands is endangered through surgery, the parathyroid gland(s) involved may be re-implanted in surrounding muscle tissue.
The recurrent laryngeal nerves provide motor control for all external muscles of the larynx except for the cricothyroid muscle, which also runs along the posterior thyroid. Accidental laceration of either of the two or both recurrent laryngeal nerves may cause paralysis of the vocal cords and their associated muscles, changing the voice quality.
The main strategies for the management of thyroid storm are reducing production and release of thyroid hormone, reducing the effects of thyroid hormone on tissues, replacing fluid losses, and controlling temperature. Thyroid storm requires prompt treatment and hospitalization. Often, admission to the intensive care unit is needed.
Iodine
Guidelines recommend the administration of inorganic iodide (potassium iodide or Lugol's iodine) to reduce the synthesis and release of thyroid hormone. Iodine reduces the synthesis of thyroid hormone via the Wolf-Chaikoff effect. Some guidelines recommend that iodine be administered after antithyroid medications are started, because iodine is also a substrate for the synthesis of thyroid hormone, and may worsen hyperthyroidism if administered without antithyroid medications.
Antithyroid Medications
Antithyroid drugs (propylthiouracil or methimazole) are used to reduce the synthesis and release of thyroid hormone. Propylthiouracil is preferred over methimazole due to its additional effects on reducing peripheral conversion of T4 to T3, however both are commonly used.
Beta Blockers
The administration of beta-1-selective beta blockers (e.g. propranolol) is recommended to reduce the effect of circulating thyroid hormone on end organs. In addition, propanolol at high doses also reduces peripheral conversion of T4 to T3, which is the more active form of thyroid hormone. Although previously unselective beta blockers (e.g., propranolol) have been suggested to be beneficial due to their inhibitory effects on peripheral deiodinases recent research suggests them to be associated with increased mortality. Therefore, cardioselective beta blockers may be favourable.
Corticosteroids
High levels of thyroid hormone result in a hypermetabolic state, which can result in increased breakdown of cortisol, a hormone produced by the adrenal gland. This results in a state of relative adrenal insufficiency, in which the amount of cortisol is not sufficient. Guidelines recommend that corticosteroids (hydrocortisone and dexamethasone are preferred over prednisolone or methylprednisolone) be administered to all patients with thyroid storm. However, doses should be altered for each individual patient to ensure that the relative adrenal insufficiency is adequately treated while minimizing the risk of side effects.
Supportive Measures
In high fever, temperature control is achieved with fever reducers such as paracetamol/acetaminophen and external cooling measures (cool blankets, ice packs). Dehydration, which occurs due to fluid loss from sweating, diarrhea, and vomiting, is treated with frequent fluid replacement. In severe cases, mechanical ventilation may be necessary. Any suspected underlying cause is also addressed.
Toxic multinodular goiter can be treated with antithyroid medications such as propylthiouracil or methimazole, radioactive iodine, or with surgery.
Another treatment option is injection of ethanol into the nodules.
Severe hypocalcaemia, a potentially life-threatening condition, is treated as soon as possible with intravenous calcium (e.g. as calcium gluconate). Generally, a central venous catheter is recommended, as the calcium can irritate peripheral veins and cause phlebitis. In the event of a life-threatening attack of low calcium levels or tetany (prolonged muscle contractions), calcium is administered by intravenous (IV) infusion. Precautions are taken to prevent seizures or larynx spasms. The heart is monitored for abnormal rhythms until the person is stable. When the life-threatening attack has been controlled, treatment continues with medicine taken by mouth as often as four times a day.
Long-term treatment of hypoparathyroidism is with vitamin D analogs and calcium supplementation, but may be ineffective in some due to potential renal damage. The N-terminal fragment of parathyroid hormone (PTH 1-34) has full biological activity. The use of pump delivery of synthetic PTH 1-34 provides the closest approach to physiologic PTH replacement therapy. Injections of recombinant human parathyroid hormone are available as treatment in those with low blood calcium levels.
Treatment of Graves' disease includes antithyroid drugs which reduce the production of thyroid hormone; radioiodine (radioactive iodine I-131); and thyroidectomy (surgical excision of the gland). As operating on a frankly hyperthyroid patient is dangerous, prior to thyroidectomy, preoperative treatment with antithyroid drugs is given to render the patient "euthyroid" ("i.e." normothyroid). Each of these treatments has advantages and disadvantages. No one treatment approach is considered the best for everyone.
Treatment with antithyroid medications must be given for six months to two years to be effective. Even then, upon cessation of the drugs, the hyperthyroid state may recur. The risk of recurrence is about 40–50%, and lifelong treatment with antithyroid drugs carries some side effects such as agranulocytosis and liver disease. Side effects of the antithyroid medications include a potentially fatal reduction in the level of white blood cells. Therapy with radioiodine is the most common treatment in the United States, while antithyroid drugs and/or thyroidectomy are used more often in Europe, Japan, and most of the rest of the world.
β-Blockers (such as propranolol) may be used to inhibit the sympathetic nervous system symptoms of tachycardia and nausea until such time as antithyroid treatments start to take effect. Pure β-blockers do not inhibit lid-retraction in the eyes, which is mediated by alpha adrenergic receptors.
Levothyroxine is a stereoisomer of thyroxine which is degraded much slower and can be administered once daily in patients with hypothyroidism.
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.
Ideally a woman who is known to have hyperthyroidism should seek pre-pregnancy advice, although as yet there is no evidence for its benefit. Appropriate education should allay fears that are commonly present in these women. She should be referred for specialist care for frequent checking of her thyroid status, thyroid antibody evaluation and close monitoring of her medication needs. Medical therapy with anti-thyroid medications is the treatment of choice for hyperthyroidism in pregnancy.Methimazole and propylthiouracil (PTU) are effective in preventing pregnancy complications by hyperthyroidism. Surgery is considered for patients who suffer severe adverse reactions to anti-thyroid drugs and this is best performed in the second trimester of pregnancy. Radioactive iodine is absolutely contraindicated in pregnancy and the puerperium. If a woman is already receiving carbimazole, a change to propylthiouracil (PTU) is recommended but this should be changed back to carbimazole after the first trimester. This is because carbimazole can rarely be associated with skin and also mid line defects in the fetus but PTU long term also can cause liver side effects in the adult. Carbimazole and PTU are both secreted in breast milk but evidence suggests that antithyroid drugs are safe during lactation. There are no adverse effects on IQ or psychomotor development in children whose mothers have received antithyroid drugs in pregnancy.
Current guidelines suggest that a pregnant patient should be on PTU during the first trimester of pregnancy due to lower tetragenic effect and then be switched to methimazole during the second and third trimester due to lower liver dysfunction side effects.
The main antithyroid drugs are carbimazole (in the UK), methimazole (in the US), and propylthiouracil/PTU. These drugs block the binding of iodine and coupling of iodotyrosines. The most dangerous side effect is agranulocytosis (1/250, more in PTU). Others include granulocytopenia (dose-dependent, which improves on cessation of the drug) and aplastic anemia. Patients on these medications should see a doctor if they develop sore throat or fever. The most common side effects are rash and peripheral neuritis. These drugs also cross the placenta and are secreted in breast milk. Lugol's iodine may be used to block hormone synthesis before surgery.
A randomized control trial testing single-dose treatment for Graves' found methimazole achieved euthyroid state more effectively after 12 weeks than did propylthyouracil (77.1% on methimazole 15 mg vs 19.4% in the propylthiouracil 150 mg groups).
No difference in outcome was shown for adding thyroxine to antithyroid medication and continuing thyroxine versus placebo after antithyroid medication withdrawal. However, two markers were found that can help predict the risk of recurrence. These two markers are a positive TSHr antibody (TSHR-Ab) and smoking. A positive TSHR-Ab at the end of antithyroid drug treatment increases the risk of recurrence to 90% (sensitivity 39%, specificity 98%), a negative TSHR-Ab at the end of antithyroid drug treatment is associated with a 78% chance of remaining in remission. Smoking was shown to have an impact independent to a positive TSHR-Ab.
In endocrinology, medical emergencies include diabetic ketoacidosis, hyperosmolar hyperglycemic state, hypoglycemic coma, acute adrenocortical insufficiency, phaeochromocytoma crisis, hypercalcemic crisis, thyroid storm, myxoedema coma and pituitary apoplexy.
Emergencies arising from decompensated pheochromocytomas or parathyroid adenomas are sometimes referred for emergency resection when aggressive medical therapies fail to control the patient's state, however the surgical risks are significant, especially blood pressure lability and the possibility of cardiovascular collapse after resection (due to a brutal drop in respectively catecholamines and calcium, which must be compensated with gradual normalization). It remains debated when emergency surgery is appropriate as opposed to urgent or elective surgery after continued attempts to stabilize the patient, notably in view of newer and more efficient medications and protocols.
Goitre is treated according to the cause. If the thyroid gland is producing too much T3 and T4, radioactive iodine is given to the patient to shrink the gland. If goitre is caused by iodine deficiency, small doses of iodide in the form of Lugol's Iodine or KI solution are given. If the goitre is associated with an underactive thyroid, thyroid supplements are used as treatment. In extreme cases, a partial or complete thyroidectomy is required.
Treatment for TM is typically done with the collaboration of many medical specialists. Usually a neuromuscular specialist, an endocrinologist, a surgeon, and an ophthalmologist will combine their efforts to successfully treat patients with TM. If a patient develops significant to severe muscle degradation as a result of TM, a physical therapist may be consulted for rehabilitation.
Since excess thyroxine leads to onset of TM, the overall goal of treatment is to reduce to overproduction of thyroxine from the thyroid gland and restore normal thyroid homeostasis. This can be accomplished three ways including using medication, radiation, and surgery.
The first choice involves using medications to alleviate the symptoms and reverse the damage by blocking the production of thyroxine from the thyroid gland. Beta-blockers are used to alleviate the symptoms associated with TM. But beta-blockers do not reduce the damage done by excess thyroxine. Medications such as propylthiouracil and methimazole are administered to block the release of thyroxine from the thyroid and to block the damage thyroxine inflicts on muscle fiber tissue.
One treatment option is the use of radioactive iodine which directly destroys the overactive thyroid gland. The thyroid gland naturally uses iodine to produce thyroxine and other hormones. It cannot distinguish between normal iodine and the radioactive version. Administering the radioactive isotope causes the thyroid to take in the lethal iodine and quickly radiation destroys it. Typically overproduction of thyroxine using radio-iodine is blocked with one dose. The drawback to this treatment is the thyroid gland is completely destroyed and patients often develop hypothyroidism. Some do so only a few months after treatment while others may not be affected for 20–30 years. Hypothyroidism patients must begin a lifelong regimen of thyroid replacement hormones. While the onset of hypothyroidism is most common with radio-iodine treatment, the condition has been observed in patients treated with medication series and surgery.
The last option for TM treatment includes surgical removal of portions of the thyroid which can also be performed to restore thyroid homeostasis. This treatment option usually is done when overproduction of TM is caused by multinodular goiters. Since these goiters enlarge the thyroid and can cause the patient to become physically disfigured surgical treatment can alleviate both the aesthetic and physiological effects simultaneously.
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".
An alternative using high intensity focused ultrasound or HIFU has recently proved its effectiveness in treating benign thyroid nodules. This method is noninvasive, without general anesthesia and is performed in an ambulatory setting. Ultrasound waves are focused and produce heat enabling to destroy thyroid nodules.
Focused ultrasounds have been used to treat other benign tumors, such as breast fibroadenomas and fibroid disease in the uterus.
Treatment of a thyroid nodule depends on many things including size of the nodule, age of the patient, the type of thyroid cancer, and whether or not it has spread to other tissues in the body.
If the nodule is benign, patients may receive thyroxine therapy to suppress thyroid-stimulating hormone and should be reevaluated in 6 months. However, if the benign nodule is inhibiting the patient's normal functions of life; such as breathing, speaking, or swallowing, the thyroid may need to be removed.
Sometimes only part of the thyroid is removed in an attempt to avoid causing hypothyroidism. There's still a risk of hypothyroidism though, as the remaining thyroid tissue may not be able to produce enough hormones in the long-run.
If the nodule is malignant or has indeterminate cytologic features, it may require surgery. A thyroidectomy is a medium risk surgery that can result complications if not performed correctly. Problems with the voice, nerve or muscular damage, or bleeding from a lacerated blood vessel are rare but serious complications that may occur. After removing the thyroid, the patient must be supplied with a replacement hormone for the rest of their life. This is commonly a daily oral medication prescribed by their endocrinologist.
Radioactive iodine-131 is used in patients with papillary or follicular thyroid cancer for ablation of residual thyroid tissue after surgery and for the treatment of thyroid cancer. Patients with medullary, anaplastic, and most Hurthle cell cancers do not benefit from this therapy. External irradiation may be used when the cancer is unresectable, when it recurs after resection, or to relieve pain from bone metastasis.
Hypothyroidism caused by Hashimoto's thyroiditis is treated with thyroid hormone replacement agents such as levothyroxine, triiodothyronine or desiccated thyroid extract. A tablet taken once a day generally keeps the thyroid hormone levels normal. In most cases, the treatment needs to be taken for the rest of the person's life. In the event that hypothyroidism is caused by Hashimoto's thyroiditis, it may be recommended that the TSH levels be kept under 3.0 mIU/L.
Several trials investigated a possible therapy for ESS. However, they yielded inconsistent and partly contradictory results. This may be caused by the fact that the investigated populations were too heterogeneous in the lack of a consistent definition of "non-thyroid illness syndrome".
Modern theories regard the TACITUS syndrome as an adaptive and therefore possibly beneficial response of thyroid homeostasis. Their proponents are therefore reserved with respect to substitutive treatment.