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To minimise the risk of this condition developing from its most common cause, overly rapid reversal of hyponatremia, the hyponatremia should be corrected at a rate not exceeding 10 mmol/L/24 h or 0.5 mEq/L/h; or 18 m/Eq/L/48hrs; thus avoiding demyelination. No large clinical trials have been performed to examine the efficacy of therapeutic re-lowering of serum sodium, or other interventions sometimes advocated such as steroids or plasma exchange.
Alcoholic patients should receive vitamin supplementation and a formal evaluation of their nutritional status.
Once osmotic demyelination has begun, there is no cure or specific treatment. Care is mainly supportive. Alcoholics are usually given vitamins to correct for other deficiencies. The favourable factors contributing to the good outcome in CPM without hyponatremia were: concurrent treatment of all electrolyte disturbances, early Intensive Care Unit involvement at the advent of respiratory complications, early introduction of feeding including thiamine supplements with close monitoring of the electrolyte changes and input.
Research has led to improved outcomes. Animal studies suggest that inositol reduces the severity of osmotic demyelination syndrome if given before attempting to correct chronic hyponatraemia. Further study is required before using inositol in humans for this purpose.
A number of pharmaceuticals may be used in an attempt to bring the polydipsia under control, including:
- Atypical antipsychotics, such as clozapine, olanzapine and risperidone
- Demeclocycline, a tetracycline antibiotic, which is effective due to the side effect of inducing nephrogenic diabetes insipidus. Demeclocycline is used for cases of psychogenic polydipsia, including those with nocturnal enuresis (bed-wetting). Its mechanism of action involves direct inhibition of vasopressin at the DCTs, thus reducing urine concentration.
There are a number of emerging pharmaceutical treatments for psychogenic polydipsia, although these need further investigation:
- ACE Inhibitors, such as enalapril
- Clonidine, an alpha-2 adrenergic agonist
- Irbesartan, an angiotensin II receptor antagonist
- Propranolol, a sympatholytic beta blocker
- Vasopressin receptor antagonists, such as conivaptan
- Acetazolamide, a carbonic anhydrase inhibitor
Lithium was previously used for treatment of PPD as a direct competitive ADH agonist, but is now generally avoided due to its toxic effects on the thyroid and kidneys.
It is important to note that the majority of psychotropic drugs (and a good many of other classes) can cause dry mouth as a side effect, but this is not to be confused with true polydipsia in which a dangerous drop in serum sodium will be seen.
As with all cases of hyponatremia, extreme caution must be taken to avoid the fatal consequences of rapidly correcting electrolytes (e.g. Central pontine myelinolysis, edema). Special considerations with the treatment of potomania are needed. Because this could be a chronic condition, low sodium may be normal for the patient, so an especially careful correction is warranted. It is also very important to note that due to the normal kidney function, and lack of other intrinsic or toxic cause of the electrolyte disturbance, restoration of dietary solutes will correct the electrolytes to normal serum levels. This again must be done with caution.
Behavioural treatments may involve the use of a token economy to provide positive reinforcement to desirable behaviour. Furthermore, cognitive therapy techniques can be used to address the thought patterns that lead to compulsive drinking behaviour. Success has been seen in trials of this technique, with emphasis on the development of coping techniques (e.g. taking small sips of water, having ice cubes instead of drinks) in addition to challenging delusions leading to excessive drinking.
Psychogenic polydipsia often leads to institutionalisation of mentally ill patients, since it is difficult to manage in the community. Most studies of behavioural treatments occur in institutional settings and require close monitoring of the patient and a large degree of time commitment from staff.
Treatment of any kind of complex visual hallucination requires an understanding of the different pathologies in order to correctly diagnose and treat. If a person is taking a pro-hallucinogenic medication, the first step is to stop taking it. Sometimes improvement will occur spontaneously and pharmacotherapy is not necessary. While there is not a lot of evidence of effective pharmacological treatment, antipsychotics and anticonvulsants have been used in some cases to control hallucinations. Since peduncular hallucinosis occurs due to an excess of serotonin, modern antipsychotics are used to block both dopamine and serotonin receptors, preventing the overstimulation of the lateral geniculate nucleus. The drug generically called carbamazepine increases GABA, which prevents the LGN from firing, thereby increasing the inhibition of the LGN. Regular antipsychotics as well as antidepressants can also be helpful in reducing or eliminating peduncular hallucinosis.
More invasive treatments include corrective surgery such as cataract surgery, laser photocoagulation of the retina, and use of optical correcting devices. Tumor removal can also help to relieve compression in the brain, which can decrease or eliminate peduncular hallucinosis. Some hallucinations may be due to underlying cardiovascular disease, so in these cases the appropriate treatment includes control of hypertension and diabetes. As described, the type of treatment varies widely depending on the causation behind the complex visual hallucinations.
Though traditionally, the prognosis is considered poor, a good functional recovery is possible. All patients at risk of developing refeeding syndrome should have their electrolytes closely monitored, including sodium, potassium, magnesium, glucose and phosphate.
Recent data indicate that the prognosis of critically ill patients may even be better than what is generally considered, despite severe initial clinical manifestations and a tendency by the intensivists to underestimate a possible favorable evolution.
While some patients die, most survive and of the survivors, approximately one-third recover; one-third are disabled but are able to live independently; one-third are severely disabled. Permanent disabilities range from minor tremors and ataxia to signs of severe brain damage, such as spastic quadriparesis and locked-in syndrome. Some improvements may be seen over the course of the first several months after the condition stabilizes.
The degree of recovery depends on the extent of the original axonal damage.
Options include:
- 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/or 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.
- Severe hyponatremia or severe symptoms (confusion, convulsions, or coma): consider hypertonic saline (3%) 1–2 ml/kg IV in 3–4 h. Hypertonic saline may lead to a rapid dilute diuresis and fall in the serum sodium. It should not be used in those with an expanded extracellular fluid volume.
American and European guidelines come to different conclusions regarding the use of medications. In the United States they are recommended in those with SIADH, cirrhosis, or heart failure who fail limiting fluid intact. In Europe they are not generally recommended.
There is tentative evidence that vasopressin receptor antagonists (vaptans), such as conivaptan, may be slightly more effective than fluid restriction in those with high volume or normal volume hyponatremia. They should not be used in people with low volume. Their use in SIADH is unclear.
Demeclocycline, while sometimes used for SIADH, has significant side effects including potential kidney problems and sun sensitivity. In many people it has no benefit while in others it can result in overcorrection and high blood sodium levels.
Daily use of urea by mouth, while not commonly used due to the taste, has tentative evidence in SIADH. It, however, is not available in many areas of the world.
Neither a standard treatment nor a cure is available. Stimulation of muscle reflexes with electrodes (NMES) has been known to help patients regain some muscle function. Other courses of treatment are often symptomatic. Assistive computer interface technologies, such as Dasher, or OptiKey, combined with eye tracking, may be used to help a LIS survivor communicate with their environment in a better way.
CNS depression is treated within a hospital setting by maintaining breathing and circulation. Individuals with reduced breathing may be given supplemental oxygen, while individuals who are not breathing can be ventilated with bag valve mask ventilation or by mechanical ventilation with a respirator. Sympathomimetic drugs may be used to attempt to stimulate cardiac output in order to maintain circulation. CNS Depression caused by certain drugs may respond to treatment with an antidote.
There are two antidotes that are frequently used in the hospital setting and these are Naloxone and Flumazenil. Naloxone is an opioid antagonist and reverses the central nervous depressive effects seen in opioid overdose. In the setting of a colonoscopy, Naloxone is rarely administered but when it is administered, its half life is shorter than some common opioid agonists. Therefore, the patient may still exhibit central nervous system depression after Naloxone has been cleared. Typically, Naloxone is administered in short intervals with relatively small doses in order to prevent the occurrence of withdrawal, pain, and sympathetic nervous system activation. Flumazenil is a benzodiazepine antagonists and blocks the binding of benzodiazepines to GABAa. Similarly to Naloxone, Flumazenil has a short half life, and this needs to be taken into account because the patient may exhibit central nervous depression after the antidote has been cleared. Benzodiazepines are used in the treatment of seizures and subsequently, the administration of Flumazenil may result in seizures. Therefore, slow administration of Flumazenil is necessary to prevent the occurrence of a seizure. These agents are rarely used in the setting of a colonoscopy as 98.8% of colonoscopies use sedatives but only 0.8% of them result in the administration of one of these antidotes. Even if they are rarely used in colonoscopies they are important in preventing the patient from entering a coma or developing respiratory depression when sedatives are not properly dosed. Outside of the colonoscopy setting, these agents are used for other procedures and in the case of drug overdose.
It is extremely rare for any significant motor function to return. The majority of locked-in syndrome patients do not regain motor control, but devices are available to help patients communicate. However, some people with the condition continue to live much longer, while in exceptional cases, like that of Kerry Pink and Kate Allatt, a full spontaneous recovery may be achieved.
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 typically involves improving the patient's quality of life. This is accomplished through the management of symptoms or slowing the rate of demyelination. Treatment can include medication, lifestyle changes (i.e. quit smoking, adjusting daily schedules to include rest periods and dietary changes), counselling, relaxation, physical exercise, patient education and, in some cases, deep brain thalamic stimulation (in the case of tremors). The progressive phase of MS appears driven by the innate immune system, which will directly contribute to the neurodegenerative changes that occur in progressive MS. Until now, there are no therapies that specifically target innate immune cells in MS. As the role of innate immunity in MS becomes better defined, it may be possible to better treat MS by targeting the innate immune system.
Treatments are patient-specific and depend on the symptoms that present with the disorder, as well as the progression of the condition.
The current treatments for CCAS focus on relieving the symptoms. One treatment is a cognitive-behavioral therapy (CBT) technique that involves making the patient aware of his or hers cognitive problems. For example, many CCAS patients struggle with multitasking. With CBT, the patient would have to be aware of this problem and focus on just one task at a time. This technique is also used to relieve some motor symptoms. In a case study with a patient who had a stroke and developed CCAS, improvements in mental function and attention were achieved through reality orientation therapy and attention process training. Reality orientation therapy consists of continually exposing the patient to stimuli of past events, such as photos. Attention process training consists of visual and auditory tasks that have been shown to improve attention. The patient struggled in applying these skills to “real-life” situations. It was the help of his family at home that significantly helped him regain his ability to perform activities of daily living. The family would motivate the patient to perform basic tasks and made a regular schedule for him to follow.
Transcranial magnetic stimulation (TMS) has also been proposed to be a possible treatment of psychiatric disorders of the cerebellum. One study used TMS on the vermis of patients with schizophrenia. After stimulation, the patients showed increased happiness, alertness and energy, and decreased sadness. Neuropsychological testing post-stimulation showed improvements in working memory, attention, and visual spatial skill. Another possible method of treatment for CCAS is doing exercises that are used to relieve the motor symptoms. These physical exercises have been shown to also help with the cognitive symptoms.
Medications that help relieve deficits in traumatic brain injuries in adults have been proposed as candidates to treat CCAS. Bromocriptine, a direct D2 agonist, has been shown to help with deficits in executive function and spatial learning abilities. Methylphendiate has been shown to help with deficits in attention and inhibition. Neither of these drugs has yet been tested on a CCAS population. It may also be that some of the symptoms of CCAS improve over time without any formal treatment. In the original report of CCAS, four patients with CCAS were re-examined one to nine months after their initial neuropsychological evaluation. Three of the patients showed improvement in deficits without any kind of formal treatment, though executive function was still found to be one standard deviation below average. In one patient, the deficits worsened over time. This patient had cerebellar atrophy and worsened in visual spatial abilities, concept formation, and verbal memory. It should be noted that none of these treatments were tested on a large enough sample to determine if they would help with the general CCAS population. Further research needs to be done on treatments for CCAS.
Dextromethorphan hydrobromide is a generic drug that affects the signals in the brain that trigger the cough reflex. It is generally used as a cough suppressant, although it can sometimes be used, medicinally, as a pain reliever, and is also used as a recreational drug. "Dextromethorphan (DM) is a sigma-1 receptor agonist and an uncompetitive NMDA receptor antagonist."
Quinidine sulfate affects the way the heart beats, and is generally used in people with certain heart rhythm disorders. It is also used to treat malaria. Quinidine sulfate, as a metabolic inhibitor, "increases plasma levels of dextromethorphan by competitively inhibiting cytochrome P450 2D6, which catalyzes a major biotransformation pathway for dextromethorphan," enabling therapeutic dextromethorphan concentrations.
Nuedexta is a patented combination of these two generic drugs, and is the first FDA-approved drug for the treatment of PBA, approved on October 29, 2010. In December 2007, clinical study information for Nuedexta was first submitted to ClinicalTrials.gov, (a Web-based resource maintained by the National Library of Medicine (NLM) at the National Institutes of Health (NIH)). Sponsored by Avanir Pharmaceuticals, (with brief title, "Safety and Efficacy of AVP-923 in PBA Patients With ALS or MS"), the study was assigned NCT Number NCT00573443. Final updates and verifications occurred in June 2013 on the ClinicalTrials.gov site.
For this multicenter study, the "Objectives...[were] to evaluate the safety, tolerability, and efficacy of two different doses of AVP-923 [Dextromethorphan/quinidine combination]...when compared to placebo." The conditions and results of that study are as follows:
Other studies have confirmed the results of NCT00573443, but, "The mechanism by which dextromethorphan exerts therapeutic effects in patients with pseudobulbar affect is unknown."
Conventional radiotherapy, limited to the involved area of tumour, is the mainstay of treatment for DIPG. A total radiation dosage ranging from 5400 to 6000 cGy, administered in daily fractions of 150 to 200 cGy over 6 weeks, is standard. Hyperfractionated (twice-daily) radiotherapy was used previously to deliver higher radiation dosages, but did not lead to improved survival. Radiosurgery (e.g., gamma knife or cyberknife) has no role in the treatment of DIPG.
Amphetamine is a stimulant that has been found to improve both physical and cognitive performance. Amphetamine blocks the reuptake of dopamine and norepinephrine, which delays the onset of fatigue by increasing the amount of dopamine, despite the concurrent increase in norepinephrine, in the central nervous system. Amphetamine is a widely used substance among collegiate athletes for its performance enhancing qualities, as it can improve muscle strength, reaction time, acceleration, anaerobic exercise performance, power output at fixed levels of perceived exertion, and endurance.
Methylphenidate has also been shown to increase exercise performance in time to fatigue and time trial studies.
Caffeine is the most widely consumed stimulant in North America. In small doses, caffeine can improve endurance. Recently, it has also been shown to delay the onset of fatigue in exercise. The most probable mechanism for the delay of fatigue is through the obstruction of adenosine receptors in the central nervous system. Adenosine is a neurotransmitter that decreases arousal and increases sleepiness. By preventing adenosine from acting, caffeine removes a factor that promotes rest and delays fatigue.
The role of chemotherapy in DIPG remains unclear. Studies have shown little improvement in survival, although efforts (see below) through the Children's Oncology Group (COG), Paediatric Brain Tumour Consortium (PBTC), and others are underway to explore further the use of chemotherapy and other drugs. Drugs that increase the effect of radiotherapy (radiosensitizers) have shown no added benefit, but promising new agents are under investigation. Immunotherapy with beta-interferon and other drugs has also had little effect in trials. Intensive or high-dose chemotherapy with autologous bone marrow transplantation or peripheral blood stem cell rescue has not demonstrated any effectiveness in brain stem gliomas. Future clinical trials may involve medicines designed to interfere with cellular pathways (signal transfer inhibitors), or other approaches that alter the tumor or its environment.
Though no topical treatment has been proven to be effective in the treatment of Central Serous Retinopathy. Some doctors have attempted to use nonsteroidal topical medications to reduce the subretinal fluid associated with CSR. The nonsteroidal topical medications that are sometimes used to treat CSR are, Ketorolac, Diclofenac, or Bromfenac.
Spironolactone is a mineralocorticoid receptor antagonist that has been proven to help reduce the fluid associated with Central Serous Retinopathy. In a study noted by Acta Ophthalmologica also noted that the Spironolactone improved the visual acuity over the course of 8 weeks.
Epleronone is a mineralocorticoid receptor antagonist that has been proven to reduce the subretinal fluid that is present in Central Serous Retinopathy. This is a similar treatment to Spironolactone. In a study noted in International Journal of Ophthalmology, results showed Epleronone decreased the SRF both horizontally and vertically over time. Though after stopping the medication the fluid also appeared to return and patients needed further treatment.
Low dosage ibuprofen has been shown to quicken recovery in some cases, whilst avoiding naturally occurring blood thinners such as garlic, turmeric, cinnamon, which can enhance leakage from capillaries behind the retina.
There is much research that needs to be conducted on CCAS. A necessity for future research is to conduct more longitudinal studies in order to determine the long-term effects of CCAS. One way this can be done is by studying cerebellar hemorrhage that occurs during infancy. This would allow CCAS to be studied over a long period to see how CCAS affects development. It may be of interest to researchers to conduct more research on children with CCAS, as the survival rate of children with tumors in the cerebellum is increasing. Hopefully future research will bring new insights on CCAS and develop better treatments.
Education of patients, families, and caregivers is an important component of the appropriate treatment of PBA. Crying associated with PBA may be incorrectly interpreted as depression; laughter may be embarrassing. It is therefore critical for families and caregivers to recognize the pathological nature of PBA and the reassurance that this is an involuntary syndrome that is manageable.
Traditionally, antidepressants such as sertraline, fluoxetine,citalopram, nortriptyline and amitriptyline have been prescribed with some efficacy.
To date, there is no successful method of treatment that "cures" musical hallucinations. There have been successful therapies in single cases that have ameliorated the hallucinations. Some of these successes include drugs such as neuroleptics, antidepressants, and certain anticonvulsive drugs. A musical hallucination was alleviated, for example, by antidepressant medications given to patients with depression. Sanchez reported that some authors have suggested that the use of hearing aids may improve musical hallucination symptoms. They believed that the external environment influences the auditory hallucinations, showing worsening of symptoms in quieter environments than in noisier ones. Oliver Sacks' patient, Mrs. O'C, reported being in an "ocean of sound" despite being in a quiet room due to a small thrombosis or infarction in her right temporal lobe. After treatment, Mrs. O'C was relinquished of her musical experience but said that, "I do miss the old songs. Now, with lots of them, I can't even recall them. It was like being given back a forgotten bit of my childhood again." Sacks also reported another elderly woman, Mrs. O'M, who had a mild case of deafness and reported hearing musical pieces. When she was treated with anticonvulsive medications, her musical hallucinations ceased but when asked if she missed them, she said "Not on your life."
Treatment consists of Anti-VEGF drugs like Lucentis or intravitreal steroid implant (Ozurdex) and Pan-Retinal Laser Photocoagulation usually. Underlying conditions also require treatment. Non-Ischemic CRVO has better visual prognosis than Ischemic CRVO.
A systematic review studied the effectiveness of the anti-VEGF drugs ranibizumab and pagatanib sodium for patients suffering from non-ischemic CRVO. Though there was a limited sample size, participants in both treatment groups showed improved visual acuity over 6 month periods, with no safety concerns.