The administration of immunotherapy, in association with chemotherapy or tumor removal, .

A complete recovery following immunotherapy and tumor removal. Untreated cases died within few months of onset. Some patients have a poor outcome despite sustained immunosuppression, but that is often related to tumor progression or associated with the presence of Abs directed against intracellular Ags such as GAD Abs or amphyphysin Abs, which can reflect the involvement of an additional cytotoxic T-cell mechanism in the progression of the disease.

In a recent analysis (Susac et al., 2003), MRI images from 27 patients fulfilling the diagnostic criteria of Susac's syndrome were reviewed. Multifocal supratentorial lesions were present in all patients. Most lesions were small (3 to 7 mm), though some were larger than 7 mm. All 27 patients had corpus callosum lesions. These all had a punched-out appearance on follow up MRI. Though most commonly involving white matter, many patients also had lesions in deep grey matter structures, as well as leptomeningeal enhancement. Multiple sclerosis (MS) and acute disseminated encephalomyelitis (ADEM) can mimic the MRI changes seen in patients with Susac's syndrome. However, the callosal lesions in Susac's syndrome are centrally located. In comparison, patients with MS and ADEM typically have lesions involving the undersurface of the corpus callosum. Deep gray matter involvement commonly occurs in ADEM but is very rare in MS. Leptomeningeal involvement is not typical of either MS or ADEM. What this means is that if 10 lesions are found in the brain of an MS patient, a lesion may be found in the corpus callosum. If you have 10 lesions in a Susac patient, more than half will be in the corpus callosum.

A concern about this illness is that it mimics multiple sclerosis when looking at the vision loss and brain lesions. If close attention is not paid to the retina of a patient with vision loss and brain lesions, their symptoms may be mistaken for MS instead of Susac's syndrome. This may account for the low prevalence of the illness. There is also a pathological similarity between the endotheliopathy in Susac's syndrome with that seen in juvenile dermatomyositis.

SPS is diagnosed by evaluating clinical findings and excluding other conditions. There is no specific laboratory test that confirms its presence. Underdiagnosis and misdiagnosis are common.

The presence of antibodies against GAD is the best indication of the condition that can be detected by blood and cerebrospinal fluid (CSF) testing. Anti-GAD65 is found in about 80 percent of SPS patients. Anti-thyroid, anti-intrinsic factor, anti-nuclear, anti-RNP, and anti-gliadin are also often present in blood tests. Electromyography (EMG) demonstrates involuntary motor unit firing in SPS patients. EMG can confirm the diagnosis by noting spasms in distant muscles as a result of subnoxious stimulation of cutaneous or mixed nerves. Responsiveness to diazepam helps confirm that the patient is suffering from SPS, as this decreases stiffness and motor unit potential firing.

The same general criteria are used to diagnose paraneoplastic SPS as the normal form of the condition. Once SPS is diagnosed, poor response to conventional therapies and the presence of cancer indicate that it may be paraneoplastic. CT scans are indicated for SPS patients who respond poorly to therapy to determine if this is the case.

A variety of conditions have similar symptoms to SPS, including myelopathies, dystonias, spinocerebellar degenerations, primary lateral sclerosis, neuromyotonia, and some psychogenic disorders. Tetanus, neuroleptic malignant syndrome, malignant hyperpyrexia, chronic spinal interneuronitis, serotonin syndrome, Multiple sclerosis, Parkinson's disease, and Isaacs syndrome should also be excluded.

Patients' fears and phobias often incorrectly lead doctors to think their symptoms are psychogenic, and they are sometimes suspected of malingering. It takes an average of six years after the onset of symptoms before the disease is diagnosed.

Early and aggressive treatment is important to prevent irreversible neurological damage, hearing loss, or vision loss. Medications used include immunosuppressive agents and corticosteroids such a prednisone, or intravenous immunoglobulins (IVIG). Other drugs that have been used are mycophenolate mofetil (Cellcept), azathioprine (Imuran), cyclophosphamide, rituximab, and anti-TNF therapies.

Hearing aids or cochlear implants may be necessary in the event of hearing loss.

AQP4-Ab-negative NMO presents problems for diagnosis. The behavior of the oligoclonal bands respect MS can help to establish a more accurate diagnosis. Oligoclonal bands in NMO are rare and they tend to disappear after the attacks, while in MS they are nearly always present and persistent.

It is important to notice for differential diagnosis that, though uncommon, it is possible to have longitudinal lesions in MS

Other problem for diagnosis is that AQP4ab in MOGab levels can be too low to be detected. Some additional biomarkers have been proposed.

The Mayo Clinic proposed a revised set of criteria for diagnosis of Devic's disease in 2006. Those new guidelines require two absolute criteria plus at least two of three supportive criteria. In 2015 a new review was published by an international panel refining the previous clinical case definition but leaving the main criteria unmodified:

Absolute criteria:

1. Optic neuritis

2. Acute myelitis

Supportive criteria:

1. Brain MRI not meeting criteria for MS at disease onset

2. Spinal cord MRI with continuous T2-weighted signal abnormality extending over three or more vertebral segments, indicating a relatively large lesion in the spinal cord

3. NMO-IgG seropositive status (The NMO-IgG test checks the existence of antibodies against the aquaporin 4 antigen.)

The CDC MMWR report advised, "To prevent infections in general, persons should stay home if they are ill, wash their hands often with soap and water, avoid close contact (such as touching and shaking hands) with those who are ill, and clean and disinfect frequently touched surfaces."

Unlike polio, acute flaccid myelitis can not currently be prevented with a vaccine.

The diagnosis may be made on the clinical features alone, along with tests to rule out other possible causes. An EEG will usually show the electrical features of epilepsy and slowing of brain activity in the affected hemisphere, and MRI brain scans will show gradual shrinkage of the affected hemisphere with signs of inflammation or scarring.

Brain biopsy can provide very strong confirmation of the diagnosis, but this is not always necessary.

There are no characteristic laboratory abnormalities to diagnose CFS; testing is used to rule out other conditions which could be responsible for the symptoms. When symptoms are attributable to certain other conditions, the diagnosis of CFS is excluded. As such, a diagnosis of CFS/ME is generally one of exclusion (of alternative diagnoses).

Diagnosis of tumefactive MS is commonly carried out using magnetic resonance imaging (MRI) and proton MR spectroscopy (H-MRS). Diagnosis is difficult as tumefactive MS may mimic the clinical and MRI characteristics of a glioma or a cerebral abscess. However, as compared to tumors and abscesses, tumefactive lesions have an open-ring enhancement as opposed to a complete ring enhancement. Even with this information, multiple imaging technologies have to be used together with biochemical tests for accurate diagnosis of tumefactive MS.

Tumefactive demyelination is distinguished from tumor by the presence of multiple lesions, absence of cortical involvement, and decrease in lesion size or detection of new lesions on serial imaging

In the classic presentation of the disease death usually occurs within 3 years, however there are rarely both fast and slower progressions. Faster deterioration in cases of acute fulminant SSPE leads to death within 3 months of diagnosis.

If the diagnosis is made during stage 1 of the SSPE infection then it may be possible to treat the disease with oral isoprinosine (Inosiplex) and intraventricular interferon alfa, but the response to these drugs varies from patient to patient. However, once SSPE progresses to stage 2 then it is universally fatal in all occurrences. The standard rate of decline spans anywhere between 1–3 years after the onset of the infection. The progression of each stage is unique to the sufferer and cannot be predicted although the pattern or symptoms/signs can be.

Although the prognosis is bleak for SSPE past stage 1, there is a 5% spontaneous remission rate—this may be either a full remission that may last many years or an improvement in condition giving a longer progression period or at least a longer period with the less severe symptoms.

Notable definitions include:

- Centers for Disease Control and Prevention (CDC) definition (1994), the most widely used clinical and research description of CFS, is also called the Fukuda definition and is a revision of the "Holmes" or "CDC 1988" scoring system. The 1994 criteria require the presence of four or more symptoms beyond fatigue, while the 1988 criteria require six to eight.

- The ME/CFS 2003 Canadian Clinical working definition states: "A patient with ME/CFS will meet the criteria for fatigue, post-exertional malaise and/or fatigue, sleep dysfunction, and pain; have two or more neurological/cognitive manifestations and one or more symptoms from two of the categories of autonomic, neuroendocrine, and immune manifestations; and the illness persists for at least 6 months".

Clinical practice guidelines are generally based on case descriptions, with the aim of improving diagnosis, management and treatment. An example is the CFS/ME guideline for the National Health Services in England and Wales, produced in 2007 by the National Institute for Health and Clinical Excellence (NICE).

Diagnostic testing in a possible paraneoplastic syndrome depends on the symptoms and the suspected underlying cancer.

Diagnosis may be difficult in patients in whom paraneoplastic antibodies cannot be detected. In the absence of these antibodies, other tests that may be helpful include MRI, PET, lumbar puncture and electrophysiology.

Myelitis has an extensive differential diagnosis. The type of onset (acute versus subacute/chronic) along with associated symptoms such as the presence of pain, constitutional symptoms that encompass fever, malaise, weight loss or a cutaneous rash may help identify the cause of myelitis. In order to establish a diagnosis of myelitis, one has to localize the spinal cord level, and exclude cerebral and neuromuscular diseases. Also a detailed medical history, a careful neurologic examination, and imaging studies using magnetic resonance imaging (MRI) are needed. In respect to the cause of the process, further work-up would help identify the cause and guide treatment. Full spine MRI is warranted, especially with acute onset myelitis, to evaluate for structural lesions that may require surgical intervention, or disseminated disease. Adding gadolinium further increases diagnostic sensitivity. A brain MRI may be needed to identify the extent of central nervous system (CNS) involvement. Lumbar puncture is important for the diagnosis of acute myelitis when a tumoral process, inflammatory or infectious cause are suspected, or the MRI is normal or non-specific. Complementary blood tests are also of value in establishing a firm diagnosis. Rarely, a biopsy of a mass lesion may become necessary when the cause is uncertain. However, in 15–30% of people with subacute or chronic myelitis, a clear cause is never uncovered.

MRI diagnosis is based on lesions that are disseminated in time and space, meaning that there are multiple episodes and consisting of more than one area. There are two kinds of MRI used in the diagnosis of tumefactive MS, T1-weighted imaging and T2-weighted imaging. Using T1-weighted imaging, the lesions are displayed with low signal intensity, meaning that the lesions appear darker than the rest of the brain. Using T2-weighted imaging, the lesions appear with high signal intensity, meaning that the lesions appear white and brighter than the rest of the brain. When T1-weighted imaging is contrast-enhanced through the addition of gadolinium, the open ring enhancement can be viewed as a white ring around the lesion. A more specific MRI, Fluid attenuation inversion recovery (FLAIR) MRI show the signal intensity of the brain. Subjects with tumefactive multiple sclerosis may see a reduction of diffusion of the white matter in the affected area of the brain.

The progression of SPS depends on whether it is a typical or abnormal form of the condition and the presence of comorbidities. Early recognition and neurological treatment can limit its progression. SPS is generally responsive to treatment, but the condition usually progresses and stabilizes periodically. Even with treatment, quality of life generally declines as stiffness precludes many activities. Some patients require mobility aids due to the risk of falls. About 65 percent of SPS patients are unable to function independently. About ten percent of SPS patients require intensive care at some point; sudden death occurs in about the same number of patients. These deaths are usually caused by metabolic acidosis or an autonomic crisis.

Currently the mechanism of spread and infection is unknown despite the tedious epidemiological, clinical, and neurological studies that have been conducted. Recent Studies show Horizontal Disease Transmission, or the transmission of a disease from one individual to another of the same generation. It appears that VE is an infectious disease; however, the incubation period would have to be very extensive (in excess of 5 years). Many infected individuals attribute the initial symptoms as a result of a plunge in frigid waters. So far, no causative agent has been found in blood, spinal fluid, or brain tissue.

Characteristic periodic activity (Rademecker complex) is seen on electroencephalogram (EEG) showing widespread cortical dysfunction; pathologically, the white matter of both the hemispheres and brainstem are affected, as well as the cerebral cortex, and eosinophilic inclusion bodies are present in the nuclei of neurons (gray matter) and oligodendrocytes (white matter).

The diagnosis of SSPE is based on signs and symptoms (Changes in personality, a gradual onset of mental deterioration and myoclonia) and on test results, such as typical changes observed in EEGs, an elevated anti-measles antibody (IgG) in the serum and cerebrospinal fluid, and typical histologic findings in brain biopsy tissue.

Six of ten children in Denver were sent home for outpatient treatment; some with mild symptoms have recovered from temporary limb weakness, while the fate of those more severely affected remains unclear. Intensive physical therapy and occupational therapy may be beneficial for recovery.

Also inside standard MS different clinical courses can be separated.

Currently there is no single diagnosis test for MS that is 100% sensitive and specific. To have such a thing would require a standardised definition of the disease, which currently does not exist. The most commonly used definition, based in the McDonald criteria, focuses in the presence and distribution of the lesions, not in the underlying condition that produces them. Therefore, even twins with the same underlying condition can be classified different

In the US, neuroborreliosis is typically treated with intravenous antibiotics which cross the blood–brain barrier, such as penicillins, ceftriaxone, or cefotaxime. One relatively small randomized controlled trial suggested ceftriaxone was more effective than penicillin in the treatment of neuroborreliosis. Small observational studies suggest ceftriaxone is also effective in children. The recommended duration of treatment is 14 to 28 days.

Several studies from Europe have suggested oral doxycycline is equally as effective as intravenous ceftriaxone in treating neuroborreliosis. Doxycycline has not been widely studied as a treatment in the US, but antibiotic sensitivities of prevailing European and US isolates of "Borrelia burgdorferi" tend to be identical. However, doxycycline is generally not prescribed to children due to the risk of bone and tooth damage.

Discreditied or doubtful treatments for neuroborreliosis include:

- Malariotherapy

- Hyperbaric oxygen therapy

- Colloidal silver

- Injections of hydrogen peroxide and bismacine

During the acute stage, treatment is aimed at reducing the inflammation. As in other inflammatory diseases, steroids may be used first of all, either as a short course of high-dose treatment, or in a lower dose for long-term treatment. Intravenous immunoglobulin is also effective both in the short term and in the long term, particularly in adults where it has been proposed as first-line treatment. Other similar treatments include plasmapheresis and tacrolimus, though there is less evidence for these. None of these treatments can prevent permanent disability from developing.

During the residual stage of the illness when there is no longer active inflammation, treatment is aimed at improving the remaining symptoms. Standard anti-epileptic drugs are usually ineffective in controlling seizures, and it may be necessary to surgically remove or disconnect the affected cerebral hemisphere, in an operation called hemispherectomy. This usually results in further weakness, hemianopsia and cognitive problems, but the other side of the brain may be able to take over some of the function, particularly in young children. The operation may not be advisable if the left hemisphere is affected, since this hemisphere contains most of the parts of the brain that control language. However, hemispherectomy is often very effective in reducing seizures.

Treatment options include:

1. Therapies to eliminate the underlying cancer, such as chemotherapy, radiation and surgery.

2. Therapies to reduce or slow neurological degeneration. In this scenario, rapid diagnosis and treatment are critical for the patient to have the best chance of recovery. Since these disorders are relatively rare, few doctors have seen or treated paraneoplastic neurological disorders (PNDs). Therefore, PND patients should consult with a specialist with experience in diagnosing and treating paraneoplastic neurological disorders.

A specific prognosis for those afflicted with paraneoplastic syndromes links to each unique case presented. Thus, prognosis for paraneoplastic syndromes may vary greatly. For example, paraneoplastic pemphigus often included infection as a major cause of death. Paraneoplastic pemphigus is one of the three major subtypes that affects IgG autoantibodies that are characteristically raised against desmoglein 1 and desmoglein 3 (which are cell-cell adhesion molecules found in desmosomes). Underlying cancer or irreversible system impairment, seen in acute heart failure or kidney failure, may result in death as well.