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What is Malignant multiple sclerosis and explain in detail?
Malignant multiple sclerosis is used to describe MS patients who reach significant level of disability in a short period of time. Malignant MS cases are not common, less than 5% of patients with MS experience this type of progression.The National MS Society Advisory Committee on Clinical Trials of New Agents consensus defined it as: disease with a rapid progressive course, leading to significant disability in multiple neurologic systems or death in a relatively short time after disease onset. Reaching Expanded Disability Status Scale of 6.0 or higher, which is equivalent of needing unilateral support to ambulate  (or worse) is generally considered this significant disability level.Patients with severe forms of more common relapsing remitting or progressive MS subtypes, as well as rare Marburg variant and Balo concentric sclerosis, could be considered to have malignant MS. Patients should be carefully worked up to rule out Neuromyelitis optica (Devics disease) due to the distinctive pathophysiology and management strategies of this disease.

Signs and symptoms
Some common physical symptoms may include: "weakness in extremities, difficulties with coordination and balance, spasticity, paresthesia, speech impediments, tremors, dizziness, hearing loss, vision impairments, bowel and bladder difficulties"

Diagnosis
Earlier signs include an increase in mobility over a short period of time. Malignant MS happens in patients that already have or have been diagnosed with MS