Clinical Features and Diagnosis of Multiple Sclerosis

Disease Subtypes and Patterns

The American Academy of Neurology suggests that Relapsing-Remitting MS (RRMS) affects approximately 85% of patients at onset, characterized by acute inflammatory episodes followed by periods of remission 1, 2, 3
The National Multiple Sclerosis Society indicates that RRMS is characterized by nerve conduction affected during acute phases but tends to improve during remission, with cumulative myelin damage and progressive neuronal loss over time 2, 3
The European Committee for Treatment and Research in Multiple Sclerosis states that Primary Progressive MS (PPMS) affects approximately 15% of patients, presenting with steadily increasing neurological disability from onset without distinct relapses 2, 3, 1

The American Academy of Neurology recommends that common neurological symptoms include optic neuritis, sensory disturbances, motor symptoms, diplopia, myelopathy, and balance and gait dysfunction 4, 5, 6
The National Institute of Neurological Disorders and Stroke suggests that symptoms develop over hours to days, typically stabilize, and often resolve spontaneously, with true relapses lasting at least 24 hours with new inflammatory demyelinating activity 4, 5, 1

The American Academy of Neurology indicates that atypical features requiring additional investigation include subacute onset over weeks, progressive evolution without stabilization, dementia, epilepsy, or aphasia as presenting features, and bilateral sudden hearing loss 4, 5, 1, 6
The National Multiple Sclerosis Society states that PML presents distinctly with aphasia, behavioral/neuropsychological changes, retrochiasmal visual deficits, hemiparesis, seizures, and a progressive course over weeks without stabilization 4, 5

The European Committee for Treatment and Research in Multiple Sclerosis recommends that classic MS lesion features include focal, periventricular location, lesions in corpus callosum and spinal cord, sharp edges, ovoid/flame-shaped, and orientation perpendicular to ventricles 4, 5, 1, 7
The American Academy of Neurology suggests that three or more periventricular lesions are required to demonstrate dissemination in space, and additional diagnostic locations include juxtacortical, infratentorial, and spinal cord regions 7, 1

The National Institute of Neurological Disorders and Stroke indicates that the typical diagnostic age range is between 10-59 years, and pediatric cases require special diagnostic care 6
The American Academy of Neurology recommends that older patients or those with vascular risk factors apply more stringent criteria, with a higher number of periventricular lesions required 6

The European Committee for Treatment and Research in Multiple Sclerosis states that core diagnostic requirements include evidence of CNS lesions disseminated in both time and space, at least one clinical event consistent with acute demyelination, and exclusion of alternative diagnoses 6, 1
The National Multiple Sclerosis Society suggests that supportive paraclinical findings include oligoclonal bands specific to CSF, visual evoked potentials showing delayed conduction, and critical differential diagnoses to exclude such as NMOSD, cerebrovascular disease, infectious diseases, paraneoplastic disorders, and monophasic demyelinating diseases 1, 7, 6