Review symptoms and medical history (neurologic episodes, onset, progression)
Perform neurologic exam (strength, sensation, reflexes, coordination, gait, vision)
Obtain MRI of brain and spinal cord with and without contrast
Look for dissemination in space (lesions in multiple characteristic CNS regions)
Look for dissemination in time (new or enhancing lesions on follow-up MRI, or simultaneous enhancing and non-enhancing lesions)
Use lumbar puncture for cerebrospinal fluid analysis when needed
Test CSF for oligoclonal bands and other supportive markers
Perform evoked potentials (visual evoked potentials, somatosensory evoked potentials) when indicated
Rule out alternative diagnoses with targeted testing
Order blood tests to exclude mimics (e.g., autoimmune, infectious, metabolic, vitamin deficiencies, vascular causes)
Consider testing for neuromyelitis optica spectrum disorder (AQP4-IgG) when clinically appropriate
Consider testing for MOG-associated disease (MOG-IgG) when clinically appropriate
Assess for other inflammatory/demyelinating conditions (based on clinical and MRI patterns)
Use diagnostic criteria (e.g., McDonald criteria) to confirm MS based on MRI/CSF/clinical data
Confirm diagnosis with a neurologist specializing in demyelinating disease
Document baseline disability and neurologic function for ongoing monitoring