Diagnostic problems in "clinically definite" multiple sclerosis patients with normal CSF and multiple MRI...

Area of Science:

• Neurology
• Neuroimmunology

Background:

• Multiple sclerosis (MS) diagnosis traditionally relies on clinical presentation, MRI findings, and cerebrospinal fluid (CSF) analysis.
• Disseminated white matter lesions on MRI and clinical symptoms suggestive of MS are key diagnostic indicators.
• Normal CSF findings in patients with suspected MS present a diagnostic challenge.

Purpose of the Study:

• To investigate the diagnostic accuracy of current criteria in patients presenting with MS-like symptoms but normal CSF.
• To identify alternative diagnoses in patients with clinically definite MS, MRI white matter abnormalities, and normal CSF.
• To assess the specificity of MS diagnostic criteria when CSF analysis is unremarkable.

Main Methods:

• Retrospective analysis of 18 patients diagnosed with clinically definite MS, MRI white matter abnormalities, and normal CSF.
• Inclusion criteria: disease duration ≥ 1 year, age < 45 years at onset.
• Patients underwent extensive laboratory testing to screen for mimic diseases.

Main Results:

• Six out of 18 patients (33.3%) received an alternative final diagnosis after further testing.
• Diagnoses included Lyme disease, vasculitis, mitochondrial encephalomyopathy, ischemic lesions, and olivopontocerebellar atrophy.
• Twelve patients (66.7%) were ultimately diagnosed with "MS with normal CSF".

Conclusions:

• Classical clinical and MRI criteria for MS may lack specificity in cases with normal CSF.
• Prolonged clinical history and serial MRI examinations are crucial for confirming MS diagnosis in ambiguous cases.
• The differential diagnosis for MS should be broadened in patients with unremarkable CSF findings.