Difficulties encountered in recruiting patients

In the primary progressive multiple sclerosis, the detection of oligoclonal bands in cerebrospinal fluid is critical for the diagnosis. However, lumbar puncture for cerebrospinal fluid collection is considered relatively invasive. Our hypothesis is that oligoclonal bands detection in tears is possible and useful for the diagnosis of multiple sclerosis.

The objective of the present study is to assess concordance between oligoclonal bands detection in tears and in cerebrospinal fluid. We will include patients with primary progressive multiple sclerosis and we will compare results of oligoclonal bands detection by isoelectric focusing in cerebrospinal fluid and tears. Tears will be collected using a Schirmer strip. This would circumvent the practice of invasive lumbar punctures currently used in multiple sclerosis diagnosis.

Inclusion Criteria:

• 18 years old or more
• Progressive neurological deficit after 12 months
• At least 9 T2 brain lesions of minimum 3 mm evidenced by MRI and/or four or more T2 lesions of minimum 3 mm with positive Visual Evoked Potential and/or positive spinal cord MRI (at least two focal T2 lesions)

Exclusion Criteria:

• Asiatic persons
• recurrent forms of the disease
• Persons wearing contact lenses
• Ocular Infection
• Corticoid treatment at least 30 days before sampling
• immunosuppressive or immunomodulatory treatment 3 months before sampling