New diagnostic method for Multiple Sclerosis
The diagnosis of Multiple Sclerosis (MS) is complex and must be carried out taking account of the clinical evidence of spatial dissemination (symptoms and signs that indicate the presence of two independent lesions in the central nervous system) and temporal dispersion (two or more episodes of neurological dysfunction). There are also a series of paraclinical tests, such as MRI, evoked potentials and oligoclonal bands (OB) that contribute to an accurate diagnosis of MS in most cases. The process of diagnosis is completed with tests conducted to rule out other diseases that may mimic MS such as Devic’s Disease, Sarcoidosis, Isolated Vasculitis of the central nervous system and Lyme’s Disease. Until now, the most common paraclinical test to confirm the diagnosis of MS is the presence of oligoclonal bands (OB) in cerebrospinal fluid. And the most sensitive detection method is isoelectric focusing in polyacrylamide gel which allows the detection of OB in up to 95% of MS cases. The main drawback of this technique is the need to perform a lumbar puncture on the patient, a very invasive and costly procedure.
The newly-developed analytic diagnosis method provides a paraclinical test to diagnose individuals with MS through the detection of a unique protein using ELISA in serum samples. The test has a sensitivity to distinguish between patients with MS and healthy controls of 71% and a specificity of 76.3%, obtaining an area under the curve (AUC) of 0.79. The results obtained in the initial cohort have been replicated in another independent one in which over 400 samples have been analysed. Also, the test contributes to the differential diagnosis of MS to other inflammatory neurological diseases with a positive predictive value of 88.4%.
It provides a less invasive, bloodless and therefore, more innocuous method for diagnosing MS.
This technique costs less than the OB-based method used until the present.
It could be used as a preliminary screening method, so that it would be necessary to perform oligoclonal band tests only on patients who give ELISA values that are not clear-cut.
It is valid to distinguish between patients with MS and healthy controls and also distinguish those patients with other inflammatory neurological diseases that might lead to confusion with their diagnosis.
- Central nervous system