[The laboratory diagnosis of multiple sclerosis]

The importance of laboratory methods for multiple sclerosis (MS) diagnosis and differential diagnosis is often overestimated now. The role of several methods including MRI, evoked potentials, examination of the cerebrospinal fluid and some others methods are discussed in this review. Several conditions may in some patients mimick the appearance of MS and it is easy to understand why there is a tendency among many clinicians to embark on extensive- and expensive-laboratory investigations to establish the correct diagnosis at early stages of the disease. Disorders like cerebrovascular diseases, vasculitis, Lyme disease, neurosarcoidosis, acute disseminated encephalomyelitis, progressive multifocal leukoencephalopathy, HIV-associated encephalitis may cause very close changes of the results of these examinations. A detailed, exhaustive history and the neurological examination, along with a careful scrutiny of the actual MRI films by the neurologist experienced in the diagnosis of MS, will obviate the need for additional tests in the overwhelming majority of cases. So, the MS diagnosis and differential diagnosis is still based mainly of the data of clinical observation.