Laboratory Testing: Neurologic Manifestations with Rheumatic Diseases—Associated Findings and Recommended Laboratory Evaluation

In this chapter, laboratory tests relevant to major disorders in rheumatology that can affect the nervous system are discussed. While laboratory tests can be helpful in evaluating patients with suspected or established rheumatic disease, they are often not diagnostic due to imperfect sensitivity and specificity. Therefore, it is particularly important to recognize that the pretest probability of disease is the driving factor in determining the utility of any laboratory value. Laboratory testing may make a particular diagnosis more or less likely, but ultimately, consideration of the clinical context is essential for disease diagnosis. In many cases, laboratory testing is more helpful to rule out disease than to rule in disease.