Avoiding the Headache: Laboratory Considerations for Implementation, Utilization, and Interpretation of Multiplex Molecular Panels for the Diagnosis of Meningitis and Encephalitis, Part I

Meningitis and encephalitis are infections of the central nervous system (CNS) that can range in severity from mild and self-limiting to severe and life threatening. These infections can be caused by a number of bacterial, viral, and fungal pathogens. Appropriate management of these infections is dependent upon an accurate and rapid identification of the infecting organism. Despite diagnostic advances with improved detection and turnaround time, currently, the etiological pathogen in central nervous system infections is identified in only 30 to 50% of symptomatic patients. The development of targeted molecular tests has begun to address these shortcomings, and the recent FDA clearance of the first broadly multiplexed test for meningitis/encephalitis has great potential to improve laboratory diagnosis of these infections. However, a thorough understanding of the performance and limitations of these tests is critical to ensure maximal patient benefit and to mitigate the reporting of potentiality erroneous or misleading results. Part I of this article provides a basic review of the infectious causes of meningitis/encephalitis, as well as the performance and shortcomings of current diagnostic approaches.