Cerebrospinal Fluid Collection and Repository Storage

Background: \- Cerebrospinal fluid (CSF) is the liquid around the brain and spinal cord. Many diseases can only be diagnosed by examining the CSF. A lumbar puncture is used to collect and test CSF. Once someone is already having a lumbar puncture, a small extra amount of CSF can be collected at the same time. This fluid can be used to study brain, nerve, and related health issues. Researchers want to collect CSF and blood samples from people who are scheduled to have a lumbar puncture. Objectives: \- To collect cerebrospinal fluid and blood samples from individuals who are having a lumbar puncture. Eligibility: \- Individuals between 2 and 100 years of age who are scheduled to have a lumbar puncture for clinical or research purposes. Design: * Participants will have a lumbar puncture for clinical or research purposes. * During the procedure, an additional sample of CSF will be collected. They will also provide a blood sample, if one is not taken at the time of the procedure. * Treatment will not be provided as part of this study.