What does cerebrospinal fluid (CSF) testing help diagnose?

Cerebrospinal fluid (CSF) testing is primarily utilized to diagnose conditions affecting the central nervous system (CNS), with a focus on infections such as meningitis and encephalitis. When CSF is collected through a procedure called a lumbar puncture, it can be analyzed for various indicators, including white blood cell counts, protein levels, and glucose levels. Elevated white blood cell counts may suggest infection, while changes in protein and glucose levels can help differentiate between types of meningitis, such as bacterial, viral, or fungal.

In this context, CSF testing is crucial because meningitis can lead to severe complications if not identified and treated promptly. Therefore, the primary role of CSF analysis is to help clinicians make a timely diagnosis of CNS infections. Other options, such as pneumonia, cardiovascular diseases, or metabolic conditions, do not directly involve CSF analysis, making the second choice the most appropriate.