What is the primary method for diagnosing meningitis?

The primary method for diagnosing meningitis is through a lumbar puncture, commonly known as a spinal tap. This procedure involves inserting a needle into the lower back to collect cerebrospinal fluid (CSF) surrounding the brain and spinal cord. Analyzing this fluid is critical for identifying the presence of infections, as well as determining the type of microorganisms causing the meningitis, whether they are bacterial, viral, fungal, or tuberculous.

CSF analysis can reveal elevated white blood cell counts, which indicate an inflammatory response, along with changes in protein and glucose levels that help differentiate between types of meningitis. This direct analysis of the cerebrospinal fluid provides definitive evidence of the condition, making lumbar puncture the gold standard for diagnosis.

Other methods such as CT scans, X-rays, or blood tests can provide valuable information about the overall health and may help rule out other conditions, but they do not provide the specific information needed to confirm meningitis or ascertain its cause.