The National Institute of Neurological Disorders and Stroke (NINDS) states that meningitis and encephalitis are two neurological conditions where the membranes around the brain and the spinal cord, which make up the central nervous system (CNS), are inflamed. The cause of these disorders is a viral or bacterial infection. The severity of both inflammatory brain diseases range from mild to fatal; some cases resulting in death. Their difference in symptoms include how they affect the brain after infection and the symptoms.
When a patient has meningitis, the inflammation results in a change in the cerebrospinal fluid (CSF), which affects the protection of the brain. The National Institutes of Health (NIH) notes that there are multiple forms of meningitis, which include tuberculous meningitis, aseptic meningitis, syphilitic aseptic meningitis, cryptococcal meningitis, staphylococcal meningitis, gram negative meningitis, pneumococcal meningitis, H. influenza meningitis and meningococcal meningitis. Meningitis can also result from cancer, also known as carcinomatous meningitis. Other causes include tumors, fungi, drug allergies and chemical irritation.