Meningitis bacteria (Neisseria meningitidis) colonies (white) being cultured on an agar growth medium (brown) in a petri dish. Meningitis is the inflammation of the brain membranes. It can be caused by several bacteria. Typical meningitis symptoms are a severe headache and stiff neck, followed by delirium and coma. Without antibiotic treatment it is often fatal. Grown on a combined chocolate and IsoVitaleX agar. Chocolate agar is a blood-enriched agar specially formulated for culturing Neisseria bacteria. IsoVitaleX is a commercial mix of other nutrients needed to grow these bacteria.