Five new markers (tumor necrosis factor TNF-alpha, interleukin IL-1 beta, IL-6, IL-8, lipopolysaccharide binding protein (LBP)) and 11 old classical markers were evaluated in 180 cerebrospinal fluid (CSF) and serum pairs to discriminate acute bacterial meningitis (BM) on admission from aseptic (viral) meningitis (AM), bacterial meningitis treated with antibiotics (TM) from AM, and AM from multiple sclerosis (MS). Statistical tests were computed which classified correctly > or =90% of the patients with BM, TM, AM at a sum minimum of false positive plus false negative results, and which reached additionally > or =90% sensitivity and specificity. To discriminate BM from AM, CSF IL-6 test > or =500 ng/l and CSF IL-1 beta test > or =8 ng/l besides CSF lactate test > or =3.5mM/l and CSF granulocyte test > or =150 M/l were revealed. CSF lactate test > or =3.2 mmol/l discriminated TM from AM. CSF leukocyte test > or =35 M/l discriminated AM from MS. Tests with the new markers were more laborious, expensive, and time consuming compared to CSF lactate test. Test candidates, detecting > or =80% of patients with > or =80% sensitivity and specificity, were evaluated with CSF TNF-alpha, IL-8 and LBP, serum IL-6, CSF leukocytes, lymphocytes and monocytes, Qglucose, CSF total protein, albumin, and Qalbumin. All tests should be reviewed in context of clinical findings to diagnose BM reliably.