Cerebrospinal Fluid Interleukin-1 β/InterLeukin-1 Receptor Antagonist Balance and Tumor Necrosis Factor-α Concentrations in Tuberculous, Viral and Acute Bacterial Meningitis

Abstract

The levels of interleukin-1β, IL-1 receptor antagonist and tumor necrosis factor-α (TNF-α) were analyzed in 19 cases of tuberculous, 14 cases of viral, and 22 cases of acute bacterial meningitis, and in 18 control subjects. 20 patients (91%) with acute bacterial and 8(42%) with tuberculous meningitis had detectable amounts of TNF-α in the initial cerebrospinal fluid (CSF) sample (mean 1044 ± 131 pg/ml, range 95–1950, and mean 61 ± 23 pg/ml, range 25–300, respectively), whereas TNF-α was not detectable in any of the patients with viral meningitis, or in any of the control subjects. IL-1β levels were 767 ± 110 pg/ml (185–2000) in acute bacterial, 345 ± 63 pg/ml (50–670) in tuberculous, 257 ± 70 pg/ml (20–700) in viral meningitis, and 37 ± 4 pg/ml (10–68) in control subjects. Il–1 receptor antagonist concentrations were significantly elevated in all meningitis groups, without significant differences between the groups. Il-1 receptor antagonist levels were 2487 ± 62 pg/ml (2250–2950) in acute bacterial, 2216 ± 82 pg/ml (1350–2550) in tuberculous and 1985 ± 92 pg/ml (650–2500) in viral meningitis, and 154 ± 26 pg/ml (20–245) in control CSF samples. A positive correlation was found between TNF and IL-1β levels (p < 0.01), and TNF levels and conscious state (p < 0.05). The ratio of concentrations of IL-1 receptor antagonist to IL-1β was 3.2 in acute bacterial meningitis, 6.9 in tuberculous meningitis and 8.3 in viral meningitis. This ratio was significantly different between the acute bacterial meningitis group and the other groups (p < 0.01), which indicates that the balance between cytokines and antagonists is of importance for the pathogenicity and diagnosis of central nervous system infections.