The Predictive Diagnostic and Prognostic Cut-off Values for Interleukin 8 in Patients with Meningitis in Egypt

Objectives: This work was done to detect the best cut-off values for IL-8 to diagnose CNS infections (meningitis and meningio-encephalitis), to differentiate septic from aseptic types, and to predict mortality.
Methods: A case- control series design was chosen, where 42 patients who were diagnosed clinically as having meningitis and 42 control subjects were subjected for lumbar puncture and their cerebrospinal fluids were examined physically, chemically, cytologically, and bacteriologically; besides the level of interleukin 8 (IL-8) was determined and compared for both groups.
Results: The mean value of IL-8 was 75.8±89.1 in cases group compared to 26.2±18.0 in the control group which was highly statistically significant; its best significant cut off value for detection of CNS infection (meningitis or meningio-encephalitis) is 44ng/ml, while the best significant cut off value to diagnose septic meningitis was 50 with sensitivity of 52% and specificity of 82.35%. The mortality in our cases was 16.6%, and IL-8 best significant cut off value to detect this mortality was140 with sensitivity of 100% and specificity of 89.47% with +ve likelihood ratio 9.5.
Conclusions: IL-8 in CSF is a valid good significant marker to diagnose the infection, differentiate septic from aseptic types besides the known parameters, and more over it significantly predicts mortality in cases with meningitis and meningio-encephalitis.