• interleukin-6;
  • cerebrospinal fluid;
  • Alzheimer's disease

Objectives– In view of contradictory findings in previous studies, to examine the diagnostic value of interleukin-6 measurements in cerebrospinal fluid (CSF) of Alzheimer's disease patients. Material and methods– Interleukin-6-immunoreactivity (IL-6-IR) was measured in 169 intra vitam lumbar and 21 post mortem ventricular CSF samples of patients with probable and neuropathologically confirmed Alzheimer's disease (AD), non-AD dementias (NAD), neurological disorders without cognitive impairment (OND) and controls (CON) using a specific sandwich enzyme immunoassay. ResultsIntra vitam lumbar samples had significantly elevated (P<0.03) IL-6-IR not only in the AD, but also in the NAD and OND group compared with controls. AD patients with late onset (>65 years) had slightly (P>0.05) higher values than patients with early onset (<65 years). In post mortem ventricular fluid, differences among groups did not reach significance (P>0.05). Conclusion– We conclude that elevations of CSF IL-6-IR can not serve as a diagnostic marker of the disease, but, hypothetically, could reflect presence or activity of IL-6 mediated immunological phenomena in single AD patients.