WESTPORT, CT (Reuters Health) Jan 17 - Reduced levels of cystatin C in the cerebrospinal fluid (CSF) may be a useful marker for some inflammatory neurologic diseases, Japanese investigators report. Specifically, they observed low levels of cystatin C in the CSF of patients with Guillain-Barre syndrome, chronic inflammatory demyelinating polyneuropathy, and multiple sclerosis (MS).
Dr. Atsushi Nagai and associates of the Shimane Medical University in Izumo assayed cystatin C, cathepsin B and cathepsin H activity in CSF samples from 41 patients with inflammatory neurologic diseases, including patients with aseptic meningitis. The same assays were performed for samples from 35 healthy controls and 15 patients with neurodegenerative disease. The findings appear in the December issue of Neurology.
Cystatin C level was decreased and cathepsin B activity increased in the 8 patients with Guillain-Barre syndrome, the 5 with chronic inflammatory demyelinating polyneuropathy, and the 12 with MS.
Because CSF cystatin C levels were not decreased in patients with aseptic meningitis, the researchers postulate that lower cystatin C levels seen in the other inflammatory neurologic diseases may not be due to the overflow of the peripheral circulation into the intrathecal space. Instead, they speculate, "it may be caused by reduced production or increased degradation of cystatin C in inflammatory central nervous system lesions."
Dr. Nagai's group notes that high cathepsin B levels were observed in patients with Guillain-Barre and MS who were seriously ill. They therefore suggest that cystatin C may participate in the regulation of cathepsin B activity in CSF during periods of acute inflammation.
2000 Reuters Ltd.