English 
Italian Determinazione delle immunoglobuline e delle catene leggere libere nel siero e nel liquido cefalorachidiano di un paziente con patologia autoinfiammatoria
AUTORI
1Laboratorio di Patologia Clinica e Genetica Medica, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milano
2Neurologia VIII, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milano
ABSTRACT
Serum and cerebrospinal fluid immunoglobulins and free light chains measurements in a patient with autoinflammatory disease
Serum and cerebrospinal fluid immunoglobulins and free light chains measurements in a patient with autoinflammatory disease. We report a case of a patient with chronic meningitis, headache, deafness, leukoencephalopathy, and osteomyelitis who showed a selective interleukin-6 (IL-6) overproduction. An inflammatory pattern was observed in serum; the cerebrospinal fluid (CSF) examination revealed positive oligoclonal IgG bands and IgG, IgA, IgM intrathecal synthesis. CSF free light chains (FLC) indices were very high. Steroids gave modest benefits. IL-6 was persistently increased in CSF and serum; after treatment with Tocilizumab, an anti IL6-receptor monoclonal antibody, the serum inflammatory pattern normalized and FLC decreased. Central neurological symptoms improved to a lesser degree than systemic ones, probably due to Tocilizumab blood-brain barrier restriction. The biochemical CSF parameters showed partial improvement: the albumin ratio decreased, immunoglobulin intrathecal synthesis and oligoclonal bands were no more detectable, but FLC absolute values and indices remained elevated, confirming persisting CSF inflammation. This is the first report on Tocilizumab and steroid treatment effects on FLC concentrations. FLC measurement both in serum and CSF could be useful markers both for diagnosis and evaluation of the response to therapy in the inflammatory and immunological processes of SNC.