Serum and cerebrospinal fluid cytokines in children with acute encephalopathy.

The pathogenesis of acute encephalopathy (AE) remains unclear, and a biomarker has not been identified. Levels of 49 cytokines and chemokines, including osteopontin (OPN), were measured in serum and cerebrospinal fluid (CSF) of children with AE (n = 17) or febrile convulsion (FC; n = 8; control group). The AE group included acute necrotizing encephalopathy (n = 1), acute encephalopathy with biphasic seizures and late reduced diffusion (AESD; n = 3), clinically mild encephalitis/encephalopathy with a reversible splenial lesion (MERS; n = 4), and unclassified acute encephalopathy (UCAE; n = 9) that does not meet the criteria of syndrome classification. Five individuals with AE had neurological sequelae or death (poor prognosis), whereas 12 were alive without neurological sequelae (good prognosis). The CSF:serum ratios of OPN, CC chemokine ligand (CCL)4, and interleukin (IL)-10 were significantly higher in AE than in FC. The CSF levels of macrophage inhibitory factor (MIF) and leukemia inhibitory factor (LIF) were significantly higher in the poor-prognosis group than in the good-prognosis group. The CSF:serum ratios of OPN were significantly higher in AESD and in MERS than in FC. The CSF:serum ratios of MIF and OPN were higher in MERS than in UCAE or FC. Our results suggest that microglia-related cytokines and chemokines such as OPN, MIF, and LIF could be novel biomarkers of AE, in addition to the previously reported IL-10 and CCL4, and that MIF and LIF may be markers of poor prognosis.