LAUSR

BACKGROUND Acute encephalitis and encephalopathy are life-threatening diseases in children. However, no laboratory examinations are performed for their early diagnosis and treatment. Alpha 2-macroglobulin (α2M) is a blood glycoprotein that increases during the early stages of inflammation. In the present study, we investigated the role of α2M levels in acute encephalitis and encephalopathy. METHODS We analyzed the cerebrospinal fluid and serum samples from patients with acute disseminated encephalomyelitis, infection-related acute encephalopathy, febrile status epilepticus, and febrile seizure simplex type. Samples were collected from the pediatric department of hospitals throughout the Fukushima Prefecture between January 1, 1999, and May 31, 2012. RESULTS α2M levels in the cerebrospinal fluid were 4.7 (3.8-8.4) μg/mL for acute disseminated encephalomyelitis, 2.1 (1.1-2.3) μg/mL for infection-related acute encephalopathy, 1.1 (0.9-6.4) μg/mL for febrile status epilepticus, and 1.0 (0.8-1.1) μg/mL for febrile seizure simplex type. α2M levels in patients with acute disseminated encephalomyelitis were significantly higher than those in patients with infection-related acute encephalopathy and febrile seizure simplex type (P = 0.019 and P = 0.002, respectively). The ratio of α2M level in the cerebrospinal fluid to that in the serum in patients with acute disseminated encephalomyelitis was significantly higher than the ratio in patients with febrile status epilepticus (P = 0.04). In patients with acute disseminated encephalomyelitis, α2M levels in the cerebrospinal fluid decreased with treatment. CONCLUSIONS Our results suggest that α2M levels in the cerebrospinal fluid reflect the neuroinflammatory status of patients with acute disseminated encephalomyelitis.