Early therapeutic plasma exchange may lead to complete neurological recovery in moderate to severe influenza-associated acute necrotizing encephalopathy.

BACKGROUND

Acute necrotizing encephalopathy (ANE) is a pediatric neurological disease, presumably caused by cytokine storms, with a poor prognosis. Immunomodulatory therapy, including therapeutic plasma exchange (TPE), could be an effective treatment.

CASES

Two patients with influenza-associated ANE were treated. The ANE severity scores were 3 and 8 in case 1 (a 3-y-old boy) and case 2 (a 7-y-old boy), respectively. In case 1, intravenous methylprednisolone and TPE were initiated at 8 and 16 h, respectively, after the onset of impaired consciousness. In case 2, multiple organ failure and septic shock persisted even after infusion of fluids and inotropic agents. Intravenous methylprednisolone and TPE were started at 5 and 9 h, respectively, after the onset of impaired consciousness, which improved the inotrope-refractory septic shock. Patient 1 and 2 achieved complete neurological recovery within 4 weeks and after 3 months, respectively. In both patients, cytokine levels were serially measured. There were increased serum interleukin (IL)-6 and IL-10 levels in both patients; patient 1 showed increased IL-6 levels in the initial cerebrospinal fluid sample. There was a post-treatment decrease in serum IL-6 levels in both cases.

DISCUSSION

Early intensive immunomodulatory therapy with TPE may improve neurological outcomes in pediatric influenza-associated ANE. Further studies are required to establish the efficacy of TPE for ANE.