Clinical characteristics and treatment of severe encephalitis associated with neurogenic pulmonary edema caused by enterovirus 71 in China

Background: Hand-foot-mouth disease has become a major public health issue in children in China. In the present prospective study we investigated the clinical characteristics and emergency management of children with severe encephalitis associated with NPE caused by enterovirus 71.

Methods: The study was conducted in 2 pediatric intensive care units (PICUs) over a 2-month period. Clinical records were reviewed of critically ill children with severe encephalitis associated with NPE caused by EV71 who were admitted to PICUs during the period of May to June 2008 in Fuyang.

Results: We reviewed the complete records of 36 children, of whom 23 (63.9%) were male and 13 (36.1%) female. Their age ranged from 4 to 48 months, with an average of 15.8 months. All children except one were under 3 years of age. The overall mortality in these children was 19.4%. The average duration of critical life threatening signs and symptoms was 2.1 days (12 hours-5 days). Nervous system diseases included brainstem encephalitis in 27 children (75%), brainstem encephalitis associated with myelitis in 6 children (16.7%), and general encephalitis in 3 chidren (8.3%), respectively. In 12 patients of NPE (33.3%) pink or bloody bubble sputum and asymmetric pulmonary edema or hemorrhage was the primary manifestation but no typical exanthema was observed. Five children died of acute onset of NPE and / or pulmonary hemorrhage with rapid progression of cardiopulmonary failure within hours after admission. Therapeutic management consisted of mechanical ventilation and administration of mannitol, methylprednisolone, intravenous immunoglobulin (IVIG) and vasoactive drugs, associated with the need of fluid volume resuscitation in 9 (25%) of the 36 children.

Conclusions: In children less than 3 years of age found to be affected by severe EV71 encephalitis associated with NPE, one fifth may die. The major organ systems infected by severe EV71 include the central nervous system, the respiratory system, and the cardiovascular system. Early diagnosis and evaluation, respiratory support, treatment of intracranial hypertension, and mainttenance of function of the cardiovascular system are the most important therapeutic measures.