Norovirus: A possible cause of pneumatosis intestinalis

OBJECTIVE: Pneumatosis intestinalis (PI) in children is associated with immunosuppression, mucosal disruption from trauma, obstructive pulmonary disease, congenital heart disease, and gastrointestinal infections. Our study is the first report of norovirus infection-associated PI. PATIENTS AND METHODS: A retrospective review was performed in pediatric patients (older than 30 days) with PI from March 2005 to April 2009. Since December 2008, in addition to routine stool examinations, reverse-transcriptase polymerase chain reaction testing for calicivirus (norovirus and sapovirus), adenovirus, astrovirus, and enterovirus has been performed. RESULTS: Twenty-seven patients with PI were identified. The median age was 1.4 (range 0.2-14.8 years). Seventeen patients (63.0%) were immunocompromised hosts. Pathogens were identified in 5 immunocompromised patients (5/27 and 5/8 since December 2008). Of note, norovirus was identified in 4 patients (80%, 4/5) during the cold weather season. The genotype of noroviruses in these patients was GII-4. Among 27 patients with PI, 10 patients (37.0%) developed PI in the spring and 11 (40.7%) in the winter. Twenty-four patients survived (88.9%, 24/27). None of the patients with norovirus or rotavirus infection died. CONCLUSIONS: Our data suggest that norovirus infection may contribute to the development of PI in immunocompromised hosts.