Gastrointestinal norovirus infection associated with exacerbation of inflammatory bowel disease

In this study we aimed to determine, in pediatric patients, whether norovirus infection could be associated with exacerbations of inflammatory bowel disease (IBD) and ascertain whether the clinical expression of norovirus gastroenteritis was similar in patients with IBD compared with non-IBD controls.

We performed a case-control retrospective chart review, over a 10-month interval, of patients with IBD with an exacerbation of their disease. The presence of norovirus in stool and/or rectal swab samples, as determined by an enzyme-linked immunoassay, was assessed. In addition, sex, age, type of IBD, presence or absence of diarrhea, hematochezia, and the need for hospitalization were determined. A similar number of control patients who did not have IBD were used as controls.

Nine patients with IBD (8 ulcerative colitis/1 Crohn disease) had exacerbations with diarrhea. Eight had norovirus antigen in at least 1 sample. All 9 patients with IBD presented with bloody diarrhea and 6 of the 8 norovirus-positive patients with IBD required hospitalization. All of the control patients experienced diarrhea; however, no hematochezia was noted and no hospitalization was required. Several patients with IBD and controls remained positive for norovirus months after the initial positive stool and/or rectal swab sample. The virus appeared to be more common during winter months.

We conclude that norovirus may be associated with exacerbations of IBD. When norovirus accompanies IBD it is more likely to be associated with hematochezia than when the infection occurs in the absence of IBD.