Correspondence

Norovirus Gastroenteritis

N Engl J Med 2010; 362:557-558February 11, 2010

Article

To the Editor:

As Glass et al. discuss in their review article (Oct. 29 issue),1 norovirus is the major cause of epidemic gastroenteritis and the most common cause of diarrhea in adults. Prospective studies have shown that 3 to 36% of enteric infections lead to a new diagnosis of the irritable bowel syndrome,2 one of the most common gastrointestinal disorders seen in primary care and specialist practice. A recent meta-analysis of nine prospective cohort studies showed that intestinal infection was associated with an increase by a factor of six in the odds ratio for the irritable bowel syndrome.3 Although pathogenic bacteria have been identified in most studies as etiologic factors in postinfectious cases of the irritable bowel syndrome, recent data have indicated the involvement of other infectious agents, including viruses.2 A 2-year prospective cohort study analyzed an outbreak of severe gastroenteritis attributed to a foodborne norovirus.4 At 3 months, the prevalence of postinfectious irritable bowel syndrome was significantly higher in subjects with acute gastroenteritis than in control subjects. Furthermore, a trend toward increased risk was observed at 6, 12, and 24 months. Larger prospective, controlled studies are awaited to confirm that norovirus gastroenteritis could be one of the most relevant etiologic factors in the irritable bowel syndrome.

Cesare Cremon, M.D.
Roberto De Giorgio, M.D., Ph.D.
Giovanni Barbara, M.D.
University of Bologna, Bologna, Italy
cesare.cremon@aosp.bo.it

No potential conflict of interest relevant to this letter was reported.

4 References

1. 1

   Glass RI, Parashar UD, Estes MK. Norovirus gastroenteritis. N Engl J Med 2009;361:1776-1785
   Full Text | Web of Science | Medline

2. 2

   Spiller R, Garsed K. Postinfectious irritable bowel syndrome. Gastroenterology 2009;136:1979-1988
   CrossRef | Web of Science | Medline

3. 3

   Thabane M, Kottachchi DT, Marshall JK. Systematic review and meta-analysis: the incidence and prognosis of post-infectious irritable bowel syndrome. Aliment Pharmacol Ther 2007;26:535-544
   CrossRef | Web of Science | Medline

4. 4

   Marshall JK, Thabane M, Borgaonkar MR, James C. Postinfectious irritable bowel syndrome after a food-borne outbreak of acute gastroenteritis attributed to a viral pathogen. Clin Gastroenterol Hepatol 2007;5:457-460
   CrossRef | Web of Science | Medline

Author/Editor Response

Cremon et al. note that the irritable bowel syndrome can occur in the aftermath of an episode of infectious diarrhea, often linked to a bacterial pathogen, and ask whether noroviruses might be associated with this condition. In the study that they cite,1 at 3 months of follow-up, symptoms associated with the irritable bowel syndrome were reported by 21 of 89 Canadian gastroenterology nurses (23.6%) who were affected by a viral gastroenteritis outbreak, as compared with only 1 of 29 nurses (3.4%) who remained well. Although a definitive cause was not established, the clinical and epidemiologic features were consistent with Kaplan's criteria to assess outbreaks due to norovirus in the absence of laboratory confirmation.2 Khan et al. documented norovirus infection in eight of nine pediatric patients with exacerbation of the irritable bowel syndrome,3 and Lencioni et al. found that murine norovirus infection enhanced disease progression in a mouse model of inflammatory bowel disease.4 Well-designed studies are warranted to establish the veracity of these intriguing findings linking norovirus with the irritable bowel syndrome. If confirmed, it could improve our understanding of the pathogenesis and long-term treatment of patients with this syndrome. The confirmation of such a relation to inflammatory bowel disease would also lead us to look more carefully for long-term effects of norovirus gastroenteritis, which is currently thought to be merely an acute event.

Roger I. Glass, M.D., Ph.D.
National Institutes of Health, Bethesda, MD

Umesh D. Parashar, M.D., M.P.H.
Centers for Disease Control and Prevention, Atlanta, GA

Mary K. Estes, Ph.D.
Baylor College of Medicine, Houston, TX

Since publication of their article, the authors report no further potential conflict of interest.

4 References

1. 1

   Marshall JK, Thabane M, Borgaonkar MR, James C. Postinfectious irritable bowel syndrome after a food-borne outbreak of acute gastroenteritis attributed to a viral pathogen. Clin Gastroenterol Hepatol 2007;5:457-460
   CrossRef | Web of Science | Medline

2. 2

   Turcios RM, Widdowson MA, Sulka AC, Mead PS, Glass RI. Reevaluation of epidemiological criteria for identifying outbreaks of acute gastroenteritis due to norovirus: United States, 1998-2000. Clin Infect Dis 2006;42:964-969
   CrossRef | Web of Science | Medline

3. 3

   Khan RR, Lawson AD, Minnich LL, et al. Gastrointestinal norovirus infection associated with exacerbation of inflammatory bowel disease. J Pediatr Gastroenterol Nutr 2009;48:328-333
   CrossRef | Web of Science | Medline

4. 4

   Lencioni KC, Seamons A, Treuting PM, Maggio-Price L, Brabb T. Murine norovirus: an intercurrent variable in a mouse model of bacteria-induced inflammatory bowel disease. Comp Med 2008;58:522-533
   Web of Science | Medline