Objective: The objective of the study was to define the characteristics and microbiology of persistent diarrhea (PD) in US children.
Methods: Six-month prospective cohort study of a convenience sample of 604 healthy 6- to 36-month-old children recruited by the Slone Center Office-based Research Network.
Results: Of 611 diarrhea episodes, 50 (8.2%) lasted ≤ 14 days. The incidence of PD was 0.18 episodes per person-year, and the median duration of episodes was 22.0 days (range, 14-64 days). PD episodes were more likely than acute episodes to result in a medical visit (28.0% vs 8.2%; P = 0.0001). The most commonly used treatments were oral rehydration solution (12.0% of episodes) and antibiotics (6.0%). No bacterial or parasitic pathogens were associated with PD; but norovirus, rotavirus and sapovirus were each significantly more prevalent in PD stools compared with baseline stools, with relative risks of 12.4, 6.9 and 6.2, respectively. Fifty-nine per cent of the PD specimens tested were negative for all studied pathogens.
Conclusions: PD occurs with a frequency of approximately 1 case per 5 person-years in US infants and young children. It seems to be a generally benign illness, with only 28% of cases presenting to medical care. Although viral pathogens seem to cause a minority of PD episodes in this population, most are not due to currently known infectious agents.
*Slone Epidemiology Center at Boston University, Boston, MA; †GRASP Digestive Diseases Research Center, Tufts-New England Medical Center, Boston, MA; and ‡University of Maryland School of Medicine, Baltimore, MD
Received February 1, 2006; accepted April 5, 2006.
Address correspondence and reprint requests to Louis Vernacchio, MD, MSc, Slone Epidemiology Center at Boston University, 1010 Commonwealth Ave, Boston, MA 02115. (e-mail: email@example.com).
Supported by funding from a United States Department of Agriculture Cooperative State, Research, Education, and Extension Service Grant (USDA 00-35212) and by a supplement from the Tufts GRASP Digestive Disease Center (NIDDK P30-DK-034928).
Dr. Acheson is now with the US Food and Drug Administration.