Intussusception surveillance in a rural demographic surveillance area in bangladesh.

BACKGROUND Rotavirus is the leading cause of diarrhea-related morbidity and mortality in developing countries, including Bangladesh. The licensed vaccine Rotashield was withdrawn from the market because of an increased risk of intussusception. This study was undertaken to estimate the background incidence rates of intussusception among children aged <2 years, using retrospective and prospective studies in a rural demographic surveillance area in Bangladesh. METHODS All hospital charts of children aged <2 years who presented to the Matlab Hospital and 2 other treatment centers of the International Centre for Diarrhoeal Disease Research, Bangladesh (ICDDR,B), during January 2001-August 2004 were reviewed retrospectively. A prospective surveillance was performed from August 2004 through December 2006 at the 3 treatment centers of ICDDR,B serving Matlab, 4 district and subdistrict government hospitals, and 3 district-based private clinics, to determine population-based rates of intussusception with use of Brighton Collaboration case definitions. All suspected cases of intussusception were referred to the Matlab Hospital by community health research workers for further assessment by a trained medical officer, including performance of an ultrasound examination. RESULTS In total, 2856 charts of children aged <2 years were reviewed retrospectively, and 4 probable cases and 19 possible cases of intussusception were identified. In the prospective surveillance, of 1508 potential cases, including 41 referred by community health research workers, only 2 cases met the case definition of probable intussusception, and 1 case met the definition of possible intussusception. A total of 123 patients had ultrasound examinations performed. The population-based rates of probable and possible cases of intussusception among children aged <2 years were 0-17.8 and 17.7-81.7 cases per 100,000 children per year, respectively. In the retrospective and prospective surveillance, the rates were 0-18.7 and 0-97 cases per 100,000 children per year, respectively. CONCLUSIONS The incidence of intussusception was low among children in Bangladesh. A surveillance system for intussusception has been fully established in the Matlab surveillance area to diagnose, treat, and refer potential cases. This study provides useful information for detection of intussusception during future studies of new-generation rotavirus vaccines and also provides background incidence rates for comparison when rotavirus vaccines are introduced.