A multi-country study of intussusception in children under 2 years of age in Latin America: analysis of prospective surveillance data

Hospital del Ni?o. Infectious Disease Department. Ciudad de Panam?, Panama. Instituto Mexicano del Seguro Social. Medical Research Unit on Infectious Diseases. CMN-SXXI. Mexico City, Mexico. Centro de Estudios en Infectologia Pediatrica. Clinica Materno Infantil Los Farallones. Cali, Colombia. Universidad Nacional Aut?noma de Nicaragua. Edificio Central. Le?n, Nicaragua. Minist?rio da Sa?de. Secretaria de Vigil?ncia em Sa?de. Instituto Evandro Chagas. Ananindeua, PA, Brasil. Hospital Dr. Humberto Notti. Villa Nueva de Guaymall?n, Mendoza, Argentina Universidad de Concepci?n. Concepci?n, Chile. Universidad de Concepci?n. Concepci?n, Chile. Universidad de Valpara?so. Escuela de Medicina. Valpara?so, Chile. Hospital Nacional de Ni?os. Paseo Col?n, San Jos?, Costa Rica. Organizaci?n para el Desarrollo y la Investigaci?n Salud en Honduras. Colonia Humuya, Tegucigalpa, Honduras. Hospital General de Tlanepantla ?Valle Ceyl?n?. Tlanepantla, Mexico. Hospital Infantil de Mexico. Calle Dr. M?rquez . M?xico DF, Mexico / Ministry of Health. National Center for Child and Adolescent Health. Colonia Merced Gomez, Mexico DF, Mexico. Instituto Nacional de Pediatr?a. M?xico DF, Mexico. Instituto Nacional de Ciencias M?dicas y Nutrici?n Salvador Zubir?n. Mexico DF, Mexico. Hospital Maternidad Nuestra Sra de la Altagracia. Santo Domingo, DN, Rep?blica Dominicana. Fundaci?n para el Avance de la Investigaci?n Cl?nica y Translacional, Consultorios M?dicos Am?rica. V?a Espa?a, Carrasquilla, Panama / GlaxoSmithKline Vaccines. Clayton, Panama. GlaxoSmithKline Vaccines M?xico. M?xico DF, Mexico. GlaxoSmithKline Vaccines Argentina. Buenos Aires, Argentina / Independent Medical Professional. Buenos Aires, Argentina. GlaxoSmithKline Vaccines Costa Rica. San Jose, Costa Rica / GlaxoSmithKline Vaccines. Ciudad del Saber, Clayton, Panama. GlaxoSmithKline Vaccines. Philadelphia, USA / Merck & Co., Global Health Outcomes Vaccines. Philadelphia, PA, USA. GlaxoSmithKline Vaccines. Rixensart, Belgium / Philadelphia Department of Public Health. Philadelphia, USA. GlaxoSmithKline Vaccines. Rixensart, Belgium / P95 Excellence in Pharmacovigilance and Epidemiology, Leuven, Belgium. GlaxoSmithKline Vaccines. Rixensart, Belgium / GlaxoSmithKline Vaccines, Parc de la Noire Epine. Wavre, Belgium. Background: Intussusception (IS) is a form of acute intestinal obstruction that occurs mainly in infants and is usually of unknown cause. An association between IS and the first licensed rotavirus vaccine, a reassortanttetravalent, rhesus-based rotavirus vaccine (RRV-TV), led to the withdrawal of the vaccine. New rotavirus vaccines have now been developed and extensively studied for their potential association with IS. This study aimed to describe the epidemiology and to estimate the incidence of IS in Latin American infants prior to new vaccine introduction. Methods: Children under 2 years of age representing potential IS cases were enrolled in 16 centers in 11 Latin American countries from January 2003 to May 2005. IS cases were classified as definite, probable, possible or suspected as stated on the Brighton Collaboration Working Group guidelines. Results: From 517 potential cases identified, 476 (92 per cent) cases were classified as definite, 21 probable, 10 possible and 10 suspected for intussusception. Among the 476 definite IS cases, the median age at presentation was 6.4 months with 89 per cent of cases aged 1 year. The male to female ratio was 1.5:1. The incidence of definite IS per 100,000 subject-years ranged from 1.9 in Brazil to 62.4 in Argentina for children 2 years of age, and from 3.8 in Brazil to 105.3 in Argentina for children aged 1 year. Median hospital stay was 4 days with a high prevalence of surgery as the primary treatment (65 per cent). Most cases (88 per cent) made a complete recovery, but 13 (3 per cent) died. No clear seasonal pattern of IS cases emerged. Conclusions: This study describes the epidemiology and estimates the incidence of IS in Latin American infants prior to the introduction of new rotavirus vaccines. The incidence of IS was found to vary between different countries, as observed in previous studies.