Analysis of hospitalizations due to intussusception in Sicily in the pre-rotavirus vaccination era (2003-2012)

Background: Intussusception is the most common cause of bowel obstruction in infants with an incidence ranging from 9-328 cases per 100,000 infants aged 0-11 months. Causes underlining this clinical manifestation are still unknown. Possible relationship with a withdrawn tetravalent rotavirus vaccine was not confirmed by post-licensure studies and actually no increased risk of intussusception was found between infants vaccinated with both the recently licensed rotavirus vaccines. Aim of this study is to analyze the intussusception hospitalizations in Sicily from 2003 to 2012 before the introduction of rotavirus universal vaccination and its possible relation with rotavirus gastroenteritis trend. Methods: Were collected data from hospital discharge records occurred from 1^st January 2003 to 31^st December 2012 in Sicily. Intussusception cases were defined as all hospitalizations with an ICD-9-CM code of 560.0 on any discharge diagnoses. As a proxy for the severity of cases were considered ICD-9-CM procedure codes accounting for surgical or radiologic reduction. Results: A total of 340 intussusception cases were hospitalized in Sicily from 2003 to 2012 in children aged 0-59 months. 46.8 % occurred in the age class 0-11 months. Hospitalization rate for intussusception was 11.4 cases per 100,000 per year (32.6 cases per 100,000 among 0-11 months children; 7.3 cases per 100,000 among 12-59 months children), with a M:F sex ratio of 1.8. During hospitalization only 25 % of intussusceptions had a spontaneous resolution, 56.5 % of cases required a surgical intervention. From 2003 to 2012 intussusception cases were equally distributed during the year without any seasonality, while gastroenteritis hospitalizations due to rotavirus infection have a typically late winter and spring distribution. Conclusions: In Sicily from 2003 to 2012 hospitalizations due to intestinal invagination were higher among children aged 0-11 months with observed rates similar to other European countries. Regional baseline data analysis of intussusception among 0-59 children is recognized as an evidence-based public health strategy by international health authorities. Indeed, this strategy is necessary to compare any post-licensure age or sex-related change in intussusception trend after universal rotavirus vaccination introduction.