Indications and outcomes of enterovesical and colovesical fistulas: systematic review of the literature and meta-analysis of prevalence.

Background: Entero-colovesical fistula is a rare complication of various benign and malignant diseases. The diagnosis is prominently based on clinical symptoms; imaging studies are necessary not only to confirm the presence of the fistula, but more importantly to demonstrate the extent and the nature of the fistula. There is still a lack of consensus regarding the if, when and how to repair the fistula. The aim of the study is to review the different surgical treatment options, focus on surgical indications, and explore cumulative recurrence, morbidity, and mortality rates of entero-vesical and colo-vesical fistula patients.

Methods: A systematic review of the literature was conducted according to PRISMA guidelines. Random effects meta-analyses of proportions were developed to assess primary and secondary endpoints. I statistic and Cochran's Q test were computed to assess inter-studies' heterogeneity.

Results: Twenty-two studies were included in the analysis with a total of 861 patients. Meta-analyses of proportions pointed out 5, 22.2, and 4.9% rates for recurrence, complications, and mortality respectively. A single-stage procedure was performed in 75.5% of the cases, whereas a multi-stage operation in 15.5% of patients. Palliative surgery was performed in 6.2% of the cases. In 2.3% of the cases, the surgical procedure was not specified. Simple and advanced repair of the bladder was performed in 84.3% and 15.6% of the cases respectively.

Conclusions: Although burdened by a non-negligible rate of complications, surgical repair of entero-colovesical fistula leads to excellent results in terms of primary healing. Our review offers opportunities for significant further research in this field. Level of Evidence Level III according to ELIS (SR/MA with up to two negative criteria).