Isolated peripancreatic necrosis (PPN) is associated with better clinical outcomes compared with combined pancreatic and peripancreatic involvement (CPN)- a systematic review and meta-analysis

Background and aims: Peripancreatic necrosis (PPN) is considered as a distinct entity with a better outcome when compared with combined pancreatic and peripancreatic necrosis (CPN), but there is no systematic review to summarize the evidence. Our study aimed to perform a meta-analysis of existing observational studies comparing the outcomes of PPN with CPN. Methods: Studies in adult patients comparing the outcomes of PPN and CPN from PubMed, Medline, and Scopus databases from inception to November 2018 were systematically searched. The primary outcome was mortality, and secondary outcomes included multi-organ failure, persistent organ failure, infected necrosis, need for interventions including open necrosectomy. Pooled adjusted odds ratios, and 95% confidence intervals (CI) were obtained by the random-effects model. Forrest plots were constructed to show the summary pooled estimate. Heterogeneity was assessed by using I2 measure of inconsistency. Results: A total of 6 studies involving 1851 patients (1295 (70%) with CPN and 556 (30%) with PPN) were included. Patients with CPN had a significantly higher mortality (OR 2.49, 95% CI: 1.61–3.87), risk for multi-organ failure (OR 3.24, 95% CI: 2.38–4.43), persistent organ failure (OR 2.79, 95% CI: 1.53–5.08), and infected necrosis (OR 6.21, 95% CI: 3.85–10.03). They underwent more interventions (OR 5.86, 95% CI: 3.69–9.32), including open necrosectomy (OR 5.04, 95% CI: 3.33–7.63). Heterogeneity was low (I2 = 18.1, p = 0.296), and there was no publication bias. Conclusion: Isolated peripancreatic necrosis portends an overall better prognosis when compared to necrosis involves pancreatic parenchyma. Clinicians should recognize this distinction for management decisions.