Walled-off necrosis: safety of watchful waiting

Asymptomatic pancreatic necrosis should be managed conservatively, regardless of its extent. However, late sequelae and safety of non-interventional management in patients with asymptomatic walled-off necrosis remain unclear.

The purpose of this study was to report the clinical outcome of outpatient expectant management in a cohort of patients with walled-off necrosis who were discharged asymptomatic after an episode of acute pancreatitis.

Sixteen patients with walled-off necrosis asymptomatic at discharge were identified retrospectively from a single institution. Data were analyzed for the type of complications, their incidence and treatment.

Seven of 16 patients (44 %) did not experience any complications during a median follow-up of 17 months. Nine of 16 patients (56 %) became symptomatic or developed complications within a median follow-up of 49 days after discharge. The most common complication was infection of pancreatic necrosis which occurred in 7 of 9 patients. Six of these patients were successfully treated with minimally invasive techniques. In 5 of 7 patients, infection of necrosis was due to oral commensal bacteria. Acute intracavitary hemorrhage and intractable abdominal pain developed in one patient each. There was no mortality in this series.

Outpatient watchful waiting can be used safely in patients with asymptomatic walled-off necrosis, although nearly half of them eventually develop complications which require interventional treatment. Most late infections of pancreatic necrosis are probably due to a blood-borne transmission of oral commensal bacteria.