Interventional strategies in infected necrotizing pancreatitis: Indications, timing, and outcomes

Abstract

Acute pancreatitis (AP) is one of the most common gastrointestinal diseases and remains a life-threatening condition. Although AP resolves to restitutio ad integrum in approximately 80% of patients, it can progress to necrotizing pancreatitis (NP). NP is associated with superinfection in a third of patients, leading to an increase in mortality rate of up to 40%. Accurate and early diagnosis of NP and associated complications, as well as state-of-the-art therapy are essential to improve patient prognoses. The emerging role of endoscopy and recent trials on multidisciplinary management of NP established the "step-up approach". This approach starts with endoscopic interventions and can be escalated to other interventional and ultimately surgical procedures if required. Studies showed that this approach decreases the incidence of new multiple-organ failure as well as the risk of interventional complications. However, the optimal interventional sequence and timing of interventional procedures remain controversial. This review aims to summarize the indications, timing, and treatment outcomes for infected NP and to provide guidance on multidisciplinary decision-making.

Keywords: Acute necrotizing pancreatitis; Endoscopy; Necrosis; Pancreatitis; Superinfection; Surgery.

Figure 1

Mortality rates of acute pancreatitis and pathomechanisms. The mortality rate of all patients with acute pancreatitis (AP) is less than 10%. One-fifth of the patients developed necrotizing AP by ATP depletion, MLKL phosphorylation, acinar cell necroptosis, and/or acinar cell necrosis. One-third of the patients with necrotizing AP developed bacterial or fungal infection. The mortality rate of the infected necrotizing pancreatitis is up to 39%.

Figure 2

Endoscopic transluminal drainage with plastic stenting. A: A typical computed tomography (CT) scan with walled-off necrosis (WON) formed by necrotizing pancreatitis (white arrow shows stomach and yellow dotted line is the demarcation line of the WON); B: Endoscopic ultrasonography (EUS)-guided drainage for WON was performed (orange arrow shows the needle of 22-gauge EUS needle); C: Two plastic stents and nasobiliary drainage tube was placed into the WON; D: The size of the WON was reduced in the CT scan one month after the procedure. WON: Walled-off necrosis.

Figure 3

A case with endoscopic transluminal drainage with lumen-apposing metal stent. A: Computed tomography (CT) scan before performing the endoscopic ultrasonography (EUS)-guided drainage (White arrow shows the stomach and the yellow arrow shows the walled-off necrosis (WON); the yellow dotted line is the demarcation line of the WON); B: EUS (with color doppler) picture shows marked echoic lesion without vessels; C: Lumen-apposing metal stent (LAMS) and nasobiliary drainage tube were placed (white arrow shows LAMS: Hot AXIOS^TM 15 mm × 10 mm, Boston Scientific, Marlborough, MA, United States; Boston Scientific Japan, Tokyo, Japan); D: Esophagogastroduodenoscopy was inserted into necrotic cavity through LAMS; E: Necrosectomy was performed using endoscopic retrieval net; F: Endoscopic findings of the WON one month after the multiple necrosectomy sessions (2-3 times/wk); G: CT scan shows marked reduction of WON cavity one month after multiple necrosectomy sessions. WON: Walled-off necrosis; LAMS: Lumen-apposing metal stent.

Figure 4

Overview of the step-up approaches of infected necrotizing pancreatitis patients. In the acute phase, multidisciplinary treatment for acute pancreatitis is recommended. Endoscopic necrosectomy or surgical step-up should be considered if there no clinical improvement is observed within 72 h. Open necrosectomy should be considered after video-assisted retroperitoneal debridement or minimal access retroperitoneal pancreatic necrosectomy. ETN: Endoscopic transluminal necrosectomy; STE: Sinus tract endoscopy; ETD: Endoscopic transluminal drainage; PCD: Percutaneous catheter drainage; VARD: Video-assisted retroperitoneal debridement; MARPN: Minimal access retroperitoneal pancreatic necrosectomy.