Patients with infected pancreatic necrosis (IPN) are more likely to experience organ failure and mortality, which makes identifying them as quickly as possible especially crucial. A new study aimed to make this task a bit easier by categorizing the main risk factors for IPN in a cohort of patients with severe acute pancreatitis, which included extensive spread of necrotic collections, preceding bacteremia, and preceding open abdomen treatment, as well as postinterventional pancreatitis.
In their study, published in the Journal of Gastrointestinal Surgery, Henrik L. Husu, MD, of the University of Helsinki, and colleagues noted the inherent challenges of rendering a preoperative diagnosis of IPN.
“Fever and increasing inflammation markers may indicate suspicion of IPN, but these are very common in patients with severe acute pancreatitis treated in the ICU,” and more knowledge of specific IPN risk factors is needed to improve clinical decision-making, they said.
Dr. Husu and colleagues identified 163 adults with acute pancreatitis admitted to the ICU at a single center between 2010 and 2018, approximately 68% of whom had alcoholic necrotizing pancreatitis. Pneumonia, bacteremia, and IPN occurred at an average of 4, 16, and 23 days, respectively, after ICU admission.
Forty-seven patients (28.8%) developed IPN within 90 days of ICU admission, all patients had a least one persistent organ failure, and 60% had multiple organ failure within 24 hours of ICU admission.
In a multivariate regression analysis, independent risk factors for IPN included postoperative or postendoscopic retrograde cholangiopancreatography (ERCP) pancreatitis (odds ratio,13.5) and widespread necrotic collections (OR, 5.7 for unilateral paracolic or retromesenteric; OR, 21.8 for bilateral paracolic or unilateral paracolic and retromesenteric). Other risk factors were preceding bacteremia (OR, 4.8) and preceding open abdomen treatment for abdominal compartment syndrome (OR, 3.6).
After 90 days, 29 patients had died, including 7 with IPN and 22 without IPN. In addition, patients with IPN had longer overall hospital stays and ICU stays, higher rates of ICU readmission, and greater use of open necrosectomy, the researchers noted.
The study findings were limited by several factors, including the retrospective design, lack of controls, potential differences in treatment protocols, and the survival bias that prevented direct comparison of mortality in patients with and without IPN, the researchers noted. “This study cannot provide a reliable estimate of the difference in mortality attributable to IPN itself.”
However, the researchers noted that “the strength of the present study was to include only patients with persistent organ failure and admission to ICU in the early disease course,” and results indicate a significant morbid outcome associated with IPN. “In attempting to decrease the rate of IPN, efforts to identify and treat incipient organ failure with subsequent low threshold for admission to ICU becomes essential,” they emphasized.
More data may prompt greater intervention
“IPN portends a poor prognosis, and can be challenging to both diagnose and treat,” Gyanprakash A. Ketwaroo, MD, of Baylor College of Medicine, Houston, said in an interview. “Identifying risk factors for development of IPN may facilitate earlier therapy that could modify the natural history of this disease.”
Dr. Ketwaroo said he was not surprised by the study findings. “This was a small single-center, retrospective study, where infection could only be ascertained among those who received interventions, and the findings should thus be interpreted within these limitations. Overall, however, I was not surprised. More extensive necrosis and opportunities for infectious seeding of necrosis such as interventions (ERCP) and bacteremia would be expected risk factors. I was surprised by the use of prophylactic antibiotics, as well as the high rate of open necrosectomy, though this should not affect the main findings of risk factors for infection.
“The studies highlight that a significant portion of patients with severe acute pancreatitis with necrosis will develop infection,” said Dr. Ketwaroo. “Being aware of the risk factors for infection, as identified in this study, can add to our clinical judgment in suspecting infection and opting for debridement. Especially with advancements in endoscopic necrosectomy, gastroenterologists may be more inclined to intervene when suspecting IPN. The next steps for research are to validate risk factors in larger, prospective studies.”
The study was supported by governmental competitive funds for medical research, a research grant from the Medical Society of Finland, and a research grant from Perkléns Foundation. The researchers had no financial conflicts to disclose. Dr. Ketwaroo had no financial conflicts to disclose but is a member of the GI & Hepatology News editorial advisory board.