Progress in the management and treatment of infected pancreatic necrosis

Differential roles of inflammatory cells in pancreatitis

The incidence of acute pancreatitis per 100,000 of population ranges from 5 to 80. Patients suffering from hemorrhagic-necrotizing pancreatitis die in 10-24% of cases. 80% of all cases of acute pancreatitis are etiologically linked to gallstone disease immoderate alcohol consumption. As of today no specific causal treatment for acute pancreatitis exists. Elevated C-reactive protein levels above 130,mg/L can also predict a severe course of acute pancreatitis. The essential medical treatment for acute pancreatitis is the correction of hypovolemia. Prophylactic antibiotics should be restricted to patients with necrotizing pancreatitis, infected necrosis or other infectious complications. However, as premature intracellular protease activation is known to be the primary event in acute pancreatitis. Severe acute pancreatitis is characterized by an early inflammatory immune response syndrome (SIRS) and a subsequent compensatory anti-inflammatory response syndrome (CARS) contributing to severity as much as protease activation does. CARS suppresses the immune system and facilitates nosocomial infections including infected pancreatic necrosis, one of the most feared complications of the disease. A number of attempts have been made to suppress the early systemic inflammatory response but even if these mechanisms have been found to be beneficial in animal models they failed in daily clinical practice.

Intra-abdominal fungal infections complicating acute pancreatitis: a review

Intra-abdominal infections of pancreatic or peripancreatic necrotic tissue complicate the clinical course of severe acute pancreatitis (SAP) and are associated with significant morbidity. Fungal infection of necrotic pancreatic tissue is increasingly being reported. The incidence of intra-abdominal pancreatic fungal infection (PFI) varies from 5% to 68.5%. Candida albicans is the most frequently isolated fungus in patients with necrotizing pancreatitis. Prolonged use of prophylactic antibiotics, prolonged placement of chronic indwelling devices, and minimally invasive or surgical interventions for pancreatic fluid collections further increase the risk of PFI. Computed tomography- or ultrasound-guided fine-needle aspiration of pancreatic necrosis is a safe, reliable method for establishing pancreatic infection. Amphotericin B appears to be the most effective antifungal treatment. Drainage and debridement of infected necrosis are also critical for eradication of fungi from the poorly perfused pancreatic or peripancreatic tissues where the antifungal agents may not reach to achieve therapeutic levels. Fungal infection adversely affects the outcome of patients with SAP and is associated with increased morbidity, although the mortality rate is not increased specifically because of PFI. Although antifungal prophylaxis has been suggested for patients on broad-spectrum antibiotics, no randomized controlled trials have yet studied its efficacy in preventing PFI.

Minimal access retroperitoneal pancreatic necrosectomy: improvement in morbidity and mortality with a less invasive approach

OBJECTIVE

Comparison of minimal access retroperitoneal pancreatic necrosectomy (MARPN) versus open necrosectomy in the treatment of infected or nonresolving pancreatic necrosis.

SUMMARY OF BACKGROUND DATA

Infected pancreatic necrosis may lead to progressive organ failure and death. Minimal access techniques have been developed in an attempt to reduce the high mortality of open necrosectomy.

METHODS

This was a retrospective analysis on a prospective data base comprising 189 consecutive patients undergoing MARPN or open necrosectomy (August 1997 to September 2008). Outcome measures included total and postoperative ICU and hospital stays, organ dysfunction, complications and mortality using an intention to treat analysis.

RESULTS

Overall 137 patients underwent MARPN versus open necrosectomy in 52. Median (range) age of the patients was 57.5 (18-85) years; 118 (62%) were male. A total of 131 (69%) patients were tertiary referrals, with a median time to transfer from index hospital of 19 (2-76) days. Etiology was gallstones or alcohol in 129 cases (68%); 98 of 168 (58%) patients had a positive culture at the first procedure. Of the 137 patients, 34 (31%) had postoperative organ failure in the MARPN group, and 39 of 52 (56%) in the open group (P<0.0001); 59/137 (43%) versus 40/52 (77%), respectively, required postoperative ICU support (P<0.0001). Of the 137 patients 75 (55%) had complications in the MARPN group and 42 of 52 (81%) in the open group (P=0.001). There were 26 (19%) deaths in the MARPN group and 20 (38%) following open procedure (P=0.009). Age (P<0.0001), preoperative multiorgan failure (P<0.0001), and surgical procedure (MARPN, P=0.016) were independent predictors of mortality.

CONCLUSION

This study has shown significant benefits for a minimal access approach including fewer complications and deaths compared with open necrosectomy.

Effect of 5-FU on modulation of disarrangement of immune-associated cytokines in experimental acute pancreatitis

AIM: To investigate the effects of 5-Fluorouracil (5-FU) on modulation of pro-inflammatory and anti-inflammatory cytokines in acute pancreatitis and the mechanism of it in the treatment of acute pancreatitis.

METHODS: Male Sprague Dawley rats were assigned to 3 Groups: Group A, sham operated rats as controls (n = 7); Group B, acute pancreatitis induced by ductal injection with 5% sodium cholate at a volume of 1.0 mL/kg without any other treatment; Group C, after the pancreatitis was induced as in Group B, the rats were injected intravenously with 5-FU 40 mg/kg. The animals in Groups B and C were killed at 2, 6 and 24 h after operation (n = 7), and blood samples were taken for measurement of tumor necrosis factor-α (TNF-α), interleukin-1 (IL-1), interleukin-6 (IL-6) (by bioassay), and interleukin-10 (IL-10), transforming growth factor-β (TGF-β) (by ELISA). The wet weight of pancreatic tissue, serum amylase levels and white blood cells were also measured.

RESULTS: Four rats in Group B and one in Group C died after pancreatitis was induced. Both pro-inflammatory cytokines (TNF-α, IL-1, IL-6) at the 2 and 6 h period and the anti-inflammatory cytokines (IL-10, TGF-β) at 24 h increased significantly (P < 0.05) in rats of Group B. After treatment with 5-FU, TNF-α, IL-1, and IL-6 in serum of rats of Group C were inhibited at 2 and 6 h after operation (P < 0.05), and IL-10, TGF-β were inhibited at 24 h compared to Group B (P < 0.05). Obvious improvements in the severity of the acute pancreatitis, including the amylase levels, wet weight of pancreatic tissue and neutrophil counts, were also observed after treatment with 5-FU.

CONCLUSION: 5-FU is an anti-metabolic and immunosuppressive agent which can minimize the abnormal immune cytokine response and relieve the pathophysiological disorders associated with experimental acute pancreatitis.

Toward an update of the atlanta classification on acute pancreatitis: review of new and abandoned terms

OBJECTIVES

The 1992 Atlanta classification is a clinically based classification system that defines the severity and complications of acute pancreatitis. The purpose of this review was to assess whether the terms abandoned by the Atlanta classification are really discarded in the literature. The second objective was to review what new terms have appeared in the literature since the Atlanta symposium.

METHODS

We followed a Medline search strategy in review and guideline articles after the publication of the Atlanta classification. This search included the abandoned terms: "phlegmon," "infected pseudocyst," "hemorrhagic pancreatitis," and "persistent pancreatitis."

RESULTS

A total of 239 publications were reviewed, including 10 guideline articles and 42 reviews. The abandoned terms "hemorrhagic pancreatitis" and "persistent pancreatitis" are hardly encountered, in contrast, both "infected pseudocyst" and "phlegmon" are frequently used, and several authors question their abandonment. New terminology in acute pancreatitis consists of "organized pancreatic necrosis," "necroma," "extrapancreatic necrosis," and "central gland necrosis."

CONCLUSIONS

This review demonstrates that the Atlanta classification is still not universally accepted. Several abandoned terms are frequently used, and new terms have emerged that describe manifestations in acute pancreatitis that were not specifically addressed during the Atlanta symposium.

Long-term results and quality of life of patients undergoing sequential surgical treatment for severe acute pancreatitis complicated by infected pancreatic necrosis

BACKGROUND

Infected pancreatic necrosis (IPN) is one of the most severe complications of acute pancreatitis (AP). Sequential surgical debridement represents one of the most effective treatments in terms of morbidity and mortality. The aim of this paper is to describe the quality of life and long-term results (e.g., nutritional, muscular, and pancreatic function) of patients treated by sequential necrosectomy at the Department of Surgery of the University of Insubria (Varese, Italy).

METHODS

Data were collected on patients undergoing sequential surgical debridement as treatment for IPN. The severity of AP was evaluated using the Ranson criteria, the Acute Physiology and Chronic Health Evaluation (APACHE II) Score, and the Sepsis Score, as well as the extent of necrosis. The surgical approach was through a midline or subcostal laparotomy, followed by exploration of the peritoneal cavity, wide debridement, and peritoneal lavage. The abdomen was either left open or closed partially with a surgical zipper, with multiple re-laparotomies scheduled until debridement of necrotic tissue was complete. The long-term evaluation focused on late morbidity, performance status, and abdominal wall function.

RESULTS

In the majority of patients (68%), mixed flora were isolated. Pseudomonas aeruginosa was the microorganism identified most commonly (59%), often associated with Candida albicans or C. glabrata. The mean total hospital stay was 71+/-38 days (range 13-146 days), of which 24+/-19 days (range 0-66 days) were in the intensive care unit. Eight patients died, the deaths being caused by multiple organ dysfunction syndrome in seven patients and hemorrhage from the splenic artery in one. Normal exocrine and endocrine pancreatic function was observed in 28 patients (88%). At discharge, four patients had steatorrhea, which was temporary. Eight patients (23%) developed pancreatic pseudocysts, and in six, cystogastostomy was performed. Most patients (29/32, 91%) developed a post-operative hernia, but only five required surgical repair. All patients had a Short Form (SF)-36 score>60%, and 20 of the 32 patients (68%) had scores>70-80% (good quality of life). The worst scores were related to alcoholic pancreatitis.

CONCLUSIONS

The degree of pancreatic failure (exocrine and endocrine function) is not related to the amount of pancreatic necrosis. Even with a need for repeated laparotomy and multiple surgical procedures, the abdominal wall capacity as well as long-term quality of life remain excellent.

JPN Guidelines for the management of acute pancreatitis: surgical management

Acute pancreatitis represents a spectrum of disease ranging from a mild, self-limited course to a rapidly progressive, severe illness. The mortality rate of severe acute pancreatitis exceeds 20%, and some patients diagnosed as mild to moderate acute pancreatitis at the onset of the disease may progress to a severe, life-threatening illness within 2–3 days. The Japanese (JPN) guidelines were designed to provide recommendations regarding the management of acute pancreatitis in patients having a diversity of clinical characteristics. This article sets forth the JPN guidelines for the surgical management of acute pancreatitis, excluding gallstone pancreatitis, by incorporating the latest evidence for the surgical management of severe pancreatitis in the Japanese-language version of the evidence-based Guidelines for the Management of Acute Pancreatitis published in 2003. Ten guidelines are proposed: (1) computed tomography-guided or ultrasound-guided fine-needle aspiration for bacteriology should be performed in patients suspected of having infected pancreatic necrosis; (2) infected pancreatic necrosis accompanied by signs of sepsis is an indication for surgical intervention; (3) patients with sterile pancreatic necrosis should be managed conservatively, and surgical intervention should be performed only in selected cases, such as those with persistent organ complications or severe clinical deterioration despite maximum intensive care; (4) early surgical intervention is not recommended for necrotizing pancreatitis; (5) necrosectomy is recommended as the surgical procedure for infected pancreatic necrosis; (6) simple drainage should be avoided after necrosectomy, and either continuous closed lavage or open drainage should be performed; (7) surgical or percutaneous drainage should be performed for pancreatic abscess; (8) pancreatic abscesses for which clinical findings are not improved by percutaneous drainage should be subjected to surgical drainage immediately; (9) pancreatic pseudocysts that produce symptoms and complications or the diameter of which increases should be drained percutaneously or endoscopically; and (10) pancreatic pseudocysts that do not tend to improve in response to percutaneous drainage or endoscopic drainage should be managed surgically.

Current management of acute pancreatitis

The incidence of acute pancreatitis varies considerably between regions and is estimated at 5-80 per 100,000 population. The mortality rate of acute edematous-interstitial pancreatitis is below 1%, whereas 10-24% of patients with severe acute pancreatitis die. The early prognostic factors that can be used to determine whether the clinical course is likely to be severe are three or more signs of organ failure according to the Ranson or Imrie scores, the presence of nonpancreatic complications, and the detection of pancreatic necrosis by imaging techniques. Elevated C-reactive protein levels above 130 mg/l can also predict a severe course of acute pancreatitis with high sensitivity. Although no causal treatment exists, replacing the dramatic fluid loss that takes place in the early disease phase is critical and determines the patient's prognosis. Adequate pain relief with opiates is another therapeutic priority. In patients with pancreatic necrosis, the high mortality rate between the third and fourth week after the initial episode is determined largely by the development of pancreatic infection, and can therefore be reduced by early antibiotic treatment. Early enteral nutrition for the treatment of acute pancreatitis has been shown to be superior and much more cost-effective than parenteral nutrition. Infected pancreatic necrosis or pancreatic abscess are two of the few remaining indications for open surgery in acute pancreatitis. Even when indicated, surgery is frequently delayed or even replaced by minimally invasive surgical techniques.

Polymorphism of the TNF-alpha, HSP70-2, and CD14 genes increases susceptibility to severe acute pancreatitis

OBJECTIVES

Proinflammatory cytokines and heat shock proteins play fundamental roles in the pathogenesis of acute pancreatitis. We studied whether polymorphisms of the tumor necrosis factor alpha (TNF-alpha), heat shock protein 70-2 (HSP70-2), and CD14 genes correlate with the severity of acute pancreatitis.

METHODS

Patients with acute pancreatitis (n = 77) of mixed etiology were grouped according to the severity of the disease on the basis of the Ranson scores. Healthy blood donors (n = 71) served as controls. TNF-alpha-308 polymorphism was determined by NcoI RFLP, HSP70-2 polymorphism by PstI RFLP, and CD14-159 polymorphism by melting point analysis.

RESULTS

There was a moderate increase in the frequency of the TNF1/2 genotype (P = 0.046) among patients with severe acute pancreatitis as compared with those with mild disease. A more significant increase was observed in the frequency of the HSP70-2 G allele between groups of patients with mild or severe pancreatitis (18.9% vs. 53%; P < 0.001). Conversely, the A/A genotype was markedly more frequent among the patients with mild pancreatitis (P < 0.0001). There was no significant correlation between CD14-159 promoter polymorphism and the severity of pancreatitis.

CONCLUSION

High frequencies of the HSP70-2 G and the TNF-alpha -308 A alleles were associated with risk of severe acute pancreatitis. Genotype assessments may be important prognostic tools to predict disease severity and the course of acute pancreatitis. Therefore, genotype assessments may also be used to guide treatment or to identify risk populations for severe acute pancreatitis.

Medical treatment of acute pancreatitis

Eighty percent of all cases of acute pancreatitis are linked etiologically to gallstone disease or caused by immoderate alcohol consumption. No specific causal treatment for acute pancreatitis exists. Early prognostic factors that indicate severe disease are three or more signs on organ failure scores according to Ranson, Imrie, or Acute Physiology and Chronic Health Evaluation (APACHE) 11, extrapancreatic complications of the disease, or the detection of pancreatic necrosis on CT scans. Elevated CRP levels above 130 mg/L can also predict a severe course of acute pancreatitis. The essential medical treatment for acute pancreatitis is the correction of hypovolemia. Moreover, relief of often severe visceral pain is a high priority. Prophylactic antibiotics should be restricted to patients with necrotizing pancreatitis, infected necrosis, or other infectious complications. Enteral nutrition has no adverse effect compared with parenteral nutrition during the course of acute pancreatitis, and is probably beneficial in regard to outcome.

Pancreatic fungal infection

INTRODUCTION

There has been a steady rise in the incidence of pancreatic fungal infections. Even though fungal infections of the pancreas are not very common, they are often nosocomial.

AIMS

To review pancreatic fungal infections and to compare their clinical characteristics with those of bacterial pancreatic infections, along with the causes and approaches to diagnosis and treatment.

RESULTS

Because of the lack of randomized, prospective trials, standardized recommendations for use of antifungal prophylaxis would be premature. The most important aspect of prophylaxis against pancreatic fungal infection is minimizing the factors that predispose the pancreas to fungal infections.

CONCLUSION

Isolation of fungal elements from necrotic pancreatic tissue and treatment of local infection are vital. Treatment of local candidal infection should be initiated with surgical necrosectomy. Systemic antifungal therapy should be started early in the course of the disease, but whether antifungal agents should be added to the prophylactic antibiotic regimens for patients with necrotizing pancreatitis remains questionable.

Laparoscopic pancreatic necrosectomy

We describe a patient with infected pancreatic necrosis who was treated successfully with minimally invasive surgery. Five weeks after an episode of acute uncomplicated pancreatitis, he was found to have infected pancreatic necrosis and splenic vein thrombosis. The patient underwent a laparoscopic pancreatic necrosectomy, splenectomy, and cholecystectomy. Seven days after surgery, the patient was discharged and continued to be asymptomatic for the 6 months of follow-up.

Pancreatic surgery

According to epidemiologic studies, the incidence of acute and chronic pancreatitis and carcinoma of the pancreas are increasing worldwide. This is the result not only of improved diagnostic methods introduced in the last decades (eg, contrast-enhanced computed tomography, "all-in-one" magnetic resonance imaging, single-photon emission computed tomography, and endoscopic retrograde cholangiopancreatography) but also of changes in the environment and nutritional behavior. Once a specific diagnosis has been made, the first-choice interventions in acute and chronic inflammatory pancreatic diseases are predominantly organ-and organ function-preserving surgical procedures. In pancreatic cancer, extended radical surgery and multimodal therapies seem to offer the most benefit. This article provides an overview of recently published articles focusing on surgical treatment options in acute and chronic pancreatitis and carcinoma of the pancreas.

Leucocyte activation markers in clinical practice

The response against tissue injury and infection begins with the early activation of molecular and cellular elements of the inflammatory and immune response. Severe tissue injury, necrosis, and infection induce imbalanced inflammation associated with leukocyte over-stimulation and excessive or dysregulated release of cellular mediators. Clinical and experimental studies have shown that these mediators are directly related to progressive post-injury complications. Persistent increased levels of pro-inflammatory mediators produce tissue injury. Excessive production and activity of anti-inflammatory mediators cause anergy and/or immune dysfunction with increased susceptibility to infection. Leukocyte activation is assessed by cell surface phenotype expression, cellular mediators determination, or by measuring functional responses using isolated cells. Potential routine clinical uses are: evaluation of severity and prognosis in critically ill patients, immunomonitoring of sepsis, and detection of tissue injury, necrosis, and infection. In practice, the determination of cellular activation markers is restricted by a limited number of automated methods and by the cost of reagents. The availability of flow cytometry and immunoassay automated systems can contribute to a wider use in practice. Here we review the immunopathophysiology of polymorphonuclear neutrophil, monocyte, macrophage, and lymphocyte activation in response to tissue injury and infection. In addition, laboratory methods for their determination, and clinical applications in practice, are discussed.