Bacterial infection and extent of necrosis are determinants of organ failure in patients with acute necrotizing pancreatitis

Guidelines for Antibiotics Prescription in Critically Ill Patients

How to cite this article: Khilnani GC, Tiwari P, Mittal S, Kulkarni AP, Chaudhry D, Zirpe KG, et al. Guidelines for Antibiotics Prescription in Critically Ill Patients. Indian J Crit Care Med 2024;28(S2):S104-S216.

Predicting the severity of acute pancreatitis: Current approaches and future directions

Acute pancreatitis (AP) is a sudden-onset inflammatory disease of the pancreas. The severity of AP is classified into mild, moderate, and severe categories based on the presence and persistence of organ failure. Severe acute pancreatitis (SAP) can be associated with significant morbidity and mortality. It requires early recognition for appropriate timely management. Prognostic scores for predicting SAP incorporating many clinical, laboratory, and radiological parameters have been developed in the past. However, all of these prognostic scores have low positive predictive value for SAP and some of these scores require >24 h for assessment. There is a need to develop biomarkers that can accurately identify patients at risk for SAP early in the course of the presentation. In this review, we aim to provide a summary of the most commonly utilized prognostic scores for AP and discuss future directions.

Epidemiology and risk factors for mortality in critically ill patients with pancreatic infection

Background

The AbSeS-classification defines specific phenotypes of patients with intra-abdominal infection based on the (1) setting of infection onset (community-acquired, early onset, or late-onset hospital-acquired), (2) presence or absence of either localized or diffuse peritonitis, and (3) severity of disease expression (infection, sepsis, or septic shock). This classification system demonstrated reliable risk stratification in intensive care unit (ICU) patients with intra-abdominal infection. This study aimed to describe the epidemiology of ICU patients with pancreatic infection and assess the relationship between the components of the AbSeS-classification and mortality.

Methods

This was a secondary analysis of an international observational study ("AbSeS") investigating ICU patients with intra-abdominal infection. Only patients with pancreatic infection were included in this analysis (n=165). Mortality was defined as ICU mortality within 28 days of observation for patients discharged earlier from the ICU. Relationships with mortality were assessed using logistic regression analysis and reported as odds ratio (OR) and 95% confidence interval (CI).

Results

The overall mortality was 35.2% (n=58). The independent risk factors for mortality included older age (OR=1.03, 95% CI: 1.0 to 1.1 P=0.023), localized peritonitis (OR=4.4, 95% CI: 1.4 to 13.9 P=0.011), and persistent signs of inflammation at day 7 (OR=9.5, 95% CI: 3.8 to 23.9, P<0.001) or after the implementation of additional source control interventions within the first week (OR=4.0, 95% CI: 1.3 to 12.2, P=0.013). Gram-negative bacteria were most frequently isolated (n=58, 49.2%) without clinically relevant differences in microbial etiology between survivors and non-survivors.

Conclusions

In pancreatic infection, a challenging source/damage control and ongoing pancreatic inflammation appear to be the strongest contributors to an unfavorable short-term outcome. In this limited series, essentials of the AbSeS-classification, such as the setting of infection onset, diffuse peritonitis, and severity of disease expression, were not associated with an increased mortality risk.ClinicalTrials.gov number: NCT03270345.

Recent advances in the role of neutrophils and neutrophil extracellular traps in acute pancreatitis

Pancreatitis is an inflammatory disease, which is triggered by adverse events in acinar cells of the pancreas. After the initial injury, infiltration of neutrophils in pancreas is observed. In the initial stages of pancreatitis, the inflammation is sterile. It has been shown that the presence of neutrophils at the injury site can modulate the disease. Their depletion in experimental animal models of the acute pancreatitis has been shown to be protective. But information on mechanism of contribution to inflammation by neutrophils at the injury site is not clear. Once at injury site, activated neutrophils release azurophilic granules containing proteolytic enzymes and generate hypochlorous acid which is a strong microbicidal agent. Additionally, emerging evidence shows that neutrophil extracellular traps (NETs) are formed which consist of decondensed DNA decorated with histones, proteases and granular and cytosolic proteins. NETs are considered mechanical traps for microbes, but there is preliminary evidence to indicate that NETs, which constitute a special mechanism of the neutrophil defence system, play an adverse role in pancreatitis by contributing to the pancreatic inflammation and distant organ injury. This review presents the overall current information about neutrophils and their role including NETs in acute pancreatitis (AP). It also highlights current gaps in knowledge which should be explored to fully elucidate the role of neutrophils in AP and for therapeutic gains.

Clinical significance of reactive thrombocytosis in the course of acute pancreatitis

BACKGROUND

Reactive thrombocytosis occurs secondary to systemic infections, inflammatory, and other conditions. The relationship between thrombocytosis and acute pancreatitis (AP) in inflammatory diseases is uncertain. This study aimed to evaluate the clinical significance of thrombocytosis in AP patients during hospitalization.

METHODS

Subjects within 48 h of AP onset were consecutively enrolled over 6 years. Platelet counts of ≥ 450,000/µL were defined as thrombocytosis, < 100,000/µL as thrombocytopenia, and other counts as normal. We compared clinical characteristics, including the rate of severe AP (SAP) assessed by the Japanese Severity Score; blood markers, including hematologic and inflammatory factors and pancreatic enzymes during hospitalization; and pancreatic complications and outcomes in the three groups.

RESULTS

A total of 108 patients were enrolled. Although, SAP was more common in patients with thrombocytosis and thrombocytopenia (87.9% and 100%, respectively), the differences in lymphocytes and C-reactive protein, lactase dehydrogenase, and antithrombin levels, which are factors of the systemic inflammatory response, and the mean platelet volume, an indicator of platelet activation, were observed among patients with thrombocytosis and thrombocytopenia during hospitalization. Regarding pancreatic complications and outcomes, patients with thrombocytosis and thrombocytopenia had higher acute necrotic collection (ANC), pancreatic necrosis, intestinal paralysis, respiratory dysfunction, and pancreatic-related infection levels than patients with normal platelet levels. The relationship between pancreatic complications and thrombocytosis was assessed by multivariate logistic regression; the odds ratios for development of ANC, pancreatic necrosis and pancreatic-related infections were 7.360, 3.735 and 9.815, respectively.

CONCLUSIONS

Thrombocytosis during hospitalization for AP suggests development of local pancreatic complications and pancreatic-related infections.

Early prediction of the severe course, survival, and ICU requirements in acute pancreatitis by artificial intelligence

OBJECTIVE

To evaluate the success of artificial intelligence for early prediction of severe course, survival, and intensive care unit(ICU) requirement in patients with acute pancreatitis(AP).

METHODS

Retrospectively, 1334 patients were included the study. Severity is determined according to the Revised Atlanta Classification(RAC). The success of machine learning(ML) method was evaluated by 13 simple demographic, clinical, etiologic, and laboratory features obtained on ER admission. Additionally, it was evaluated whether Balthazar-computerized tomography severity index(CTSI) at 48-h contributed to success. The dataset was split into two parts, 90% for ML(of which 70% for learning and 30% for testing) and 10% for validation and 5-fold stratified sampling has been utilized. Variable Importance was used in the selection of features during training phase of machine. The Gradient Boost Algorithm trained the machine by KNIME analytics platform. SMOTE has been applied to increase the minority classes for training. The combined effects of the measured features were examined by multivariate logistic regression analysis and reciever operating curve curves of the prediction and confidence of the target variables were obtained.

RESULTS

Accuracy values for the early estimation of Atlanta severity score, ICU requirement, and survival were found as 88.20%, 98.25%, and 92.77% respectively. When Balthazar-CTSI score is used, results were found as 91.02%, 92.25%, and 98% respectively.

CONCLUSIONS

The ML method we used successfully predicted the severe course, ICU requirement and survival, with promising accuracy values of over 88%. If 48-h Balthazar-CTSI is included in the calculation, the severity score and survival rates increase even more.

Clinical characteristics and risk factors of organ failure and death in necrotizing pancreatitis

BACKGROUND

Organ failure (OF) and death are considered the most significant adverse outcomes in necrotizing pancreatitis (NP). However, there are few NP-related studies describing the clinical traits of OF and aggravated outcomes.

PURPOSE

An improved insight into the details of OF and death will be helpful to the management of NP. Thus, in our research, we addressed the risk factors of OF and death in NP patients.

METHODS

We performed a study of 432 NP patients from May 2017 to December 2021. All patients with NP were followed up for 36 months. The primary end-points were risk factors of OF and death in NP patients. The risk factors were evaluated by logistic regression analysis.

RESULTS

NP patients with OF or death patients were generally older, had a higher APACHE II score, longer hospital stay, longer ICU stay, as well as a higher incidence of severe acute pancreatitis (SAP), shock and pancreatic necrosis. Independent risk factors related to OF included BMI, APACHE II score and SAP (P < 0.05). Age, shock and APACHE II score (P < 0.05) were the most significant factors correlated with the risk of death in NP patients. Notably, increased mortality was linked to the number of failed organs.

CONCLUSIONS

NP is a potentially fatal disease with a long hospital or ICU stay. Our study indicated that the incidence of OF and death in NP patients was 69.9% and 10.2%, respectively. BMI, SAP, APACHE II score, age and shock are potential risk factors of OF and death in NP patients. Clinicians should focus on these factors for early diagnosis and appropriate therapy.

Diagnosis and Treatment of Acute Pancreatitis

The pancreas is a glandular organ that is responsible for the proper functioning of the digestive and endocrine systems, and therefore, it affects the condition of the entire body. Consequently, it is important to effectively diagnose and treat diseases of this organ. According to clinicians, pancreatitis—a common disease affecting the pancreas—is one of the most complicated and demanding diseases of the abdomen. The classification of pancreatitis is based on clinical, morphologic, and histologic criteria. Medical doctors distinguish, inter alia, acute pancreatitis (AP), the most common causes of which are gallstone migration and alcohol abuse. Effective diagnostic methods and the correct assessment of the severity of acute pancreatitis determine the selection of an appropriate treatment strategy and the prediction of the clinical course of the disease, thus preventing life-threatening complications and organ dysfunction or failure. This review collects and organizes recommendations and guidelines for the management of patients suffering from acute pancreatitis.

The clinical outcome from early versus delayed minimally invasive intervention for infected pancreatic necrosis: a systematic review and meta-analysis

BACKGROUND

While the management of infected pancreatic necrosis (IPN) has evolved in the last two decades with the adoption of minimally invasive interventions (drainage ± debridement), it is unknown whether the principle of delaying intervention inherited from the open surgery era still applies. The aim of the current study was to investigate the impact of the timing of minimally invasive intervention on the outcomes of patients with IPN requiring intervention.

METHODS

PubMed, Embase, MEDLINE and Web of Science databases were searched for appropriate studies. The primary outcome of interest was hospital mortality, the secondary outcomes were the incidence of complications during the hospitalization, including new-onset organ failure, gastrointestinal fistula or perforation, bleeding and length of hospital or intensive care unit (ICU) stay.

RESULTS

Seven clinical studies were included with a total of 742 patients with IPN requiring intervention, of whom 321 received early intervention and 421 delayed intervention. Results from the meta-analysis showed that early minimally invasive intervention did not increase hospital mortality (odds ratio 1.65, 95% confidence interval 0.97-2.81; p = 0.06) but was associated with a remarkably prolonged hospital stay and an increased incidence of gastrointestinal fistula or perforation when compared with delayed intervention.

CONCLUSIONS

Although no firm conclusion can be drawn because of the quality of available studies, it does appear that timing of intervention is a risk factor for adverse outcomes and ought to be investigated more rigorously in prospective studies.

Acute necrotising pancreatitis: measurements of necrosis volume and mean CT attenuation help early prediction of organ failure and need for intervention

OBJECTIVES

This study explored the early predictive value of volume and mean CT density of necrosis for adverse outcomes in patients with acute necrotising pancreatitis (ANP).

METHODS

A total of 155 patients with ANP who underwent CECT within 7 days of symptom onset were included. The necrosis volume, mean CT density, and modified CT severity index (mCTSI) were calculated. C-reactive protein (CRP) and blood urea nitrogen (BUN) levels both 48 h after symptom onset were reviewed. Adverse outcomes were recorded. The predictive value of each indicator was assessed using ROC curve analysis.

RESULTS

There were significant associations between necrosis volume and mean CT density and organ failure (OF), persistent OF (POF), and need for intervention (p < 0.001 for all). For predicting OF, the area under the curve (AUC) was significantly higher for necrosis volume than for mCTSI and BUN (AUC: 0.84 vs 0.67, p = 0.0011; 0.84 vs 0.71, p = 0.0193, respectively). For predicting POF and need for intervention, the AUCs for necrosis volume were significantly higher than those for mCTSI (AUC: 0.79 vs 0.66, p = 0.0045; 0.77 vs 0.61, p = 0.0019, respectively), but did not significantly differ from those for CRP and BUN. For predicting OF, a significantly better predictive value was achieved with mean CT density than with mCTSI (AUC: 0.79 vs 0.67, p = 0.0163). There were no significant differences in predictive value between mean CT density, CRP, and BUN.

CONCLUSIONS

The volume and mean CT density of necrosis based on CECT can provide early prediction of OF, POF, and need for intervention.

KEY POINTS

• Compared to mCTSI, necrosis volume might be used to more accurately diagnose organ failure and persistent organ failure and might be better associated with the need for intervention. • Necrosis volume and mean CT density based on CECT are reliable quantitative predictors for organ failure, persistent organ failure, and intervention in acute pancreatitis.

Occurrence and Risk Factors of Infected Pancreatic Necrosis in Intensive Care Unit-Treated Patients with Necrotizing Severe Acute Pancreatitis

BACKGROUND

In patients with severe acute pancreatitis (SAP), infected pancreatic necrosis (IPN) is associated with a worsened outcome. We studied risk factors and consequences of IPN in patients with necrotizing SAP.

METHODS

The study consisted of a retrospective cohort of 163 consecutive patients treated for necrotizing SAP at a university hospital intensive care unit (ICU) between 2010 and 2018.

RESULTS

All patients had experienced at least one persistent organ failure and approximately 60% had multiple organ failure within the first 24 h from admission to the ICU. Forty-seven (28.8%) patients had IPN within 90 days. Independent risk factors for IPN were more extensive anatomical spread of necrotic collections (unilateral paracolic or retromesenteric (OR 5.7, 95% CI 1.5-21.1) and widespread (OR 21.8, 95% CI 6.1-77.8)) compared to local collections around the pancreas, postinterventional pancreatitis (OR 13.5, 95% CI 2.4-76.5), preceding bacteremia (OR 4.8, 95% CI 1.3-17.6), and preceding open abdomen treatment for abdominal compartment syndrome (OR 3.6, 95% CI 1.4-9.3). Patients with IPN had longer ICU and overall hospital lengths of stay, higher risk for necrosectomy, and higher readmission rate to ICU.

CONCLUSIONS

Wide anatomical spread of necrotic collections, postinterventional etiology, preceding bacteremia, and preceding open abdomen treatment were identified as independent risk factors for IPN.

Minimal-access retroperitoneal pancreatic necrosectomy for infected necrotizing pancreatitis: a multicentre study of a step-up approach

BACKGROUND

Various minimally invasive approaches have been described for infected necrotizing pancreatitis. This article describes a modified minimal-access retroperitoneal pancreatic necrosectomy (MARPN) procedure assisted by gas insufflation.

METHODS

This retrospective, observational study documented patients who had undergone a step-up MARPN between 1 January 2010 and 31 December 2016. A minimum follow-up of 1 year was required for inclusion. The step-up approach involved percutaneous catheter drainage followed by the modified MARPN and necrosectomy. If more than one access site was needed it was categorized as complex MARPN.

RESULTS

Of 212 patients with infected necrotizing pancreatitis, 164 (77·4 per cent) underwent a step-up approach. The median number of percutaneous catheter drains and MARPN procedures was 3 (range 1-7) and 1 (1-6) respectively. Ninety patients (54·9 per cent) underwent complex MARPN. For residual necrosis after MARPN, three patients (1·8 per cent) underwent sinus tract gastroscopy, and 11 (6·7 per cent) had sinography combined with a tube change. However, operations in 13 patients (7·9 per cent) required conversion to open surgery. Postoperative complications developed in 103 patients (62·8 per cent). The mortality rate was 6·1 per cent (10 deaths).

CONCLUSION

A step-up approach using a modified MARPN for infected necrotizing pancreatitis is a reasonable option.

Factors associated with mortality in patients with infected pancreatic necrosis: the "surgery effect"

Severe acute pancreatitis complicated by infection is associated with high mortality. Invasive treatment is indicated in the presence of infected (suspected) pancreatic and/or peripancreatic necrosis (IPN) in the absence of response to intensive medical support. Step-up approach (SUA) has been demonstrated to lower complication rate compared to upfront open surgery. However, this approach has not been associated with lower mortality, and no factors have been studied that could help to identify the high risk patients. In this study, we aimed to analyse those factors associated with mortality following the invasive treatment of IPN, focusing on the role of surgical necrosectomy. A retrospective and observational study based on a multicentre prospective database was conducted. The database was coordinated by the Hospital General Universitario de Alicante, Spain and the Spanish Association of Pancreatology. Demographics, clinical data, and laboratory and imaging findings were collected. Atlanta 2012 criteria were considered to classify acute necrotizing pancreatitis and for the definition of IPN. Step-up approach was used in all centres with the intention of avoiding surgery whenever possible. Surgical necrosectomy was performed by open approach. From January 2013 to October 2014, a total of 1655 patients with the diagnosis of acute pancreatitis were included in our database. 1081 were recruited for the final analysis. Out of them, 205 (19%) were classified into acute necrotizing pancreatitis. 77 (8.3%) patients underwent invasive treatment of INP and were included in our study. Overall mortality was 29.9%. Upfront endoscopic or percutaneous drainage was performed in 60 (77.9%) patients and mortality was 26.6%. Out of 60, 22 (36.6%) patients subsequently received rescue surgery; mortality in rescue surgery group was 18.3%. Upfront surgery was carried out in 17 (22.1%) patients; mortality in this group was 41%. At univariate analysis, surgical necrosectomy, extrapancreatic infection, immunosuppression and de-novo haemodialysis were associated with mortality. At multivariate analysis, only surgical necrosectomy was significantly associated with mortality (p = 0.002 OR 3.89). Surgical approach for IPN is associated with high mortality rate. However, these data should be interpreted with caution, since we are not able to assess whether this occurs due to the need of surgery as the only resort when the other approaches are not feasible or fail.

Continuous regional arterial infusion versus intravenous administration of the protease inhibitor nafamostat mesilate for predicted severe acute pancreatitis: a multicenter, randomized, open-label, phase 2 trial

BACKGROUND

Continuous regional arterial infusion (CRAI) of protease inhibitor nafamostat mesilate (NM) is used in the context of predicted severe acute pancreatitis (SAP) to prevent the development of pancreatic necrosis. Although this therapy is well known in Japan, its efficacy and safety remain unclear.

METHODS

This investigator-initiated and -driven, multicenter, open-label, randomized, controlled trial (UMIN000020868) enrolled 39 patients with predicted SAP and low enhancement of the pancreatic parenchyma on computed tomography (CT). Twenty patients were assigned to the CRAI group, while 19 served as controls and were administered NM at the same dose intravenously (IV group). The primary endpoint was the development of pancreatic necrosis as determined by CT on Day 14, judged by blinded central review.

RESULTS

There was no difference between the CRAI and IV groups regarding the percentages of participants who developed pancreatic necrosis (more than 1/3 of the pancreas: 25.0%, range 8.7-49.1% vs. 15.8%, range 3.4-39.6%, respectively, P = 0.694; more than 2/3 of the pancreas: 20%, range 5.7-43.7% vs. 5.3%, range 0.1-26.0%, respectively, P = 0.341). The early analgesic effect was evaluated based on 24-h cumulative fentanyl consumption and additional administration by intravenous patient-controlled analgesia. The results showed that the CRAI group used significantly less analgesic. There were two adverse events related to CRAI, namely bleeding and splenic infarction.

CONCLUSIONS

CRAI with NM did not inhibit the development of pancreatic necrosis although early analgesic effect of CRAI was superior to that of IV. Less-invasive IV therapy can be considered a viable alternative to CRAI therapy.

Percutaneous Endoscopic Step-Up Therapy Is an Effective Minimally Invasive Approach for Infected Necrotizing Pancreatitis

BACKGROUND

Infected pancreatic necrosis (IPN) is a major complication of acute pancreatitis (AP), which may require necrosectomy. Minimally invasive surgical step-up therapy is preferred for IPN.

AIM

To assess the effectiveness of percutaneous endoscopic step-up therapy in patients with IPN and identify predictors of its success.

METHODS

Consecutive patients with AP hospitalized to our tertiary care academic center were studied prospectively. Patients with IPN formed the study group. The treatment protocol for IPN was percutaneous endoscopic step-up approach starting with antibiotics and percutaneous catheter drainage, and if required necrosectomy. Percutaneous endoscopic necrosectomy (PEN) was performed using a flexible endoscope through the percutaneous tract under conscious sedation. Control of sepsis with resolution of collection(s) was the primary outcome measure.

RESULTS

A total of 415 patients with AP were included. Of them, 272 patients had necrotizing pancreatitis and 177 (65%) developed IPN. Of these 177 patients, 27 were treated conservatively with antibiotics alone, 56 underwent percutaneous drainage alone, 53 required underwent PEN as a step-up therapy, 1 per-oral endoscopic necrosectomy, and 52 required surgery. Of the 53 patients in the PEN group, 42 (79.2%) were treated successfully-34 after PEN alone and 8 after additional surgery. Eleven of 53 patients died due to organ failure-7 after PEN and 4 after surgery. Independent predictors of mortality were > 50% necrosis and early organ failure.

CONCLUSION

Percutaneous endoscopic step-up therapy is an effective strategy for IPN. Organ failure and extensive pancreatic necrosis predicted a suboptimal outcome in patients with infected necrotizing pancreatitis.

CT angiographic changes in dogs with acute pancreatitis: A prospective longitudinal study

Computed tomographic angiography (CTA) has recently been shown to be a useful tool in the diagnosis of acute canine pancreatitis, the identification of pancreatic necrosis, and the detection of sequelae. Evidence of pancreatic necrosis on CTA has been shown to be correlated with a poorer outcome in both humans and dogs and early diagnosis and intervention may improve outcomes. In humans, pancreatic necrosis is typically evident on CTA within 48 h of clinical signs, thus, repeat CTA examinations are often performed to identify pancreatic necrosis that may not have been evident on CTA examinations performed early in the course of disease. Published information investigating the timing of CTA examinations and the use of serial CTA in dogs with acute pancreatitis is lacking. In this prospective, longitudinal study, CTA examinations were performed at the time of hospitalization and repeated 3-5 days later in 11 dogs suffering from acute canine pancreatitis to determine if pancreatic necrosis or sequelae are under diagnosed on examinations performed at the time of hospitalization. Computed tomographic angiography studies were evaluated for changes in pancreatic size, pancreatic contrast enhancement, and peri-pancreatic tissues and vessels. The only statistically significant difference between the initial and repeat CTA examinations was the improvement of fat stranding on the repeat CTA examinations (P < .045). Based on these results, CTA performed at the time of admission is likely adequate in the diagnosis and evaluation of dogs with acute pancreatitis. Repeat CTA examinations are unlikely to add additional information in the absence of worsening clinical signs.

Lavage through percutaneous catheter drains in severe acute pancreatitis: Does it help?A randomized control trial

AIMS

There is no study comparing large volume lavage through image guided percutaneously placed drains in severe acute pancreatitis.

METHODS

Of the 114 randomized patients, 60 eligible candidates were randomly allocated to - Lavage Treatment (LT) group (28 patients) and Dependent Drainage (DD) group (32 patients). Primary end point was reversal of pre-existing organ failure, development of new onset organ failure, need for surgery, mortality and hospital stay.

RESULTS

Both the groups were comparable in terms of demographic data, onset and severity of pancreatitis. LT group had higher infected pancreatic necrosis (75% vs 50%,p = 0.047). On intention to treat analysis, lavage treatment group showed a significant reversal of persistent organ failure (84% vs 50%, p = 0.23), reduction in APACHEII scores (3.5 ± 3.405 vs 1.16 ± 3.811 p = 0.012), as measured at the time of placement of PCD to cessation of intervention. There was no difference in development of new onset organ failure in the two groups (25% vs37.5% p=.290). 75% in LT group and 69% in DD group improved with PCD alone. There was no difference in the catheter related complications and number of catheters used. The need for surgical intervention was comparable in two groups (18.8% vs 14.3% p=.737). There was a trend toward decreased mortality in group A (18.8% vs 28.8% p=.370).

CONCLUSION

Large volume lavage trough PCD improves organ failure and this translates into trend towards reduced mortality.

Predrainage and Postdrainage Prognostic Nomograms to Predict Outcome of Percutaneous Drainage for Infected Pancreatic and Peripancreatic Necrotic Collections

OBJECTIVES

This study aimed to identify factors affecting outcome of percutaneous catheter drainage (PCD) in management of infected pancreatic necrosis treated with step-up approach.

METHODS

This was a single-center retrospective cohort study that included patients with infected necrosis undergoing PCD as initial intervention. Patients who did not respond underwent necrosectomy. Predictors of PCD failure (ie, mortality or need for necrosectomy) were analyzed. Models were constructed for predrainage and postdrainage use and were internally validated.

RESULTS

Of 304 patients included, catheter drainage was successful in 59.8%, with overall mortality of 22%. Predrainage model consisted of Acute Physiologic and Chronic Health Evaluation II score at admission, early organ failure, and pancreatic necrosis of greater than 50%. Postdrainage model consisted of Acute Physiologic and Chronic Health Evaluation II at first PCD, early organ failure, pancreatic necrosis of greater than 50%, sepsis reversal within 1 week of PCD and Escherichia coli in PCD culture. Both models were internally validated with area under receiver operating characteristics curve of 71.2% for pre-PCD and 81.2% for post-PCD model. Prognostic nomograms were constructed using the models.

CONCLUSIONS

Percutaneous catheter drainage alone was successful in 59.8% with mortality of 22%. The nomograms can help in guiding treatment strategy and referral of high-risk cases.

A Novel Antifungal Plasma-Activated Hydrogel

Antifungal hydrogels with added antifungal drugs have received extensive attention from researchers due to their potential use in various applications, such as wound dressings and ultrasound gel pads. In this study, we proposed and designed an alternative antifungal hydrogel preparation strategy to obtain hydrogels with high antifungal abilities. We employed plasma-activated water (PAW) instead of water in the hydrogel polymerization process to prepare plasma-activated hydrogels (PAHs). Disc diffusion assay results revealed that PAH exhibits satisfactory antifungal activity. Interestingly, the oxidation-reduction potential (ORP) of the PAH was significantly lower than that of conventional polyacrylamide (PAAm) hydrogels, and we provided a possible reaction equation to explain the lower value of ORP in the PAH. Furthermore, using electron spin resonance (ESR) spectroscopy, the hydroxyl radical was detected in PAHs. Although the active ingredients in the hydrogel cannot be quantitatively measured, the hydroxyl radical and NO₃^- are speculated to be the main components of PAH with antifungal activity according to ESR spectroscopy and optical emission spectroscopy. Further experiments also showed that PAH has a longer antifungal lifetime than PAW. In summary, the proposed plasma-activated hydrogels can provide valuable preparation strategies for delivering antifungal capabilities and have many potential applications in biomedical fields.

Organ Failure Due to Systemic Injury in Acute Pancreatitis

Acute pancreatitis may be associated with both local and systemic complications. Systemic injury manifests in the form of organ failure, which is seen in approximately 20% of all cases of acute pancreatitis and defines "severe acute pancreatitis." Organ failure typically develops early in the course of acute pancreatitis, but also may develop later due to infected pancreatic necrosis-induced sepsis. Organ failure is the most important determinant of outcome in acute pancreatitis. We review here the current understanding of the risk factors, pathophysiology, timing, impact on outcome, and therapy of organ failure in acute pancreatitis. As we discuss the pathophysiology of severe systemic injury, the distinctions between markers and mediators of severity are highlighted based on evidence supporting their causality in organ failure. Emphasis is placed on clinically relevant end points of organ failure and the mechanisms underlying the pathophysiological perturbations, which offer insight into potential therapeutic targets to treat.

Infected Pancreatic Necrosis due to Multidrug-Resistant Organisms and Persistent Organ failure Predict Mortality in Acute Pancreatitis

Background

Organ failure determines outcome in acute pancreatitis (AP). It is controversial if infected pancreatic necrosis (IPN) is also an independent determinant of mortality. We hypothesized that the predictors of mortality in AP might have changed with advances in management and consequent decline in mortality over the past decades. Our objective was to study the predictors of mortality in patients with AP.

Methods

Consecutive patients with a first episode of AP hospitalized from January 2015 to December 2016 were included in an observational study. Patients with IPN were treated with a conservative first approach followed by intervention. Necrosectomy, if required, was delayed beyond 4 weeks and done primarily employing minimally invasive techniques. The primary outcome measure was independent predictors of in-hospital mortality.

Results

Of 209 patients with AP, 81 (39%) had persistent organ failure (OF) and 108 (52%) developed IPN. Overall, 46/209 (22%) patients died. Independent predictors of mortality were OF (odds ratio [OR]19; 95% CI: 6.1–58.8), and IPN due to infection with multidrug resistant (MDR) organisms (OR: 8.4; 95% CI:3.1–22.5). Infected pancreatic necrosis by itself was not found to be a significant predictor of mortality (OR 2; 95% CI: 0.4–9.5).

Conclusion

Persistent OF and complicated IPN due to MDR infection were independent predictors of mortality in patients with AP. Renewed efforts to prevent MDR infection with antibiotic stewardship and strategies for early control of sepsis are urgently required.

The microbiology of infected pancreatic necrosis

BACKGROUND

Acute pancreatitis (AP) continues to cause significant morbidity and mortality, especially when it leads to infected pancreatic necrosis (IPN). Modern treatment of IPN frequently involves prolonged courses of antibiotics in combination with minimally invasive therapies. This study aimed to update the existing evidence base by identifying the pathogens causing IPN and therefore aid future selection of empirical antibiotics.

METHODS

Clinical data, including microbiology results, of consecutive patients with IPN undergoing minimally invasive necrosectomy at our institution between January 2009 and July 2016 were retrospectively reviewed.

RESULTS

The results of 40 patients (22 males and 18 females, median age 60 years) with IPN were reviewed. The etiology of AP was gallstones, alcohol, dyslipidemia and unknown in 31, 2, 2 and 5 patients, respectively. The most frequently identified microbes in microbiology cultures were Enterococcus faecalis and faecium (22.5% and 20.0%) and Escherichia coli (20.0%). In 19 cases the cultures grew multiple organisms. The antibiotics with the least resistance amongst the microbiota were teicoplanin (5.0%), linezolid (5.6%), ertapenem (6.5%), and meropenem (7.4%).

CONCLUSION

The carbapenem antibiotics, ertapenem and meropenem provide good antimicrobial cover against the common, mainly enteral, microorganisms causing IPN. Culture and sensitivity results of acquired samples should be regularly reviewed to adjust prescribing and monitor for emergence of resistance.

Early (<4 Weeks) Versus Standard (≥ 4 Weeks) Endoscopically Centered Step-Up Interventions for Necrotizing Pancreatitis

OBJECTIVES

Current guidelines for necrotizing pancreatitis (NP) recommend delay in drainage ± necrosectomy until 4 or more weeks after initial presentation to allow collections to wall off. However, evidence of infection with clinical deterioration despite maximum support may mandate earlier (<4 weeks) intervention. There are concerns, but scant data regarding risk of complications and outcomes with early endoscopic intervention. Our aim was to compare the results of an endoscopic centered step-up approach to NP when initiated before versus 4 or more weeks.

METHODS

All patients undergoing intervention for NP were managed using an endoscopically centered step-up approach, with transluminal drainage whenever feasible, ±necrosectomy, and/or percutaneous catheter drainage as needed, with surgery only for failures. Interventions were categorized as early or standard based on timing of intervention (<4 weeks or ≥ 4 weeks from onset of pancreatitis). Demographic data, indications and timing for interventions, number and type of intervention, mortality and morbidity (length of stay in hospital and ICU) and complications were compared.

RESULTS

Of 305 patients with collections associated with NP, 193 (63%) (median age-52 years) required intervention, performed by a step-up approach. Of the 193 patients, 76 patients underwent early and 117 patients standard intervention. 144 (75%) interventions included endoscopic drainage ± necrosectomy. As compared with standard intervention, early intervention was more often performed for infection (91% vs. 39%, p < 0.05), more associated with acute kidney injury (43% vs. 32%, p = 0.09), respiratory failure (41% vs. 22%, p = 0.005), and shock (13% vs. 4%, p < 0.05). Organ failure improved significantly after intervention in both groups. There was a significant difference in mortality (13% vs. 4%, p = 0.02) and need for rescue open necrosectomy (7% vs. 1%, p = 0.03) between groups. Patients undergoing early intervention had increased median hospital (37 days vs. 26 days, p = 0.01) and ICU stay (median 2.5 days vs. 0 days, p = 0.001). There was no difference in complications.

CONCLUSIONS

When using an endoscopically centered step-up strategy in necrotizing pancreatitis, early (<4 weeks) interventions were more often performed for infection and organ failure, with no increase in complications, similar improvement in organ failure, slightly increased need for surgery, and relatively low mortality. Early endoscopic drainage ± necrosectomy should be considered when there is a strong indication for intervention.

Primary and Secondary Organ Failures Cause Mortality Differentially in Acute Pancreatitis and Should be Distinguished

OBJECTIVE

The aim of this study was to study the development of early and late organ failure (OF) and their differential impact on mortality in patients with acute pancreatitis (AP).

METHODS

Consecutive patients (N = 805) with acute pancreatitis were included in an observational study. Organ failure was categorized as primary if it occurred early due to pancreatitis per se and secondary if it occurred late due to infected pancreatic necrosis (IPN). Primary outcome was a relative contribution of primary OF, secondary OF, and IPN to mortality.

RESULTS

Of the 614 patients (mean age, 38.8; standard deviation, 14.6 years; 430 males) in a derivation cohort, 274 (44.6%) developed OF, with 177 having primary OF and 97 secondary OF due to sepsis. Primary OF caused early mortality in 15.8% and was a risk factor for IPN in 76% of patients. Mortality in patients with primary OF and IPN was 49.5% versus 36% in those with IPN and secondary OF (P = 0.06) and 4% in those with IPN but without OF (P < 0.001). The results of the 191 patients in the validation cohort confirmed the relative contribution of primary and secondary OF to mortality.

CONCLUSION

Primary and secondary OF contributed to mortality independently and are distinct in their timing, window of opportunity for intervention, and prognosis.

Analysis of Factors Associated with the Severity of Acute Pancreatitis according to Etiology

Background

The objective of this study was to determine the factors associated with severity of acute pancreatitis (AP) according to two major etiologies: alcohol and gallstones.

Methods

We reviewed the medical records of consecutive patients who were admitted with AP between January 2003 and January 2013. A total of 905 patients with AP (660 alcohol-induced, 245 gallstone-induced) were enrolled. Among them, severe AP (SAP) occurred in 72 patients (53 alcohol-induced, 19 gallstone-induced). Contributing factors between patients with and without SAP were analyzed according to the etiology.

Results

Multivariate analysis demonstrated that current smoking, pancreatic necrosis, and bacteremia were associated with AP severity in both alcohol- and gallstone-induced AP. Pancreatic fluid collection was significantly associated with alcohol-induced SAP (p = 0.04), whereas dyslipidemia was significantly associated with gallstone-induced SAP (p = 0.01). Body mass index was significantly correlated with the Bedside Index of Severity in Acute Pancreatitis score in both alcohol- and gallstone-induced AP (p = 0.03 and 0.01, resp.).

Conclusions

Current smoking, pancreatic necrosis, and bacteremia can aggravate the clinical course of AP. Pancreatic fluid collection and dyslipidemia were associated with AP severity according to the different etiologies. Obesity may also be associated with AP severity in both etiologies.

Update: Role of surgery in acute necrotizing pancreatitis

Acute necrotizing pancreatitis is a prevalent disease with high morbidity and mortality. The development of radiologic and endoscopic techniques to manage pancreatic necrosis commands a multidisciplinary approach, which has considerably decreased the need for laparotomy. The objective of this update is to define the role of surgery in the multidisciplinary approach to management of necrotizing acute pancreatitis.

Natural History After Acute Necrotizing Pancreatitis: a Large US Tertiary Care Experience

BACKGROUND

Most studies of acute necrotizing pancreatitis (ANP) focus on short-term outcomes. We evaluated long-term survival and outcomes following ANP.

METHODS

Patients treated for ANP at the University of Pittsburgh Medical Center from 2001 to 2008 were studied. Data on presentation and course during initial hospitalization and follow-up (median 34 months) was extracted.

RESULTS

Mean age of patients (n = 167) was 53 ± 16 years; 70 % were male, 94 % white, 71 % transfers, 52 % biliary etiology, and 78 % had first-attack of acute pancreatitis. Majority had severe disease with high Acute Physiology and Chronic Health Evaluation II (APACHE-II) score (median 11), length of stay (median 26 days), intensive care unit (ICU) admission (87 %), presence of systemic inflammatory response syndrome (SIRS) (90 %), persistent organ failure (60 %), and infected necrosis (50 %). Intervention was needed in 74 %. Eighteen (10.8 %) patients died during index hospitalization, 9 (5.4 %) during the first year, and 13 (7.8 %) after 1 year. Median survival was significantly shorter when compared with age- and sex-matched US general population (9.1 vs. 26.1 years, p < 0.001). Increasing age (HR 1.05), persistent organ failure (HR 4.5), and >50 % necrosis (HR 3.8) were independent predictors of death at 1 year. In eligible patients, new-onset diabetes, oral pancreatic enzyme replacement therapy, and disability were noted in 45, 25, and 53 %, respectively.

CONCLUSION

ANP significantly impacts long-term survival. A high proportion of patients develop functional derangement and disability following ANP.

Ileus is a predictor of local infection in patients with acute necrotizing pancreatitis

BACKGROUND & OBJECTIVES

Infected pancreatic necrosis (IPN) is associated with increased morbidity and mortality. Gut barrier dysfunction has been shown to increase the risk of bacterial translocation from the gut into the pancreatic bed. The primary aim of the study is to evaluate if ileus, a clinical marker of gut barrier dysfunction, can predict the development of IPN.

METHODS

A retrospective cohort study of patients with necrotizing pancreatitis (NP) was conducted from 2000 to 2014. Ileus was defined as ≥2 of the following criteria: nausea/vomiting; inability to tolerate a diet, absence of flatus, abdominal distension and features of ileus on imaging. Extensive necrosis was defined as >30% nonenhancing pancreatic parenchyma on contrast-enhanced CT. Multivariable cox proportional hazard analysis was used to evaluate known and potential predictors of IPN.

RESULTS

142 patients were identified with NP, 61 with IPN and 81 with sterile necrosis. In comparison to a diagnosis of ileus documented in the medical chart, the ileus criteria had a sensitivity, specificity and positive and negative predictive value of 100%, 93%, 78% and 100%, respectively. On multivariate cox proportional hazard analysis, ileus [HR:2.6; 95%CI:1.4-4.9] and extensive necrosis [HR:2.8; 95%CI:1.3-5.8] were independently associated with the development of IPN while there was no association with bacteremia [HR:1.09; 95%CI:0.6-2.1].

CONCLUSION

Ileus in NP can be accurately defined using surgical criteria. Ileus is independently associated with the future development of IPN. Further studies will be needed to determine if ileus can serve as a clinical marker to direct therapeutic interventions aimed at reducing the incidence of IPN.

Clinical practice guideline: management of acute pancreatitis

ABSTRACT

There has been an increase in the incidence of acute pancreatitis reported worldwide. Despite improvements in access to care, imaging and interventional techniques, acute pancreatitis continues to be associated with significant morbidity and mortality. Despite the availability of clinical practice guidelines for the management of acute pancreatitis, recent studies auditing the clinical management of the condition have shown important areas of noncompliance with evidence-based recommendations. This underscores the importance of creating understandable and implementable recommendations for the diagnosis and management of acute pancreatitis. The purpose of the present guideline is to provide evidence-based recommendations for the management of both mild and severe acute pancreatitis as well as the management of complications of acute pancreatitis and of gall stone-induced pancreatitis.

Lung ultrasonography as a direct measure of evolving respiratory dysfunction and disease severity in patients with acute pancreatitis

BACKGROUND

The value of lung ultrasonography in the diagnosis of respiratory dysfunction and severity stratification in patients with acute pancreatitis (AP) was investigated.

METHODS

Over a 3-month period, 41 patients (median age: 59.1 years; 21 males) presenting with a diagnosis of potential AP were prospectively recruited. Each participant underwent lung ultrasonography and the number of comet tails was linked with contemporaneous clinical data. Group comparisons, areas under the curve (AUC) and respective measures of diagnostic accuracy were investigated.

RESULTS

A greater number of comet tails were evident in patients with respiratory dysfunction (P = 0.021), those with severe disease (P < 0.001) and when contemporaneous and maximum CRP exceeded 100 mg/L (P = 0.048 and P = 0.003 respectively). Receiver-operator characteristic plot area under the curve (AUC) was greater when examining upper lung quadrants, using respiratory dysfunction and AP severity as variables of interest (AUC = 0.783, 95% C.I.: 0.544-0.962, and AUC = 0.996, 95% C.I.: 0.982-1.000, respectively). Examining all lung quadrants except for the lower lateral resulted in greater AUCs for contemporaneous and maximum CRP (AUC = 0.708, 95% C.I.: 0.510-0.883, and AUC = 0.800, 95% C.I.: 0.640-0.929).

DISCUSSION

Ultrasonography of non-dependent lung parenchyma can reliably detect evolving respiratory dysfunction in AP. This simple bedside technique shows promise as an adjunct to severity stratification.

Better Outcomes if Percutaneous Drainage Is Used Early and Proactively in the Course of Necrotizing Pancreatitis

PURPOSE

To compare outcomes after percutaneous catheter drainage (PCD) for acute necrotizing pancreatitis versus those in a randomized controlled trial as a reference standard.

MATERIALS AND METHODS

Between September 2010 and August 2014, CT-guided PCD was the primary treatment for 39 consecutive patients with pancreatic necrosis. The indication for PCD was the clinical finding of uncontrolled pancreatic juice leakage rather than infected necrosis. Subsequent to PCD, the drains were proactively studied with fluoroscopic contrast medium every 3 days to ensure patency and position. Drains were ultimately maneuvered to the site of leakage. These 39 patients were compared with 43 patients from the Pancreatitis, Necrosectomy versus Step-up Approach (PANTER) trial.

RESULTS

The CT severity index was similar between studies (median of 8 in each). Time from onset of acute pancreatitis to PCD was shorter in the present series (median, 23 d vs 30 d). The total number of procedures (PCD and subsequent fluoroscopic drain studies) per patient was greater in the present series (mean, 14 vs 2). More patients in the PANTER trial had organ failure (62% vs 84%), required open or endoscopic necrosectomy (0% vs 60%), and experienced in-hospital mortality (0% vs 19%; P < .05 for all).

CONCLUSIONS

Even though patients in the present series had a similar CT severity index as those in the PANTER trial, the former group showed lower incidences of organ failure, need for necrosectomy, and in-hospital mortality. The use of a proactive PCD protocol early, before the development of severe sepsis, appeared to be effective.

Perfusion CT: can it predict the development of pancreatic necrosis in early stage of severe acute pancreatitis?

PURPOSE

Pancreatic necrosis is an important determinant of patient outcome in severe acute pancreatitis (SAP). This prospective study was conducted to evaluate if perfusion CT (PCT) can predict the development of necrosis at an early stage in SAP.

METHODS

PCT was performed within 72 h of abdominal pain in 57 consecutive admitted patients of acute pancreatitis, out of which four patients were excluded. Thirty-two patients were classified as SAP and 21 as mild acute pancreatitis (MAP) on the basis of APACHE II or SIRS criteria or presence of organ failure. All patients underwent a follow-up CECT at 3 weeks to look for pancreatic necrosis.

RESULTS

Out of 32 patients of SAP, 14 patients showed perfusion defects. The mean blood flow (BF) in these areas was 11.47 ± 5.56 mL/100 mL/min and median blood volume (BV) was 3.92 mL/100 mL (0.5-8.49 mL/100 mL). All these patients developed necrosis on follow-up scan. Two patients who did not show perfusion defects also developed necrosis. Remaining 37 patients (16 SAP and 21 MAP) did not show perfusion defect and did not develop necrosis on follow-up. All regions showing BF less than ≤23.45 mL/100 mL/min and BV ≤8.49 mL/100 mL developed pancreatic necrosis. The values of perfusion parameters may vary with the scanner, mathematical model and protocol used. The sensitivity and specificity of PCT for predicting pancreatic necrosis were 87.5% and 100%, respectively. The cut off values of BF and BV for predicting the development of pancreatic necrosis were 27.29 mL/100 mL/min and 8.96 mL/100 mL, respectively, based on ROC curve. PCT is a reliable tool for early prediction of pancreatic necrosis, which may open new avenues to prevent this ominous complication.

Lung ultrasonography as a direct measure of evolving respiratory dysfunction and disease severity in patients with acute pancreatitis

BACKGROUND

The value of lung ultrasonography in the diagnosis of respiratory dysfunction and severity stratification in patients with acute pancreatitis (AP) was investigated.

METHODS

Over a 3-month period, 41 patients (median age: 59.1 years; 21 males) presenting with a diagnosis of potential AP were prospectively recruited. Each participant underwent lung ultrasonography, and the number of comet tails present on scans was linked with contemporaneous clinical data. Group comparisons, areas under the curve (AUC) and respective measures of diagnostic accuracy were investigated.

RESULTS

A greater number of comet tails were evident in patients with respiratory dysfunction (P = 0.013), those with severe disease (P = 0.001) and when contemporaneous and maximum in-patient C-reactive protein (CRP) exceeded 150 mg/l (P = 0.018 and P = 0.049, respectively). Receiver-operator characteristic plot area under the curve (AUC) was greater when examining upper lung quadrants, using respiratory dysfunction and AP severity as variables of interest (AUC = 0.803, 95% CI: 0.583-1.000, and AUC = 0.996, 95% CI: 0.983-1.000, respectively). Examining all lung quadrants resulted in greater AUCs for contemporaneous and maximum CRP (AUC = 0.764, 95% CI: 0.555-0.972, and AUC = 0.704, 95% CI: 0.510-0.898).

DISCUSSION

Ultrasonography of non-dependent lung parenchyma can reliably detect evolving respiratory dysfunction in AP. This simple bedside technique shows promise as an adjunct to severity stratification.

Clinical significance of presence and extent of extrapancreatic necrosis in acute pancreatitis

BACKGROUND AND AIM

Extrapancreatic necrosis (EPN) alone represents a subgroup of pancreatitis with better outcome than patients with pancreatic parenchymal necrosis (PN). However, data on clinical significance of EPN is limited, and significance of the extent of EPN is not known.

METHODS

Two hundred thirteen patients (136 [63.8%] males; mean age: 39.8 ± 13.2 years) with acute pancreatitis were prospectively enrolled and followed up till recovery or death. Contrast-enhanced computed tomography of each patient was retrospectively evaluated for presence of PN and EPN, pleural effusion and ascites. EPN was termed extensive if it extended to paracolic gutters or pelvis.

RESULTS

Twenty-one (9.9%) patients had interstitial pancreatitis, seven (3.3%) patients had PN alone, 48 (22.5%) patients had EPN alone, and 137 (64.3%) patients had combined PN and EPN. Patients with EPN alone had significantly higher frequency of organ failure than patients with interstitial pancreatitis. Compared with patients with EPN alone, the patients with combined necrosis had significantly higher frequency of pleural effusion (88.2% vs. 75%), ascites (41% vs. 20.8%), and need for intervention (32.6% vs. 14.6%). Patients with extensive EPN (n = 57) had significantly higher frequency of pleural effusion, ascites, and multi-organ failure than those with limited EPN.

CONCLUSION

EPN alone should be considered as a separate category of acute pancreatitis as it has less severe course than PN but has more severe course than interstitial pancreatitis. Patients with extensive EPN in spite of having increased frequency of ascites, pleural effusion, and multi-organ failure had similar outcome as compared to patients with limited EPN.

Comparison of scoring systems in predicting the severity of acute pancreatitis

AIM: To investigate the prognostic usefulness of several existing scoring systems in predicting the severity of acute pancreatitis (AP).

METHODS: We retrospectively analyzed the prospectively collected clinical database from consecutive patients with AP in our institution between January 2011 and December 2012. Ranson, Acute Physiology and Chronic Health Evaluation (APACHE)-II, and bedside index for severity in acute pancreatitis (BISAP) scores, and computed tomography severity index (CTSI) of all patients were calculated. Serum C-reactive protein (CRP) levels were measured at admission (CRPi) and after 24 h (CRP₂₄). Severe AP was defined as persistent organ failure for more than 48 h. The predictive accuracy of each scoring system was measured by the area under the receiver-operating curve (AUC).

RESULTS: Of 161 patients, 21 (13%) were classified as severe AP, and 3 (1.9%) died. Statistically significant cutoff values for prediction of severe AP were Ranson ≥ 3, BISAP ≥ 2, APACHE-II ≥ 8, CTSI ≥ 3, and CRP₂₄≥ 21.4. AUCs for Ranson, BISAP, APACHE-II, CTSI, and CRP₂₄ in predicting severe AP were 0.69 (95%CI: 0.62-0.76), 0.74 (95%CI: 0.66-0.80), 0.78 (95%CI: 0.70-0.84), 0.69 (95%CI: 0.61-0.76), and 0.68 (95%CI: 0.57-0.78), respectively. APACHE-II demonstrated the highest accuracy for prediction of severe AP, however, no statistically significant pairwise differences were observed between APACHE-II and the other scoring systems, including CRP₂₄.

CONCLUSION: Various scoring systems showed similar predictive accuracy for severity of AP. Unique models are needed in order to achieve further improvement of prognostic accuracy.

Acute Pancreatitis: Extrapancreatic Necrosis Volume as Early Predictor of Severity

PURPOSE

To determine the volume of extrapancreatic necrosis that predicts severe acute pancreatitis and to assess the reliability of this threshold in predicting severe acute pancreatitis compared with current scoring systems and C-reactive protein (CRP) levels.

MATERIALS AND METHODS

This institutional review board-approved, HIPAA-compliant retrospective study included patients with acute pancreatitis who were examined with computed tomography (CT) 2-6 days after disease onset. Extrapancreatic necrosis volume, Balthazar score, and CT severity index (CTSI) were calculated. CRP levels 48 hours after the onset of symptoms were reviewed. Outcome parameters included organ failure, infection, need for surgery or percutaneous intervention, duration of hospitalization, and/or death. Receiver operating characteristic (ROC) curves were constructed to determine the optimal threshold for predicting clinical outcomes. Pairwise comparisons of areas under ROC curves (AUCs) from the different grading systems were performed. Interobserver and intraobserver agreement in the grading of extrapancreatic necrosis was assessed by using κ statistics.

RESULTS

In 264 patients, significant relationships were found between extrapancreatic necrosis volume and organ failure, infection, duration of hospitalization, need for intervention, and death (P < .001 for all). The optimal threshold for predicting severe acute pancreatitis was 100 mL. Sensitivity and specificity were 95% (19 of 20) and 83% (142 of 172), respectively, for predicting organ failure (vs 100% [20 of 20] and 46% [79 of 172] for the Balthazar score and 25% [five of 20] and 95% [163 of 172] for the CTSI). The extrapancreatic necrosis AUC was the highest for all systems. Interobserver and intraobserver agreement based on the 100-mL threshold was considered to be excellent.

CONCLUSION

A simple grading system based on an objective criterion such as a threshold of 100 mL of extrapancreatic necrosis provides more reliable information for predicting acute pancreatitis outcomes than do the current scoring systems.

Hypotension in the first week of acute pancreatitis and APACHE II score predict development of infected pancreatic necrosis

BACKGROUND

Hypotension and intestinal mucosal ischemia lead to bacterial translocation from the gut lumen into systemic circulation.

AIM

The purpose of this study was to determine the strength of association between different types of organ failure (OF): hypotension (cardiovascular system failure), renal failure, respiratory failure, CNS failure and coagulopathy in the first week of acute pancreatitis (AP) and the subsequent development of infected pancreatic necrosis (IN).

METHODS

Consecutive patients with AP were evaluated for OF and its severity in the first week of hospital admission. Modified multiple organ failure score (MOFS) was used to identify and grade severity of OF. MOFS of ≥2, lasting for more than 48 h was defined as OF. Occurrence of IN (isolation of bacteria in necrosectomy specimen or image guided fine needle aspiration of pancreatic necrosis) was compared between groups with and without OF.

RESULTS

Of the 81 patients, mean age was 40.1 ± 14.4 years and 55 were males; 60 (74 %) patients had OF and 13 (16 %) patients had IN. Occurrence of IN was not significantly different between patients with OF (18.3 %) and without OF (14.3 %), p = 0.48. However IN occurred in 10 % of patients without and 33.7 % patients with hypotension, p = 0.01. The rest of the organ systems analyzed did not show any significant difference in occurrence of infected necrosis. On multivariate analysis independent predictors of occurrence of IN were hypotension (odds ratio, OR 2.5, p < 0.001) and APACHE II score at 24 h of hospital admission (OR 4.77, p < 0.001).

CONCLUSION

Hypotension in the first week of AP and APACHE II score predict development of IN.

A percutaneous drainage protocol for severe and moderately severe acute pancreatitis

BACKGROUND

According to the revised Atlanta classification, severe and moderately severe acute pancreatitis (AP) includes patients with pancreatic and peripancreatic collections with or without organ failure. These collections suggest the presence of pancreatic juice leakage. The aim of this study was to evaluate the efficacy of a percutaneous catheter drainage (PCD) protocol designed to control leakage and decrease disease severity.

METHODS

Among 663 patients with clinical AP, 122 were classified as moderately severe or severe AP (all had collections). The computed tomography severity index (CTSI) score was calculated. The indication for PCD was based on progressive clinical signs and symptoms. Drain patency, position, and need for additional drainage sites were assessed using CT scans and drain studies initially every 3 days using a proactive protocol. Drain fluid was examined for amylase concentration and microbiological culture. Clinicopathological variables for patients with and without PCD were compared. Since there was no mortality, we used prolonged drainage time to measure the success of PCD. Within the group treated with PCD, variables that resulted in prolonged drainage time were analyzed.

RESULTS

PCD was used in 47/122 (39 %) patients of which 33/47 (70 %) had necrosis. PCD cases had a median CTSI of 8 and were classified as moderately severe AP (57 %) and severe AP (43 %). Inhospital mortality was zero. Surgical necrosectomy was not required for patients with necrosis. Independent risk factors for prolonged drainage time were persistent organ failure >48 h (P = 0.001), CTSI 8-10 (P = 0.038), prolonged duration of amylase-rich fluid in drains (P < 0.001), and polymicrobial culture fluid in drains (P = 0.015).

CONCLUSIONS

A proactive PCD protocol persistently maintaining drain patency advanced to the site of leak controlled the prolonged amylase in drainage fluid resulting in a mortality rate of zero.

Heme oxygenase-1 gene promoter polymorphism is associated with the development of necrotizing acute pancreatitis

OBJECTIVES

Acute pancreatitis is a severe and frequently life-threatening disease, which can lead to pancreatic necrosis, acute lung injury, systemic inflammatory response syndrome, and other complications. In this study, we hypothesized that the expression of heme oxygenase-1 determined by the number of guanidinium thiocyanate (GT) repeats can influence the occurrence of acute pancreatitis.

METHODS

Patients with acute pancreatitis (n = 131) and age- and sex-matched healthy controls (n = 108) were studied. The polymerase chain reaction products were analyzed by ABI 3130 genetic analyzer and the exact size of the polymerase chain reaction products was determined by GeneMapper software. A short allele was defined as containing 27 GT repeats or fewer, whereas a long allele was more than 27 repeats.

RESULTS

The subjects were categorized into 3 groups on the basis of the genotype results: 1 short and 1 long, 2 short, and 2 long alleles (L/L). Patients with necrotizing disease more frequently were carriers of LL genotype compared with those who had edematous acute pancreatitis. Furthermore, logistic regression analysis revealed that the presence of L/L allele type doubles the risk for developing pancreatic necrosis in patients with acute pancreatitis.

CONCLUSIONS

The polymorphism of the GT repeats in the heme oxygenase-1 promoter region may be a risk factor for developing severe and necrotizing acute pancreatitis.

Early organ dysfunction affects long-term survival in acute pancreatitis patients

BACKGROUND

The effect of early organ dysfunction on long-term survival in acute pancreatitis (AP) patients is unknown.

OBJECTIVE

The aim of this study was to ascertain whether early organ dysfunction impacts on long-term survival after an episode of AP.

METHODS

A retrospective analysis was performed using survival data sourced from a prospectively maintained database of patients with AP admitted to the Royal Infirmary of Edinburgh during a 5-year period commencing January 2000. A multiple organ dysfunction syndrome (MODS) score of ≥ 2 during the first week of admission was used to define early organ dysfunction. After accounting for in-hospital deaths, long-term survival probabilities were estimated using the Kaplan-Meier test. The prognostic significance of patient characteristics was assessed by univariate and multivariate analyses using Cox's proportional hazards methods.

RESULTS

A total of 694 patients were studied (median follow-up: 8.8 years). Patients with early organ dysfunction (MODS group) were found to have died prematurely [mean survival: 10.0 years, 95% confidence interval (CI) 9.4-10.6 years] in comparison with the non-MODS group (mean survival: 11.6 years, 95% CI 11.2-11.9 years) (log-rank test, P = 0.001) after the exclusion of in-hospital deaths. Multivariate analysis confirmed MODS as an independent predictor of long-term survival [hazard ratio (HR): 1.528, 95% CI 1.72-2.176; P = 0.019] along with age (HR: 1.062; P < 0.001), alcohol-related aetiology (HR: 2.027; P = 0.001) and idiopathic aetiology (HR: 1.548; P = 0.048).

CONCLUSIONS

Early organ dysfunction in AP is an independent predictor of long-term survival even when in-hospital deaths are accounted for. Negative predictors also include age, and idiopathic and alcohol-related aetiologies.

Serial serum feline pancreatic lipase immunoreactivity concentrations and prognostic variables in 33 cats with pancreatitis

OBJECTIVE

To identify factors significantly associated with prognosis in cats hospitalized because of pancreatitis.

DESIGN

Prospective case series. Animals-33 cats hospitalized for treatment of pancreatitis (diagnosis determined on the basis of clinical signs and serum feline pancreatic lipase immunoreactivity [fPLI] concentration ≥ 5.4 μg/L).

PROCEDURES

Cats were hospitalized (day 1) for 2 to 16 days and observed for 44 days or until they died or were euthanized. Results of physical examination and hematologic and serum biochemical analysis, including measurement of serum fPLI concentration, performed on the day of hospital admission were analyzed to determine whether they were associated with outcome (ie, survival to at least 44 days vs death or euthanasia).

RESULTS

On day 1, mean × SD serum fPLI concentration among the 33 cats was 22.0 × 16.4 μg/L. Mean age of the cats was 12.7 × 3.8 years (range, 4 to 19 years). Eleven of the 33 (33%) cats died or were euthanized before day 44. In univariate analyses, dyspnea, hypothermia, hypokalemia, hyperkalemia, and serum fPLI concentration were significantly associated with an adverse outcome. However, in a multivariate analysis, only severe dyspnea, hyperkalemia (potassium concentration > 5.5 mmol/L), and serum fPLI concentration at the time of hospital admission were found to be significantly associated with an adverse outcome.

CONCLUSIONS AND CLINICAL RELEVANCE

Results suggested that dyspnea, hyperkalemia, and serum fPLI concentration at the time of hospital admission were significant prognostic factors for cats hospitalized because of pancreatitis.

Effects of hydroxyethyl starch and cell-free hemoglobin on microcirculation, tissue oxygenation, and survival in severe acute porcine pancreatitis: results of a randomized experimental trial

OBJECTIVE

Severe acute pancreatitis is a life-threatening disease with a high mortality; so far, no causal treatment is known. The aim of this study was to evaluate the therapeutic potential of hydroxyethyl starch (HES) and cell-free hemoglobin in an experimental model.

METHODS

Thirty-nine pigs were randomly assigned into 3 groups. Severe acute pancreatitis was induced by intraductal injection of glycodeoxycholic acid in combination with intravenous administration of cerulein. All animals were kept in isovolemic conditions by application of Ringer solution, 10% HES, or cell-free hemoglobin. The pancreatic microcirculation was evaluated over 8 hours. Thereafter, the animals were observed for 6 days followed by killing of the animals and histopathologic examination.

RESULTS

The administration of HES and cell-free hemoglobin led to improved microcirculation and tissue oxygenation compared with the Ringer's group. Consequently, the histopathologic damage was reduced (5.5 [3-8.5] vs 9.5 [7.5-11]; P < 0.001). In addition, the mean survival was significantly longer at 121 hours (95% confidence interval, 102-139) versus the Ringer group's 57 hours (95% confidence interval, 32-82; P < 0.001).

CONCLUSIONS

The administration of HES and cell-free hemoglobin can improve microcirculation in severe acute porcine pancreatitis, with consequent reduction in histopathologic damage and mortality. Therefore, this might represent an interesting therapeutic option in the treatment of severe acute pancreatitis.

Risk factors for pancreatic infection in patients with severe acute pancreatitis: an analysis of 163 cases

OBJECTIVE

We aimed to identify the risk factors for predicting pancreatic infection in patients with severe acute pancreatitis (SAP).

METHODS

In all, 163 patients with SAP were included and divided into two groups based on the presence or absence of pancreatic infection. Their demographic and clinical characteristics, laboratory examination results, complications and treatment modalities were collected from their medical records. Variables were initially screened by univariate analysis and those with statistical significance were then filtered by multivariate analysis to determine the independent risk factors for pancreatic infection in SAP.

RESULTS

Patients having SAP with pancreatic infection had a lower partial pressure of arterial carbon dioxide (PaCO2 ), peripheral white blood cell count and alkaline phosphatase levels, together with a higher computed tomography severity index (CTSI) than those without pancreatic infection, while their lactate dehydrogenase (LDH) levels and blood urea nitrogen were much higher. Pancreatic infection was also more common in patients receiving late fluid resuscitation than in those receiving early fluid resuscitation. Multivariate analyses revealed that increased LDH level, high CTSI, delayed fluid resuscitation and hypoxemia were independent risk factors for pancreatic infection in SAP. The sensitivity, specificity, positive and negative predictive values for a model combining the parameters in predicting pancreatic infection were 84%, 97%, 88% and 96%, respectively, with a cut-off value of 0.393, and the area under the receiver operating characteristic curve was 0.923.

CONCLUSION

Increased LDH, high CTSI, delayed fluid resuscitation and hypoxemia are independent risk factors for predicting pancreatic infection in patients with SAP.

Role of N-13 ammonia PET/CT in diagnosing pancreatic necrosis in patients with acute pancreatitis as compared to contrast enhanced CT--results of a pilot study

BACKGROUND

Contrast enhanced computerized tomography (CECT) is used to determine severity of acute pancreatitis based upon the presence and extent of necrosis. However limitations do exist precluding its applicability in renal failure. Positron emission tomography (PET) imaging for cardiac perfusion shows good uptake of N-13 ammonia ((13)NH3) metabolites in pancreas owing to high perfusion.

AIM

To evaluate the role of (13)NH3 PET/CT in acute pancreatitis and compare it with CECT in diagnosing and quantifying pancreatic necrosis.

MATERIAL AND METHODS

Patients presenting within 1 week of acute pancreatitis were studied. Static PET images were acquired after intravenous injection of 370-740 MBq of (13)NH3. (13)NH3 PET/CT was followed by CECT in the absence of renal impairment. Maximum standard-uptake-value (SUVmax) of pancreas (P) and liver (L) were taken and their ratio (P/L) was estimated to determine perfusion. Areas within pancreas with no tracer uptake were considered necrotic. These patients were managed as per institutional protocol. Patients undergoing (13)NH3 PET/CT for coronary artery disease were used as controls.

RESULTS

29 patients (72% males) were studied of whom 6 had elevated serum creatinine. (13)NH3 PET/CT was done in all patients along with 9 controls while CECT was carried out after PET/CT in 23 patients. Median levels of SUVmax (P/L) in the controls, uninvolved pancreas and necrotic areas were 1.0 (0.86-1.03), 0.66 (0.50-0.92) and 0.12 (0.07-0.21) respectively (p < 0.001). Necrosis estimation was similar in 22/23 patients without renal failure while in one patient only (13)NH3 PET/CT picked up necrosis (<30%). 5/6 patients with renal failure had necrosis on (13)NH(3) PET/CT which was confirmed on surgery or subsequent CECT after improvement of renal failure.

CONCLUSION

This pilot study is the first in literature to diagnose necrosis in patients with acute pancreatitis using (13)NH3 PET/CT. With minimal additional radiation burden, it is possible to estimate the absolute tissue perfusion as well. With no adverse renal side effects, this can be an alternative to CECT in patients with renal failure giving similar information. It has good agreement with CECT with a good interobserver acceptability.

Dissecting the effect of moxifloxacin in mice with infected necrosis in taurocholate induced necrotizing pancreatitis

OBJECTIVES

To investigate the limited benefit of antibiotics in ameliorating the outcome of acute necrotizing pancreatitis, we analyzed antibiotic therapy in primarily infected necrotizing pancreatitis in mice with respect to the local pancreatic pathology as well as systemic, pancreatitis induced adverse events.

METHODS

Sterile pancreatic necrosis (SN) was induced by retrograde injection of 4% taurocholate in the common bile duct of Balb/c mice. Primarily infected pancreatic necrosis (IN) was induced by co-injecting 10(8) CFU/ml Escherichia coli. 10 mg/kg of moxifloxacin was administered prior to pancreatitis induction (AN). After 24 h, animals were sacrificed to examine serum as well as organs for signs of SIRS.

RESULTS

Moxifloxacin significantly reduced bacterial count in pancreatic lysates of animals with infected pancreatic necrosis (IN 4.1·10(7) ± 2.4·10(7) vs. AN 4.9·10(4) ± 2.6·10(4) CFU/g; p < 0.001). However, it did not alter pancreatic histology or pulmonary damage (Histology score: IN 23.8 ± 2.7 vs. AN 22.6 ± 1.7). Moxifloxacin reduced systemic immunoactivation (Serum IL-6: IN 330.5 ± 336.6 vs. 38.7 ± 25.5 pg/ml; p < 0.001), hypoglycemia (serum glucose: IN 105.8 ± 12.7 vs. AN 155.7 ± 39.5 mg/dl; p < 0.001), and serum aspartate aminotransferase (IN 606 ± 89.7 vs. AN 255 ± 52.1; p < 0.05). These parameters were significantly increased in animals with necrotizing pancreatitis.

CONCLUSION

In the experimental setting, initial antibiotic therapy with moxifloxacin in acute infected necrotizing pancreatitis in mice does not have a beneficial impact on pancreatic pathology or pulmonary damage. However, other systemic complications induced by infected necrosis in acute pancreatitis are reduced by the administration of moxifloxacin.

Localized and systemic bacterial infections in necrotizing pancreatitis submitted to surgical necrosectomy or percutaneous drainage of necrotic secretions

Background

Infectious complications are observed in 40-70% of all patients with severe acute pancreatitis. Infections are associated with a significant increase in mortality rates.

Methods

We evaluated the prevalence and characteristics of pancreatic and systemic infections in 46 patients with necrotizing pancreatitis submitted to surgical procedures during their hospital stay as well as the impact of such infectious complications on patient clinical outcome. Samples for microbiological cultures were taken at hospital admission from blood and bile and 2 days after invasive procedure from blood, drainage fluid, bile and necrotic tissues.

Results

74% patients with necrotizing pancreatitis had a localized or systemic infection. At admission, 15% of subjects had positive blood cultures whereas 13% had evidence of bacterial growth from bile cultures. Two days after the invasive procedures for removal of necrotic materials and fluids, blood cultures became positive in 30% of patients in spite of antibiotic prophylaxis and bile cultures resulted positive in 22% of cases. Furthermore, bacterial growth from drainage fluids was found in 30% and from homogenized necrotic material in 44% of cases. As refers to bacterial isolates, all patients had a monomicrobial infection. Carbapenems were the drugs with the best sensitivity profile.

Mortality rate was significantly (p < 0.05) higher among patients with infection (17%) than subjects without infection (8%). Within the infected group, those subjects with evidence of systemic infection (positive blood cultures) developed more complications and demonstrated a higher (p < 0.05) mortality rate (28%) than those who had only a localized infection (10%).

Conclusions

Infectious complications significantly increase mortality in patients with necrotizing pancreatitis. In addition, subjects with systemic infections developed more complications and demonstrated a higher mortality rate in comparison with those having a localized infection. In our study, the sensitivity pattern of the isolated microorganisms suggests to consider carbapenems as the best option for empirical treatment in patients with necrotizing pancreatitis who develop a clear-cut evidence of systemic or localized bacterial infection.

The revised Atlanta classification for acute pancreatitis: updates in imaging terminology and guidelines

Imaging of acute pancreatitis requires not only an understanding of the disease subtypes and the myriad of associated complications but also familiarity with the appropriate radiologic nomenclature as defined by the Atlanta symposium in 1992 and, more recently, by the Acute Pancreatitis Classification Working Group in 2008. The accurate description of the radiological findings plays a critical role in the evaluation and management of patients with acute pancreatitis, particularly those with severe disease. There have been increasing efforts to develop uniformity in the use of terminology used to define the radiologic findings in acute pancreatitis, in particular, the terminology for fluid collections, a common area of inconsistency and confusion. Terms such as "acute peripancreatic fluid collections," "acute post- necrotic fluid collections," "pseudocyst," and "walled-off pancreatic necrosis" are now recommended as they describe the evolution of fluid collections in patients with both interstitial and necrotizing pancreatitis and nonspecific terms such as "pancreatic abscess" and "phlegmon" are being abandoned. In this review we illustrate, with case examples, the standardized terminology used in the radiological and clinical description of acute pancreatitis, its severity, and complications with an emphasis on the role of ultrasound, computed tomography and magnetic resonance imaging. Different management options of the associated complications are also discussed. The use of standardized terminology will hopefully improve the communication between radiologists, gastroenterologists, and surgeons to facilitate treatment planning and will lead to enhanced outcomes for patients with acute pancreatitis as well as create uniformity for enrollment into research studies.