Impact of characteristics of organ failure and infected necrosis on mortality in necrotising pancreatitis

Using a multidisciplinary team for the staged management and optimally minimally invasive treatment of severe acute pancreatitis

Severe acute pancreatitis (SAP) is a common critical disease with a high mortality rate that involves a complex, rapid change in condition and multiple organ systems. Therefore, a multidisciplinary team (MDT), including staff from the emergency department, intensive care unit, pancreatic surgery, gastroenterology , and imaging, is necessary for the early diagnosis, evaluation, and treatment of patients with SAP. This involves managing the systemic inflammatory response and maintaining organ function in the early stage and managing systemic infection and treatment of peripancreatic complications in the middle-to-late stages. The MDT should be led by departments corresponding to the clinical characteristics of each stage, and those departments should be responsible for the coordination and implementation of treatment by other relevant departments. In the late stage, pancreatic surgery and gastroenterology are the main departments that should manage peripancreatic complications. In line with the principle of minimally invasive treatment, the timely and reasonable selection of endoscopic or minimally invasive surgical debridement can achieve good therapeutic outcomes. Open surgery is also an effective method for treating an intractable massive hemorrhage in the abdominal cavity or necrotic cavity, intractable abdominal compartment syndrome, visceral perforation, and fistulae.

Auxora for the Treatment of Patients With Acute Pancreatitis and Accompanying Systemic Inflammatory Response Syndrome: Clinical Development of a Calcium Release-Activated Calcium Channel Inhibitor

OBJECTIVES

To assess the safety of Auxora in patients with acute pancreatitis (AP), systemic inflammatory response syndrome (SIRS), and hypoxemia, and identify efficacy endpoints to prospectively test in future studies.

METHODS

This phase 2, open-label, dose-response study randomized patients with AP, accompanying SIRS, and hypoxemia (n = 21) to receive low-dose or high-dose Auxora plus standard of care (SOC) or SOC alone. All patients received pancreatic contrast-enhanced computed tomography scans at screenings, day 5/discharge, and as clinically required 90 days postrandomization; scans were blinded and centrally read to determine AP severity using computed tomography severity index. Solid food tolerance was assessed at every meal and SIRS every 12 hours.

RESULTS

The number of patients experiencing serious adverse events was not increased with Auxora versus SOC alone. Three (36.5%) patients with moderate AP receiving low-dose Auxora improved to mild AP; no computed tomography severity index improvements were observed with SOC. By study end, patients receiving Auxora better tolerated solid foods, had less persistent SIRS, and had reduced hospitalization versus SOC.

CONCLUSIONS

The favorable safety profile and patient outcomes suggest Auxora may be an appropriate early treatment for patients with AP and SIRS. Clinical development will continue in a randomized, controlled, blinded, dose-ranging study.

The role of procalcitonin in reducing antibiotics across the surgical pathway

Procalcitonin (PCT) is widely considered as a highly sensitive biomarker of bacterial infection, offering general and emergency surgeons a key tool in the management of surgical infections. A multidisciplinary task force of experts met in Bologna, Italy, on April 4, 2019, to clarify the key issues in the use of PCT across the surgical pathway. The panelists presented the statements developed for each of the main questions regarding the use of PCT across the surgical pathway. An agreement on the statements was reached by the Delphi method, and this document reports the executive summary of the final recommendations approved by the expert panel.

Metabolomic-based clinical studies and murine models for acute pancreatitis disease: A review

Acute pancreatitis (AP) is one of the most common gastroenterological disorders requiring hospitalization and is associated with substantial morbidity and mortality. Metabolomics nowadays not only help us to understand cellular metabolism to a degree that was not previously obtainable, but also to reveal the importance of the metabolites in physiological control, disease onset and development. An in-depth understanding of metabolic phenotyping would be therefore crucial for accurate diagnosis, prognosis and precise treatment of AP. In this review, we summarized and addressed the metabolomics design and workflow in AP studies, as well as the results and analysis of the in-depth of research. Based on the metabolic profiling work in both clinical populations and experimental AP models, we described the metabolites with potential utility as biomarkers and the correlation between the altered metabolites and AP status. Moreover, the disturbed metabolic pathways correlated with biological function were discussed in the end. A practical understanding of current and emerging metabolomic approaches applicable to AP and use of the metabolite information presented will aid in designing robust metabolomics and biological experiments that result in identification of unique biomarkers and mechanisms, and ultimately enhanced clinical decision-making.

Pleural Effusion Is Associated with Severe Renal Dysfunction in Patients with Acute Pancreatitis

BACKGROUND Renal dysfunction is a leading cause of death in patients with acute pancreatitis (AP) and often occurs later than respiratory complications. Whether respiratory complications can predict renal impairment remains unclear. The aim of this study was to investigate the association between pleural effusion and renal dysfunction in AP. MATERIAL AND METHODS Medical records were reviewed from individuals who were hospitalized with AP from January 1, 2015 to December 31, 2019. The patients were divided into 2 groups, based on the presence or absence of pleural effusion on admission. Disease severity, renal function parameters, and outcomes were compared between the 2 groups. RESULTS A total of 222 patients were enrolled, 25 of whom had pleural effusion on admission and 197 who did not. Patients with AP who had pleural effusion had more serious illness (higher incidences of pancreatic inflammation, pancreatic fluid collection, and moderate-to-severe AP; worse Bedside Index for Severity in Acute Pancreatitis score; and a higher modified computed tomography severity index [all P<0.05]) plus worse outcomes (higher incidences of ventilation and vasopressor use [both P<0.05]). Moreover, patients with pleural effusion had a higher level of blood urea nitrogen and lower estimated glomerular filtration rate (both P<0.05). After adjustment for potential confounders, pleural effusion was a risk factor for renal failure in patients with AP (odds ratio 6.32, 95% confidence interval 1.08-36.78, P=0.040). CONCLUSIONS Pleural effusion is associated with severe renal dysfunction in AP. Therefore, efforts should be made to improve early recognition and timely treatment of renal failure by closely monitoring renal function in patients with AP and pleural effusion on admission.

Infectious Complications of Acute Pancreatitis Is Associated with Peripheral Blood Phagocyte Functional Exhaustion

BACKGROUND

Infected pancreatic necrosis is one of the most severe complications of acute pancreatitis (AP). The development of secondary infection doubles the risk of death during the late stage of necrotizing pancreatitis. Phagocytes play a major role in AP pathogenesis, as well as in local and systemic complications of the disease.

AIMS

We aimed to investigate the relationship between quantitative and functional indices of circulating phagocyte at the time of admission and onset of infectious complications in patients with AP afterward.

METHODS

A post hoc analysis of 97 patients with AP was conducted. The metabolic state of peripheral blood neutrophils and monocytes was analyzed based on their phagocytic activity and generation of reactive oxygen species (ROS), which were determined by flow cytometry on admission. The clinical end point was marked by onset of infectious complications of AP.

RESULTS

On admission, baseline values and reactivity reserve of monocyte and neutrophil phagocytic activity in AP patients, who developed septic complications, were substantially decreased, whereas monocyte ROS generation was dramatically increased as compared to the group without infectious processes. ROC curve was obtained both for neutrophil and monocyte phagocytosis reactivity reserve expressed as modulation coefficient values and categorized as the risk factor of infectious complications, showing an area under curve of 0.95 (P < 0.0001) and 0.84 (P < 0.0001), respectively.

CONCLUSIONS

Early (at the time of admission) detection of quantitative and functional indices of circulating phagocytes can be useful for the prediction of septic complications in SAP patients.

Clinical characteristics and management of gastric outlet obstruction in acute pancreatitis

OBJECTIVE

The aim of this study was to describe the clinical characteristics and management of gastric outlet obstruction following acute pancreatitis(AP).

BACKGROUND

Gastric outlet obstruction (GOO) is not uncommon in acute pancreatitis (AP) and can occur throughout the course. However, the clinical features and related treatment of GOO is rarely reported.

METHODS

A retrospective review of AP patients with a diagnosis of GOO from March 2017 to June 2020 was performed. The diagnosis and management of GOO, as well as the demographic characteristics and clinical outcomes of the study patients, were collected and analyzed.

RESULTS

Over the three years, there were 60 AP patients developed GOO, constituting an incidence of 5.7%. Thirty-three patients (55.0%, 33/60) developed GOO in the first 4 weeks and 27 patients (45.0%, 27/60) after 4 weeks from onset. Pancreatic necrosis compression (60.6%; 20/33), gastric outlet gastrointestinal edema (27.3%, 9/33) are the main causes of early-onset GOO (≤4 weeks), while wall-off necrosis (92.6%, 25/27) is the leading cause in the late phase (>4 weeks). The management of GOO incorporates both supportive and specific treatment like gastric decompression, gastric juice reinfusion, percutaneous catheter drainage, etc. The mortality of AP patients with GOO (≤4 weeks) was 21.2% and none patients who developed GOO (>4 weeks) died.

CONCLUSIONS

GOO, as a gastrointestinal complication developed in AP patients, has two peak incidences in the duration of AP and needs to be paid more attention to.

Superoxide Dismutase Predicts Persistent Circulation Failure and Mortality in the Early Stage of Acute Pancreatitis

OBJECTIVES

Oxidative stress is an important event in the pathogenesis of acute pancreatitis. Superoxide dismutase is a major antioxidant enzyme in the body. The aim of this study was to investigate the changes in superoxide dismutase activity early in the onset of acute pancreatitis and its value in predicting the risk of organ failure and mortality.

METHODS

Data for 2549 patients hospitalized from 2013 to 2017 were extracted from the prospective database, and we selected 854 adult patients who were admitted within 24 h of disease onset with complete data. Serum superoxide dismutase activities on the first, second, and third days of hospital admission for patients with different severities, organ failure, and mortality were compared. The areas under the curve for the prediction of organ failure, pancreatic necrosis, and mortality were estimated using receiver operating characteristic curves.

RESULTS

Among the 854 adult patients, superoxide dismutase activities were significantly different among patients with mild acute pancreatitis, moderately severe acute pancreatitis, and severe acute pancreatitis (P = 0.005). Superoxide dismutase activity was significantly decreased in patients with persistent renal failure (77.8 ± 37.2), persistent circulatory failure (66.2 ± 14.9), and mortality (64.3 ± 16.0). The accuracy of superoxide dismutase with regard to predicting persistent circulatory failure and mortality was high, and the areas under the receiver operating characteristic curves were 0.83 and 0.84, respectively.

CONCLUSIONS

Superoxide dismutase activity was negatively correlated with the severity and clinical outcome of AP. Superoxide dismutase activity is highly accurate at predicting persistent circulation failure and mortality in the early stage of AP.

Severe acute pancreatitis: capillary permeability model linking systemic inflammation to multiorgan failure

Severe acute pancreatitis (SAP) includes persistent systemic inflammation (SIRS) and multiorgan failure (MOF). The mechanism of transition from SIRS to MOF is unclear. We developed a fluid compartment model and used clinical data to test predictions. The model includes vascular, interstitial and "third-space" compartments with variable permeability of plasma proteins at the capillaries. Consented patients from University of Pittsburgh Medical Center Presbyterian Hospital were studied. Preadmission and daily hematocrit (HCT), blood urea nitrogen (BUN), creatine (Cr), albumin (Alb), and total protein (TP) were collected, and nonalbumin plasma protein (NAPP = TP minus the Alb) was calculated. Subjects served as their own controls for trajectory analysis. Of 57 SAP subjects, 18 developed MOF (5 died), and 39 were non-MOF (0 died). Compared with preadmission levels, admission HCT increased in MOF +5.00 [25%-75% interquartile range, IQR] versus non-MOF -0.10 [-1.55, 1.40] (P < 0.002) with HCT > +3 distinguishing MOF from non-MOF (odds ratio 17.7, P = 0.014). Preadmission Alb fell faster in MOF than non-MOF (P < 0.01). By day 2, TP and NAPP dropped in MOF but not non-MOF (P < 0.001). BUN and Cr levels increased in MOF (P = 0.001), but BUN-to-Cr ratios remained constant. Pancreatic necrosis was more common in MOF (56%) than non-MOF (23%). Changing capillary permeability to allow loss of NAPP in this model predicts loss of plasma oncotic pressure and reduced vascular volume, hypotension with prerenal azotemia and acute kidney dysfunction, pancreas necrosis, and pulmonary edema from capillary leak in the lung with acute respiratory distress syndrome. Sequential biomarker analysis in humans with or without MOF is consistent with this model. This study is registered on https://clinicaltrials.gov at NCT03075605.NEW & NOTEWORTHY Acute pancreatitis is a sudden inflammatory response to pancreatic injury that may spread to systemic inflammation, multiorgan failure, and death in some patients. With the use of the predictions of a new mechanistic model, we compared patients with severe acute pancreatitis with or without multiorgan failure. All biomarkers of capillary leak and clinical features of multiorgan failure were accurately predicted. This provides a new paradigm for understanding and developing new treatments for patients with severe acute pancreatitis.

Effects of Prophylactic Antibiotics on Length of Stay and Total Costs for Pediatric Acute Pancreatitis: A Nationwide Database Study in Japan

OBJECTIVES

Acute pancreatitis (AP) guidelines for adult patients do not recommend routine prophylactic use of antibiotics because of no clinical merit on mortality, infectious complications, or length of stay. Although the mortality of pediatric AP is low, no studies have explored the rationale for antibiotic use in pediatric patients. The aim of this study was to evaluate the effects of early prophylactic antibiotics on length of stay and total costs in pediatric patients.

METHODS

Using the Japanese Diagnosis Procedure Combination database from 2010 to 2017, we used the stabilized inverse probability of treatment weighting method using propensity scores to balance the background characteristics in the antibiotics group and the control group, and compared length of stay and total costs between the groups.

RESULTS

We found significant differences between the antibiotics group (n = 652) and the control group (n = 467) in length of stay (11 days vs 9 days; percent difference, 15.4%; 95% confidence interval, 5.0%-26.8%) and total costs (US $4085 vs US $3648; percent difference, 19.8%; 95% confidence interval, 8.0%-32.9%).

CONCLUSIONS

Prophylactic antibiotics were associated with longer length of stay and higher total costs. Our results do not support routine use of prophylactic antibiotics in pediatric AP populations.

Assessment of the course of acute pancreatitis in the light of aetiology: a systematic review and meta-analysis

The main causes of acute pancreatitis (AP) are biliary disease, alcohol consumption, hypertriglyceridaemia (HTG) and endoscopic retrograde cholangiopancreatography (ERCP). The aim of this meta-analysis was to evaluate the effects of these aetiological factors on the severity and outcome of AP. Pubmed and Embase were searched between 01/01/2012 and 31/05/2020. Included articles involved adult alcoholic, biliary, HTG- or post-ERCP AP (PAP) patients. Primary outcome was severity, secondary outcomes were organ failures, intensive care unit admission, recurrence rate, pancreatic necrosis, mortality, length of hospital stay, pseudocyst, fluid collection and systematic inflammatory response syndrome. Data were analysed from 127 eligible studies. The risk for non-mild (moderately severe and severe) condition was the highest in HTG-induced AP (HTG-AP) followed by alcoholic AP (AAP), biliary AP (BAP) and PAP. Recurrence rate was significantly lower among BAP vs. HTG-AP or AAP patients (OR = 2.69 and 2.98, 95% CI 1.55–4.65 and 2.22–4.01, respectively). Mortality rate was significantly greater in HTG-AP vs. AAP or BAP (OR = 1.72 and 1.50, 95% CI 1.04–2.84 and 0.96–2.35, respectively), pancreatic necrosis occurred more frequently in AAP than BAP patients (OR = 1.58, 95% CI 1.08–2.30). Overall, there is a potential association between aetiology and the development and course of AP. HTG-AP is associated with the highest number of complications. Furthermore, AAP is likely to be more severe than BAP or PAP. Greater emphasis should be placed on determining aetiology on admission.

Intestinal barrier damage, systemic inflammatory response syndrome, and acute lung injury: A troublesome trio for acute pancreatitis

Severe acute pancreatitis (SAP), a serious inflammatory disease of the pancreas, can easily lead to systemic inflammatory response syndrome (SIRS) and multiple organ dysfunction syndromes (MODS). Acute lung injury (ALI) is one of the most serious complications of SAP. However, the specific pathogenesis of SAP-associated ALI is not fully understood. Crosstalk and multi-mechanisms involving pancreatic necrosis, bacteremia, intestinal barrier failure, activation of inflammatory cascades and diffuse alveolar damage is the main reason for the unclear pathological mechanism of SAP-associated ALI. According to previous research on SAP-associated ALI in our laboratory and theories put forward by other scholars, we propose that the complex pattern of SAP-associated ALI is based on the "pancreas-intestine-inflammation/endotoxin-lung (P-I-I/E-L) pathway". In this review, we mainly concentrated on the specific details of the "P-I-I/E-L pathway" and the potential treatments or preventive measures for SAP-associated ALI.

Impairment of PGC-1 Alpha Up-Regulation Enhances Nitrosative Stress in the Liver during Acute Pancreatitis in Obese Mice

Acute pancreatitis is an inflammatory process of the pancreatic tissue that often leads to distant organ dysfunction. Although liver injury is uncommon in acute pancreatitis, obesity is a risk factor for the development of hepatic complications. The aim of this work was to evaluate the role of PGC-1α in inflammatory response regulation in the liver and its contribution to the detrimental effect of obesity on the liver during acute pancreatitis. For this purpose, we induced acute pancreatitis by cerulein in not only wild-type (WT) and PGC-1α knockout (KO) mice, but also in lean and obese mice. PGC-1α levels were up-regulated in the mice livers with pancreatitis. The increased PGC-1α levels were bound to p65 to restrain its transcriptional activity toward Nos2. Lack of PGC-1α favored the assembly of the p65/phospho-STAT3 complex, which promoted Nos2 expression during acute pancreatitis. The increased transcript Nos2 levels and the pro-oxidant liver status caused by the down-regulated expression of the PGC-1α-dependent antioxidant genes enhanced nitrosative stress and decreased energy charge in the livers of the PGC-1α KO mice with pancreatitis. It is noteworthy that the PGC-1α levels lowered in the obese mice livers, which increased the Nos2 mRNA expression and protein nitration levels and decreased energy charge during pancreatitis. In conclusion, obesity impairs PGC-1α up-regulation in the liver to cause nitrosative stress during acute pancreatitis.

Acute pancreatitis

Acute pancreatitis is an unpredictable and potentially lethal disease. The prognosis mainly depends on the development of organ failure and secondary infection of pancreatic or peripancreatic necrosis. In the past 10 years, treatment of acute pancreatitis has moved towards a multidisciplinary, tailored, and minimally invasive approach. Despite improvements in treatment and critical care, severe acute pancreatitis is still associated with high mortality rates. In this Seminar, we outline the latest evidence on diagnostic and therapeutic strategies for acute pancreatitis.

Early Rapid Fluid Therapy Is Associated with Increased Rate of Noninvasive Positive-Pressure Ventilation in Hemoconcentrated Patients with Severe Acute Pancreatitis

BACKGROUND/AIMS

Hematocrit is a widely used biomarker to guide early fluid therapy for patients with acute pancreatitis (AP), but there is controversy over whether early rapid fluid therapy (ERFT) should be used in hemoconcentrated patients. This study investigated the association of hematocrit and ERFT with clinical outcomes of patients with AP.

METHODS

Data from prospectively maintained AP database and retrospectively collected fluid management details were stratified according to actual severity defined by revised Atlanta classification. Hemoconcentration and "early" were defined as hematocrit > 44% and the first 6 h of general ward admission, respectively, and "rapid" fluid rate was defined as ≥ 3 ml/kg/h. Patients were allocated into 4 groups for comparisons: group A, hematocrit ≤ 44% and fluid rate < 3 ml/kg/h; group B, hematocrit ≤ 44% and fluid rate ≥ 3 ml/kg/h; group C, hematocrit > 44% and fluid rate < 3 ml/kg/h; and group D, hematocrit > 44% and fluid rate ≥ 3 ml/kg/h. Primary outcome was rate of noninvasive positive-pressure ventilation (NPPV).

RESULTS

A total of 912 consecutive AP patients were analyzed. ERFT has no impact on clinical outcomes of hemoconcentrated, non-severe or all non-hemoconcentrated AP patients. In hemoconcentrated patients with severe AP (SAP), ERFT was accompanied with increased risk of NPPV (odds ratio 5.96, 95% CI 1.57-22.6). Multivariate regression analyses confirmed ERFT and hemoconcentration were significantly and independently associated with persistent organ failure and mortality in patients with SAP.

CONCLUSIONS

ERFT is associated with increased rate of NPPV in hemoconcentrated patients with SAP.

Chaiqin chengqi decoction alleviates severity of acute pancreatitis via inhibition of TLR4 and NLRP3 inflammasome: Identification of bioactive ingredients via pharmacological sub-network analysis and experimental validation

BACKGROUND

Chaiqin chengqi decoction (CQCQD) is a Chinese herbal formula derived from dachengqi decoction. CQCQD has been used for the management of acute pancreatitis (AP) in the West China Hospital for more than 30 years. Although CQCQD has a well-established clinical efficacy, little is known about its bioactive ingredients, how they interact with different therapeutic targets and the pathways to produce anti-inflammatory effects.

PURPOSE

Toll-like receptor 4 (TLR4) and the nucleotide-binding oligomerization domain-like receptor family pyrin domain containing 3 (NLRP3) inflammasome-mediated pro-inflammatory signaling pathways, play a central role in AP in determining the extent of pancreatic injury and systemic inflammation. In this study, we screened the bioactive ingredients using a pharmacological sub-network analysis based on the TLR4/NLRP3 signaling pathways followed by experimental validation.

METHODS

The main CQCQD bioactive compounds were identified by UPLC-QTOF/MS. The TLR4/NLRP3 targets in AP for CQCQD active ingredients were confirmed through a pharmacological sub-network analysis. Mice received 7 intraperitoneal injections of cerulein (50 μg/kg; hourly) to induce AP (CER-AP), while oral gavage of CQCQD (5, 10, 15 and 20 g/kg; 3 doses, 2 hourly) was commenced at the 3rd injection of cerulein. Histopathology and biochemical indices were used for assessing AP severity, while polymerase chain reaction, Western blot and immunohistochemistry analyses were used to study the mechanisms. Identified active CQCQD compounds were further validated in freshly isolated mouse pancreatic acinar cells and cultured RAW264.7 macrophages.

RESULTS

The main compounds from CQCQD belonged to flavonoids, iridoids, phenols, lignans, anthraquinones and corresponding glycosides. The sub-network analysis revealed that emodin, rhein, baicalin and chrysin were the compounds most relevant for directly regulating the TLR4/NLRP3-related proteins TLR4, RelA, NF-κB and TNF-α. In vivo, CQCQD attenuated the pancreatic injury and systemic inflammation of CER-AP and was associated with reduced expression of TLR4/NLRP3-related mRNAs and proteins. Emodin, rhein, baicalin and chrysin significantly diminished pancreatic acinar cell necrosis with varied effects on suppressing the expression of TLR4/NLRP3-related mRNAs. Emodin, rhein and chrysin also decreased nitric oxide production in macrophages and their combination had synergistic effects on alleviating cell death as well as expression of TLR4/NLRP3-related proteins.

CONCLUSIONS

CQCQD attenuated the severity of AP at least in part by inhibiting the TLR4/NLRP3 pro-inflammatory pathways. Its active ingredients, emodin, baicalin, rhein and chrysin contributed to these beneficial effects.

Delayed referral increases the need for surgery and intervention in patients with acute pancreatitis

BACKGROUND

The aim was to study the outcomes of acute pancreatitis (AP) patients who were referred from other facilities to a tertiary care centre.

METHODS

Patients with AP were who were referred from other hospitals to a tertiary care centre between April 2013 and September 2019 were studied and their outcomes were analysed. Comparison was made between patients referred early (≤7 days) versus those referred late (>7 days).

RESULTS

Of the 838 patients seen by us, 650 patients (77.6%) were referred from other centres. Median (interquartile range) onset to admission interval was 5 (4-7) days for those who were referred ≤7 days and was 16 (11-30) for those who were referred >7 days. Patients referred beyond 7 days of pain onset had higher rates of development of organ failure (P = 0.007), including acute lung injury (P = 0.008) and acute kidney injury (P = 0.026), infected necrosis (P < 0.0001), requirement of endoscopic/percutaneous drainage (P < 0.001) and need for surgery (P < 0.02) compared to patients who were referred ≤7 days of pain onset. Mortality was however similar in the two groups.

CONCLUSION

Patients with AP referred to a specialized centre with AP early (≤7 days) have better outcomes than those referred late (>7 days) from other facilities.

Gastrointestinal Failure Is a Predictor of Poor Outcome in Patients with Acute Pancreatitis

OBJECTIVE

Although gastrointestinal dysfunction is common in patients with acute pancreatitis, its impact on the outcome of disease has not been adequately studied. The present study was conducted to study the frequency of gastrointestinal failure (GIF) as well as its effect on outcome in patients with acute pancreatitis.

METHODS

Patients with acute pancreatitis admitted in our unit were prospectively studied. Gastrointestinal dysfunction and intra-abdominal pressures were measured daily till their resolution, and gastrointestinal failure score was calculated. Baseline parameters including various severity scores were noted. The patients were followed till clinical recovery or death.

RESULTS

Sixty-four patients (mean age 41.52 ± 16.28 years; 45 (70.3%) males) were prospectively studied. Forty-five (70.3%) patients had severe disease, and 18 (28.1%) patients succumbed to illness. GIF was present in 31 (48.4%) patients. The median duration of GIF was 5 (range 1-20) days. The presence of GIF was significantly associated with mortality (p value < 0.05). On multivariate analysis, the presence of GIF [OR 10.6 (95% CI 1.97-57.04)] and duration of ICU stay [OR 1.08 (95% CI 1.015-1.15)] were found to be independent predictors of mortality.

CONCLUSION

Gastrointestinal failure is an important organ failure in patients with acute pancreatitis and is an independent predictor of mortality. Incorporation of gastrointestinal failure scores in dynamic assessment of patients with acute pancreatitis could help us in better stratifying severity of patients and predicting outcome.

Infectious Complications in Severe Acute Pancreatitis: Pathogens, Drug Resistance, and Status of Nosocomial Infection in a University-Affiliated Teaching Hospital

BACKGROUND

Secondary infection is an important factor affecting mortality and quality of life in patients with severe acute pancreatitis. The characteristics of secondary infection, which are well known to clinicians, need to be re-examined in detail, and their understanding among clinicians needs to be updated accordingly.

AIM

This study aims to investigate the characteristics and drug resistance of pathogens causing severe acute pancreatitis (SAP) secondary infection, to objectively present infection situation, and to provide reference for improved clinical management.

METHODS

A retrospective analysis was performed on 55 consecutive patients with SAP who developed secondary infection with an accurate evidence of bacterial/fungal culture from 2016 to 2018. The statistics included the spectrum and distribution of pathogens, the drug resistance of main pathogens, and associations between multiple infectious parameters and mortality.

RESULTS

A total of 181 strains of pathogens were isolated from (peri)pancreas; bloodstream; and respiratory, urinary, and biliary systems in 55 patients. The strains included 98 g-negative bacteria, 58 g-positive bacteria, and 25 fungi. Bloodstream infection (36.5%) was the most frequent infectious complication, followed by (peri)pancreatic infection (32.0%). Acinetobacter baumannii, Pseudomonas aeruginosa, Klebsiella pneumoniae, Escherichia coli, and Stenotrophomonas maltophilia were predominant among gram-negative bacteria. Gram-positive bacterial infections were mainly caused by Enterococcus faecium and Staphylococcus spp. Fungal infections were predominantly caused by Candida spp. The drug resistance of pathogens causing SAP secondary infection was generally higher than the surveillance level. Patients in the death group were older (55 ± 13 years vs. 46 ± 14 years; p = 0.039) and had longer intensive care unit (ICU) stay (14 vs. 8; p = 0.026) than those in the survival group. A. baumannii infection (68.4% vs. 33%; p = 0.013), number of pathogens ≥ 4 (10 vs. 6; p = 0.005), pancreatic infection (14 vs. 15, p = 0.024), and urinary infection (8 vs. 5; p = 0.019) were significantly associated with mortality.

CONCLUSION

Gram-negative bacteria are the main pathogens causing SAP secondary infection, in which nosocomial infections play a major role. The drug resistance profile of gram-negative bacteria is seriously threatening, and the commonly used antibiotics in SAP are gradually losing their effectiveness. Much attention should be paid to the rational use of antibiotics, and strategies should be established for infection prevention in SAP.

Association between Timing of Surgical Intervention and Mortality in 15,813 Acute Pancreatitis

Objective

In order to find the quantitative relationship between timing of surgical intervention and risk of death in necrotizing pancreatitis.

Methods

The generalized additive model was applied to quantitate the relationship between surgical time (from the onset of acute pancreatitis to first surgical intervention) and risk of death adjusted for demographic characteristics, infection, organ failure, and important lab indicators extracted from the Electronic Medical Record of West China Hospital of Sichuan University.

Results

We analyzed 1,176 inpatients who had pancreatic drainage, pancreatic debridement, or pancreatectomy experience of 15,813 acute pancreatitis retrospectively. It showed that when surgical time was either modelled alone or adjusted for infection or organ failure, an L-shaped relationship between surgical time and risk of death was presented. When surgical time was within 32.60 days, the risk of death was greater than 50%.

Conclusion

There is an L-shaped relationship between timing of surgical intervention and risk of death in necrotizing pancreatitis.

Classification of Infected Necrotizing Pancreatitis for Surgery Within or Beyond 4 Weeks Using Machine Learning

Background: The timing of surgery for necrotizing pancreatitis remains a matter of controversial debate, which has not been resolved by randomized controlled trial (RCT). This study aims to classify surgical timing within or beyond 4 weeks for patients with infected necrotizing pancreatitis by using machine learning methods. Methods: This study analyzed 223 patients who underwent surgery for infected pancreatic necrosis at West China Hospital of Sichuan University. We used logistic regression, support vector machine, and random forest with/without the simulation of generative adversarial networks to classify the surgical intervention within or beyond 4 weeks in the patients with infected necrotizing pancreatitis. Results: Our analyses showed that interleukin 6, infected necrosis, the onset of fever and C-reactive protein were important factors in determining the timing of surgical intervention (< 4 or ≥ 4 weeks) for the patients with infected necrotizing pancreatitis. The main factors associated with postoperative mortality in patients who underwent early surgery (< 4 weeks) included modified Marshall score on admission and preoperational modified Marshall score. Preoperational modified Marshall score, time of surgery, duration of organ failure and onset of renal failure were important predictive factors for the postoperative mortality of patients who underwent delayed surgery (≥ 4 weeks). Conclusions: Machine learning models can be used to predict timing of surgical intervention effectively and key factors associated with surgical timing and postoperative survival are identified for infected necrotizing pancreatitis.

Dexmedetomidine attenuates inflammation and pancreatic injury in a rat model of experimental severe acute pancreatitis via cholinergic anti-inflammatory pathway

BACKGROUND

Excessive inflammatory responses play a critical role in the development of severe acute pancreatitis (SAP), and controlling such inflammation is vital for managing this often fatal disease. Dexmedetomidine has been reported to possess protective properties in inflammatory diseases. Therefore, this study aimed to investigate whether dexmedetomidine pre-treatment exerts an anti-inflammatory effect in rats with SAP induced by sodium taurocholate, and if so, to determine the potential mechanism.

METHODS

SAP was induced with sodium taurocholate. Rats received an intraperitoneal injection of dexmedetomidine 30 min before sodium taurocholate administration. α-bungarotoxin, a selective alpha-7 nicotinic acetylcholine receptor (α7nAchR) antagonist, was injected intra-peritoneally 30 min before dexmedetomidine administration. The role of the vagus nerve was evaluated by performing unilateral cervical vagotomy before the administration of dexmedetomidine. Efferent discharge of the vagal nerve was recorded by the BL-420F Data Acquisition & Analysis System. Six hours after onset, serum pro-inflammatory cytokine (tumor necrosis factor α [TNF-α] and interleukin 6 [IL-6]) levels and amylase levels were determined using an enzyme-linked immunosorbent assay and an automated biochemical analyzer, respectively. Histopathological changes in the pancreas were observed after hematoxylin and eosin staining and scored according to Schmidt criteria.

RESULTS

Pre-treatment with dexmedetomidine significantly decreased serum levels of TNF-α, IL-6, and amylase, strongly alleviating pathological pancreatic injury in the rat model of SAP (TNF-α: 174.2 ± 30.2 vs. 256.1±42.4 pg/ml; IL-6: 293.3 ± 46.8 vs. 421.7 ± 48.3 pg/ml; amylase: 2102.3 ± 165.3 vs. 3186.4 ± 245.2 U/L). However, the anti-inflammatory and pancreatic protective effects were abolished after vagotomy or pre-administration of α-bungarotoxin. Dexmedetomidine also significantly increased the discharge frequency and amplitude of the cervical vagus nerve in the SAP rat model (discharge frequency: 456.8 ± 50.3 vs. 332.4 ± 25.1 Hz; discharge amplitude: 33.4 ± 5.3 vs. 20.5 ± 2.9 μV).

CONCLUSIONS

Dexmedetomidine administration attenuated the systemic inflammatory response and local pancreatic injury caused by SAP in rats through the cholinergic anti-inflammatory pathway involving vagus- and α7nAChR-dependent mechanisms.

Aqueous extraction from dachengqi formula granules reduces the severity of mouse acute pancreatitis via inhibition of pancreatic pro-inflammatory signalling pathways

ETHNOPHARMACOLOGICAL RELEVANCE

Dachengqi decoction (DCQD) belongs to a family of purgative herbal formulas widely used in China for the treatment of acute pancreatitis (AP). AP is a prevalent digestive disease currently without an effective pharmacological intervention. Formula granules have become the preferred method for delivery of herbal formulation in China given its benefit of potency retention, dosing precision and ease of use. The efficacy of DCQD formula granules (DFGs) in experimental AP models has not been investigated.

AIM OF THE STUDY

To analyse and compare the differences in chemical composition of DFGs, with their aqueous extraction (AE) and chloroform extraction (CE) derivatives. To assess their efficacy on severity and targeted pancreatic pro-inflammatory signalling pathways in freshly isolated acinar cells and two models of experimental AP.

MATERIAL AND METHODS

UPLC-Q-TOF-MS was used to analyse chemical components of DFGs and their extractions. Freshly isolated mouse pancreatic acinar cells were treated with taurolithocholic acid 3-sulphate disodium salt (TLCS, 500 μM) with or without DFGs, AE and CE. Apoptotic and necrotic cell death pathway activation was measured by caspase 3/7 (10 μl/mL) and propidium iodide (PI, 1 μM), respectively, using a fluorescent plate reader. Necrotic acinar cells were also counted by epifluorescence microscopy. Mice received either 7 intraperitoneal injections of caerulein (50 μg/kg) at hourly intervals or retrograde infusion of TLCS (3 mM, 50 μl) to induce AP (CER-AP and TLCS-AP, respectively). In CER-AP, mice received oral gavage of DFGs (2.1, 4.2 and 5.2 g/kg), AE (0.6, 1.2, and 2.4 g/kg) and CE (4, 9 and 17 mg/kg), or matched DFGs (1.8 g/kg) and AE (1 g/kg) for 3 times at 2-hourly intervals, or a single intraperitoneal injection of DCQD-related monomers rhein (20 mg/kg), narigeinine (25 mg/kg), and honokiol (5 mg/kg) begun at the 3rd injection of caerulein. In TLCS-AP, DFGs (4.2 g/kg) were given orally at 1, 3 and 5 h post-surgery. Disease severity and pancreatic pro-inflammatory markers were determined.

RESULTS

The main effective anthraquinones and their glycosides, flavonoids and their glycosides, polyphenols and lignans were found in the DFGs. A higher proportion of polar components including glycosides attached to anthraquinones, phenols and flavonoids was found in AE. Conversely, lower polar components containing methoxy substituted flavonoids and anthraquinones were more abundant in CE. DFGs were given at 4.2 g/kg, a consistent reduction in the pancreatic histopathology score and severity indices was observed in both CER-AP and TLCS-AP. In vitro, AE significantly reduced both apoptotic and necrotic cell death pathway activation, while CE increased TLCS-induced acinar cell necrosis. In vivo, AE at dose of 1.2 g/kg consistently reduced pancreatic histopathological scores and myeloperoxidase in the CER-AP that were associated with suppressed expression of pro-inflammatory meditator mRNAs and proteins. CE increased lung myeloperoxidase and failed to protect against CER-AP in all dosages. AE was demonstrated to be more effective than DFGs in reducing pancreatic histopathological scores and myeloperoxidase.

CONCLUSIONS

AE from DFGs alleviated the severity of mouse AP models via an inhibition of pancreatic pro-inflammatory signalling pathways. Efficacy of AE on experimental AP was more potent than its original DFGs and DCQD monomers.

Acute respiratory distress syndrome in acute pancreatitis

Development of organ failure is one of the major determinants of mortality in patients with acute pancreatitis (AP). Acute respiratory distress syndrome (ARDS) is an important cause of respiratory failure in AP and is associated with high mortality. Pathogenesis of ARDS in AP is incompletely understood. Release of various cytokines plays an important role in development of ARDS in AP. Increased gut permeability due to various toxins, inflammatory mediators, and pancreatic enzymes potentiates lung injury by gut-lymph-lung axis leading on to increased translocation of bacterial endotoxins. Various scoring systems, serum levels of various cytokines and lung ultrasound have been evaluated for prediction of development of ARDS in AP with varying results. Various drugs have shown encouraging results in prevention of ARDS in animal models but these encouraging results in animal models are yet to be confirmed in clinical studies. There is no specific effective treatment for ARDS. Treatment of sepsis and local complications of AP should be done according to the standard management strategies. Lung protective ventilatory strategies are of paramount importance to improve outcome of patients of AP with ARDS and therefore effective coordination between gastroenterologists and intensivists is needed for effective management of these patients.

Chaiqin chengqi decoction alleviates severe acute pancreatitis associated acute kidney injury by inhibiting endoplasmic reticulum stress and subsequent apoptosis

BACKGROUND

Acute kidney injury (AKI), characterized by an increase of serum creatinine and urea, is a severe complication of severe acute pancreatitis (SAP) with high mortality. Endoplasmic reticulum (ER) stress has been considered as a key pathologic process in AKI. Chaiqin chengqi decoction (CQCQD) is an effective Chinese medicine formula for SAP treatment in China and has been used for many years. Our goal is to explore the role of CQCQD on ER stress of AKI in experimental SAP.

MATERIALS & METHODS

SAP was induced in rats by retrograde duct injection of 5% sodium taurocholate (NaTC, 1 ml/kg), sham operation (SO) rats simultaneously received saline infusion. Intraperitoneal injection of 4-PBA (50 mg/kg, once a day for three days before the surgery) or intragastric gavage of CQCQD (1 g/kg, 2 hourly × 3 after disease induction) was used to treat SAP rats. All animals were humanely sacrificed 12 h after disease induction. Histopathology scores of kidney and pancreas; serum biochemical indices and kidney protein levels of ER stress and apoptosis markers were assessed. Tubular epithelial cell line (HK-2) was treated either with TNF-α (10 ng/ml) or IL-6 (10 ng/ml) for 12 h plus either 4-PBA (0.1 M) or CQCQD (1 mg/ml) for in vitro study. Cell viability and markers of ER stress and apoptosis were measured.

RESULTS

Ductal perfusion of NaTC caused significant increases in serum lipase, amylase and pancreatic histopathology (inflammatory cell infiltration, interstitial edema, and acinar cell necrosis). Kidney histopathology (tubular dilation, brush border loss, little tubular necrosis, and cast formation), serum creatine and urea levels were raised when compared with the SO group. Moreover, apoptotic cell death markers (caspase-9, cleaved-caspase-3, and TUNEL) and kidney ER stress proteins (BIP, IRE1-α, XBP1s, and CHOP) were elevated after NaTC administration. 4-PBA and CQCQD significantly alleviated histopathological changes of kidney and pancreas, inflammatory cytokines, biochemical markers of AKI, ER stress proteins and apoptotic cell death markers. They also protected HK-2 cells from injury of TNF-α and IL-6, and alleviated both ER stress and apoptosis proteins in vitro.

CONCLUSION

CQCQD may alleviate SAP-related AKI by inhibiting ER stress-related apoptosis.

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.

Comparison of endoscopic versus percutaneous drainage of symptomatic pancreatic necrosis in the early (< 4 weeks) phase of illness

Background and Objective

Pancreatic fluid collections in early phase of illness <4 weeks after onset of acute pancreatitis (AP) are usually treated with percutaneous drainage (PCD). There is a paucity of data comparing early (<4 weeks) endoscopic transluminal drainage (ETD) with PCD in patients with symptomatic pancreatic necrosis (PN). The objective of this study is to compare the safety and efficacy of early ETD with PCD in patients with symptomatic PN.

Patients and Methods

Retrospective analysis of database of patients with symptomatic PN treated early (<4 weeks of onset of AP) with either ETD (encapsulated wall on EUS) or PCD.

Results

Twenty-three patients (19 M; mean age: 36.1 years) were treated with ETD and 41 patients (29 M; mean age: 39.6 years) were treated with PCD, respectively. ETD and PCD were done 24.2 ± 2.3 and 24.2 ± 2.0 days after onset of AP, respectively (P = 0.84). In the ETD group, 35% of patients were treated with self-expanding metallic stents and 48% of patients required direct endoscopic necrosectomy. In the PCD group, 74% of patients were treated with multiple catheters and 91% of patients with either saline or streptokinase irrigation. As compared to the ETD group, patients in the PCD group took longer time for resolution (61.9 ± 22.9 days vs. 30.9 ± 5.6 days; P < 0.00001), increased need for surgery (30% vs. 4%; P = 0.01), and frequency of formation of external pancreatic fistula (EPF) (22% vs. nil; P = 0.02).

Conclusions

ETD of PN in early phase of illness is associated with a shorter duration for resolution and infrequent need of salvage surgery compared to PCD. EPF formation is a significant adverse event with PCD.

Bone marrow-derived mesenchymal stem cells alleviate severe acute pancreatitis-induced multiple-organ injury in rats via suppression of autophagy

Patients with severe acute pancreatitis (SAP) represent a substantial challenge to medical practitioners due to the high associated rates of morbidity and mortality and a lack of satisfactory therapeutic outcomes. In a previous study, our group demonstrated that bone marrow-derived mesenchymal stem cells (BMSCs) can ameliorate SAP; however, the mechanisms of action remain to be fully understood. BMSCs were intravenously injected into SAP rats 12 h after experimental induction of SAP using sodium taurocholate (NaT). Histopathological changes and the levels of pro-inflammatory mediators were assessed by hematoxylin and eosin (H&E) staining and ELISA, respectively. Autophagy levels were assessed using qRT-PCR, western blotting, immunohistochemistry, immunofluorescence, and transmission electron microscopy. AR42J cells and human umbilical vein endothelial cells (HUVECs) were administered BMSC-conditioned media (BMSC-CM) after NaT treatment, and cell viability was measured using a Cell Counting Kit-8 (CCK-8) and flow cytometry. In vivo, BMSCs effectively reduced multiple systematic inflammatory responses, suppressed the activation of autophagy, and improved intestinal dysfunction. In vitro, BMSC-CM significantly improved the viability of injured cells, promoted angiogenesis, and decreased autophagy. We therefore propose that the administration of BMSCs alleviates SAP-induced multiple organ injury by inhibiting autophagy.

Adverse clinical outcomes associated with multidrug-resistant organisms in patients with infected pancreatic necrosis

BACKGROUND

Multidrug-resistant organisms (MDROs) is becoming a serious worldwide threat to public health. However, the impact of MDROs on the outcomes of the patients with infected pancreatic necrosis (IPN) remains unclear. This study aims to evaluate the roles of MDROs in IPN.

METHODS

A prospectively maintained database of 188 patients with IPN between January 2010 and May 2019 was analyzed. The microbiology profile of organisms isolated from wall-off necrosis (WON) was specifically investigated to correlate with the outcomes of the patients.

RESULTS

Of the 188 patients with IPN, 108 patients (57.4%) had MDROs detected in aspirates from WON. Carbapenem-resistant Klebsiella pneumoniae (CRKP) accounted for 43.5% of the MDROs isolated (60/138), followed by Carbapenem-resistant Acinetobacter baumanii (CRAB) (34.8%, 48/138) and Escherichia coli producing an extended-spectrum beta-lactamase (ESBLp) (6.5%, 9/138). MDROs infection was associated with higher mortality (35.2% vs 11.3%, P < 0.001), higher rate of hemorrhage (36.1% vs 11.3%, P < 0.001), longer intensive care unit (ICU) stay (23 vs 12 days, P < 0.001), longer hospital stay (68 vs 51 days, P = 0.001) and more hospitalization expenses (45,190 ± 31,680 vs 26,965 ± 17,167 $, P < 0.001). Multivariate analysis of predictors of mortality indicated that MDROs infection (OR = 2.6; 95% confidence interval [CI], 1.0-6.5; P = 0.042), age ≥ 50 years (OR = 2.6; 95% CI, 1.2-5.8; P = 0.016), severe category (OR = 2.9; 95% CI, 1.1-8.0; P = 0.035), bloodstream infection (OR = 3.4; 95% CI, 1.5-7.6; P = 0.049), step-down surgical approach (OR = 2.7; 95% CI, 1.1-6.2; P = 0.023) were significant factors.

CONCLUSIONS

MDROs infection was prevalent among patients with IPN and associated with adverse clinical outcomes and increased mortality.

The efficacy of low molecular weight heparin in severe acute pancreatitis: A systematic review and meta-analysis of randomized controlled trials

OBJECTIVE

The effects of low molecular weight heparin (LMWH) on severe acute pancreatitis (SAP) have been controversial. We aimed to evaluate the efficacy of LMWH on prognosis of SAP by systematic review and meta-analysis.

METHODS

We searched relevant studies published up to March 2019 in five databases (MEDLINE/PubMed, EMBASE, the Cochrane Central Register of Controlled Trials in Cochrane Library, China National Knowledge Infrastructure, and the Chinese Journal of Science and Technology of VIP database).

RESULTS

Sixteen randomized controlled trials with 1625 patients were included in the final analysis. Most studies were from China. In analysis of laboratory parameters and clinical scores, SAP patients receiving LMWH treatment had lower white blood cell counts, C-reactive protein level, Acute Physiology and Chronic Health Evaluation II score, and computed tomography severity index. In clinical outcomes, SAP patients who received LMWH treatment had shorter hospital stay (pooled mean difference [95% confidence interval; CI] -8.79 [-11.18, -6.40], P < .01), lower mortality (pooled risk ratio [RR] [95% CI] 0.33 [0.24-0.44], P < .01), lower incidences of multiple organ failure (pooled RR [95% CI] 0.34 [0.23-0.52], P < .01), pancreatic pseudocyst (pooled RR [95% CI] 0.49 [0.27-0.90], P = .02), and operation rate (pooled RR [95% CI] 0.39 [0.31-0.50], P < .01).

CONCLUSIONS

LMWH could improve the prognosis of SAP, and has a potential role in reducing hospital stay, mortality, incidences of multiple organ failure, pancreatic pseudocyst, and operation rate.

Pharmacologic management and prevention of acute pancreatitis

PURPOSE OF REVIEW

The present article will focus in pharmacologic agents that have been studied to improve acute pancreatitis outcomes, and to prevent the disease at different levels.

RECENT FINDINGS

Too little and too much early fluid resuscitation can be harmful. The optimal volume, rate, and duration of intravenous fluid therapy is still unknown. Nonopioid analgesics should be the first line of analgesia in patients with acute pancreatitis. A few pharmacologic agents evaluated in acute pancreatitis have resulted in positive pilot trials; however, larger randomized clinical trials (RCTs) are needed before final conclusions. Statin use is associated with lower incidence of acute pancreatitis in the general population and ongoing studies are evaluating its preventive role in acute pancreatitis recurrences. The preventive role of rectal indomethacin in post-endoscopic retrograde cholangiopancreatography pancreatitis is indisputable, with subject selection and timing of administration requiring further investigation.

SUMMARY

There is still no proven effective disease-specific pharmacologic therapy that changes the natural history of acute pancreatitis. New therapeutic targets and pharmacologic agents are in the horizon. Careful refinement in study design is needed when planning future RCTs. There is also a need for drug development aiming at reducing the incidence of the disease and preventing its sequelae.

New insights into acute pancreatitis

The incidence of acute pancreatitis continues to increase worldwide, and it is one of the most common gastrointestinal causes for hospital admission in the USA. In the past decade, substantial advancements have been made in our understanding of the pathophysiological mechanisms of acute pancreatitis. Studies have elucidated mechanisms of calcium-mediated acinar cell injury and death and the importance of store-operated calcium entry channels and mitochondrial permeability transition pores. The cytoprotective role of the unfolded protein response and autophagy in preventing sustained endoplasmic reticulum stress, apoptosis and necrosis has also been characterized, as has the central role of unsaturated fatty acids in causing pancreatic organ failure. Characterization of these pathways has led to the identification of potential molecular targets for future therapeutic trials. At the patient level, two classification systems have been developed to classify the severity of acute pancreatitis into prognostically meaningful groups, and several landmark clinical trials have informed management strategies in areas of nutritional support and interventions for infected pancreatic necrosis that have resulted in important changes to acute pancreatitis management paradigms. In this Review, we provide a summary of recent advances in acute pancreatitis with a special emphasis on pathophysiological mechanisms and clinical management of the disorder.

Management of infected pancreatic necrosis in the intensive care unit: a narrative review

BACKGROUND

Severe acute pancreatitis is marked by organ failure and (peri)pancreatic necrosis with local complications such as infected necrosis. Infection of these necrotic collections together with organ failure remain the major causes of admission to an intensive care unit (ICU) in acute pancreatitis. Appropriate treatment of infected necrosis is essential to reduce morbidity and mortality. Overall knowledge of the treatment options within a multidisciplinary team-with special attention to the appropriate use of antimicrobial therapy and invasive treatment techniques for source control-is essential in the treatment of this complex disease.

OBJECTIVES

To address the current state of microbiological diagnosis, antimicrobial treatment, and source control for infected pancreatic necrosis in the ICU.

SOURCES

A literature search was performed using the Medline and Cochrane libraries for articles subsequent to 2003 using the keywords: infected necrosis, pancreatitis, intensive care medicine, treatment, diagnosis and antibiotic(s).

CONTENT

This narrative review provides an overview of key elements of diagnosis and treatment of infected pancreatic necrosis in the ICU.

IMPLICATIONS

In pancreatic necrosis it is essential to continuously (re)evaluate the indication for antimicrobial treatment and invasive source control. Invasive diagnostics (e.g. through fine-needle aspiration, FNA), preferably prior to the start of broad-spectrum antimicrobial therapy, is advocated. Antimicrobial stewardship principles apply: paying attention to altered pharmacokinetics in the critically ill, de-escalation of broad-spectrum therapy once cultures become available, and early withdrawal of antibiotics once source control has been established. This is important to prevent the development of antimicrobial resistance, especially in a group of patients who may require repeated courses of antibiotics during the prolonged course of their illness.

Outcomes of infected pancreatic necrosis complicated with duodenal fistula in the era of minimally invasive techniques

Background: Duodenal fistula (DF) was reportedly thought to be the second most common type of gastrointestinal fistula secondary to acute necrotizing pancreatitis. However, infected pancreatic necrosis (IPN) associated DF (IPN-DF) was rarely specifically reported in the literature. The outcome of IPN-DF was also less well recognized, especially in the era of minimally invasive techniques. A retrospective cohort study was designed mainly focused on the management and outcomes of IPN-DF in the era of minimally invasive techniques. Methods: One hundred and twenty-one consecutive patients diagnosed with IPN between January 2015 and May 2018 were enrolled retrospectively. Among them, 10 patients developed DF. The step-up minimal invasive techniques were highlighted and outcomes were analyzed. Results: Compared with patients without IPN-DF, patients with IPN-DF had longer hospital stay (95.8 vs. 63.5 days, p < .01), but similar mortality rates (10% vs. 21.6%, p > .05). The median interval between the onset of acute pancreatitis (AP) and detection of DF was 2.4 months (1-4 months). The median duration of DF was 1.5 months (0.5-3 months). Out of the 10 patients with DF, 9 had their fistulas resolve spontaneously over time by means of controlling the source of infection with the use of minimally invasive techniques and providing enteral nutritional support, while one patient died of uncontrolled sepsis. No open surgery was performed. On follow-up, the 9 patients recovered completely and remained free of infection and leakage. Conclusion: IPN-DF could be managed successfully using minimally invasive techniques in specialized acute pancreatitis (AP) center. Patients with IPN-DF suffered from a longer hospital stay, but similar mortality rate compared with patients without DF.

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.

Risk Stratification and Early Conservative Treatment of Acute Pancreatitis

BACKGROUND

Acute pancreatitis (AP) is a potentially life-threatening common gastrointestinal disorder with increasing incidence around the globe. Although the majority of cases will take an uneventful, mild course, a fraction of patients is at risk of moderately severe or severe pancreatitis which is burdened with substantial morbidity and mortality. Early identification of patients at risk of a severe disease course and an adopted treatment strategy are crucial to avoid adverse outcomes.

SUMMARY

In this review we summarize the most recent concepts of severity grading in patients diagnosed with AP by adopting recommendations of current guidelines and discussing them in the context of the available literature. The severity of AP depends on the presence of local and/or systemic complications and organ failure. To predict the severity early in the disease course, host-specific factors (age, comorbidities, body mass index), clinical risk factors (biochemical and physiological parameters and scoring systems), as well as the response to initial therapy need to be considered and revisited in the short term. Depending on the individual risk and comorbidity the initial treatment can be guided, which will be discussed in the second part of this review.

KEY MESSAGE

Predicting the severity of AP and adapting the individual treatment strategy requires multidimensional risk assessment and close observation during the early phase of AP development.

Increased Mortality from Extrapancreatic Infections in Hospitalized Patients with Acute Pancreatitis

Nosocomial extrapancreatic infections in patients with acute pancreatitis (AP) are associated with a higher mortality even after adjusting the risk for the severity of the pancreatitis. The aim of this study was to describe the clinical features of hospitalized patients with AP who died during their hospitalization and to evaluate risk factors associated with mortality. We performed a descriptive study of the clinical features of adult patients who died from AP during their hospitalization and a case control study with a paired group of patients that survived AP during a 10-year period. Data of interest were collected from the medical records and are presented with appropriate measures of central tendency and dispersion. For the case control study, the primary outcome evaluated was death, and to evaluate associated clinical features and determine differences between groups, we performed the χ² or Fisher's exact tests for categorical variables and the Student t-test or Mann-Whitney U test for continuous variables as appropriate. We found 48 patients with acute pancreatitis who died within the period of the study during hospitalization; from these, 50% were men, mean age was 53.2 years, and the most common etiology was biliary obstruction by gallstones in 45.8%. The global mortality rate was of 2.5%. A total of 43.7% patients had infected pancreatic necrosis, and in 58.3%, some extrapancreatic infection was documented, being the most common urinary tract infection in 50%, bacteremia in 50% and pneumonia in 33.3%. Clinical features associated with mortality were the presence of organ failure (p < 0.001), nosocomial complications (p < 0.001), infected necrosis (p < 0.001), and extrapancreatic infections (p = 0.002). From the different extrapancreatic infections, only bacteremia (p = 0.001) and pneumonia (p = 0.011) were associated with higher mortality. In conclusion, extrapancreatic infections are associated with increased mortality among hospitalized patients with acute pancreatitis, in particular, bacteremia and pneumonia with an isolated pathogen.