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Featured researches published by Thomas L. Bollen.


Gut | 2013

Classification of acute pancreatitis—2012: revision of the Atlanta classification and definitions by international consensus

Peter A. Banks; Thomas L. Bollen; Christos Dervenis; Hein G. Gooszen; C. D. Johnson; Michael G. Sarr; Gregory G. Tsiotos; Santhi Swaroop Vege

Background and objective The Atlanta classification of acute pancreatitis enabled standardised reporting of research and aided communication between clinicians. Deficiencies identified and improved understanding of the disease make a revision necessary. Methods A web-based consultation was undertaken in 2007 to ensure wide participation of pancreatologists. After an initial meeting, the Working Group sent a draft document to 11 national and international pancreatic associations. This working draft was forwarded to all members. Revisions were made in response to comments, and the web-based consultation was repeated three times. The final consensus was reviewed, and only statements based on published evidence were retained. Results The revised classification of acute pancreatitis identified two phases of the disease: early and late. Severity is classified as mild, moderate or severe. Mild acute pancreatitis, the most common form, has no organ failure, local or systemic complications and usually resolves in the first week. Moderately severe acute pancreatitis is defined by the presence of transient organ failure, local complications or exacerbation of co-morbid disease. Severe acute pancreatitis is defined by persistent organ failure, that is, organ failure >48 h. Local complications are peripancreatic fluid collections, pancreatic and peripancreatic necrosis (sterile or infected), pseudocyst and walled-off necrosis (sterile or infected). We present a standardised template for reporting CT images. Conclusions This international, web-based consensus provides clear definitions to classify acute pancreatitis using easily identified clinical and radiologic criteria. The wide consultation among pancreatologists to reach this consensus should encourage widespread adoption.


The New England Journal of Medicine | 2010

A Step-up Approach or Open Necrosectomy for Necrotizing Pancreatitis

Hjalmar C. van Santvoort; Marc G. Besselink; Olaf J. Bakker; H. Sijbrand Hofker; Marja A. Boermeester; Cornelis H.C. Dejong; Harry van Goor; Alexander F. Schaapherder; Casper H.J. van Eijck; Thomas L. Bollen; Bert van Ramshorst; Vincent B. Nieuwenhuijs; Robin Timmer; Johan S. Laméris; Philip M Kruyt; Eric R. Manusama; Erwin van der Harst; George P. van der Schelling; Tom M. Karsten; Eric J. Hesselink; Cornelis J. H. M. van Laarhoven; Camiel Rosman; K. Bosscha; Ralph J. de Wit; Alexander P. J. Houdijk; Maarten S. van Leeuwen; Erik Buskens; Hein G. Gooszen; Abstr Act

BACKGROUND Necrotizing pancreatitis with infected necrotic tissue is associated with a high rate of complications and death. Standard treatment is open necrosectomy. The outcome may be improved by a minimally invasive step-up approach. METHODS In this multicenter study, we randomly assigned 88 patients with necrotizing pancreatitis and suspected or confirmed infected necrotic tissue to undergo primary open necrosectomy or a step-up approach to treatment. The step-up approach consisted of percutaneous drainage followed, if necessary, by minimally invasive retroperitoneal necrosectomy. The primary end point was a composite of major complications (new-onset multiple-organ failure or multiple systemic complications, perforation of a visceral organ or enterocutaneous fistula, or bleeding) or death. RESULTS The primary end point occurred in 31 of 45 patients (69%) assigned to open necrosectomy and in 17 of 43 patients (40%) assigned to the step-up approach (risk ratio with the step-up approach, 0.57; 95% confidence interval, 0.38 to 0.87; P=0.006). Of the patients assigned to the step-up approach, 35% were treated with percutaneous drainage only. New-onset multiple-organ failure occurred less often in patients assigned to the step-up approach than in those assigned to open necrosectomy (12% vs. 40%, P=0.002). The rate of death did not differ significantly between groups (19% vs. 16%, P=0.70). Patients assigned to the step-up approach had a lower rate of incisional hernias (7% vs. 24%, P=0.03) and new-onset diabetes (16% vs. 38%, P=0.02). CONCLUSIONS A minimally invasive step-up approach, as compared with open necrosectomy, reduced the rate of the composite end point of major complications or death among patients with necrotizing pancreatitis and infected necrotic tissue. (Current Controlled Trials number, ISRCTN13975868.)


JAMA | 2012

Endoscopic Transgastric vs Surgical Necrosectomy for Infected Necrotizing Pancreatitis: A Randomized Trial

Olaf J. Bakker; Hjalmar C. van Santvoort; Sandra van Brunschot; Ronald B. Geskus; Marc G. Besselink; Thomas L. Bollen; Casper H.J. van Eijck; Paul Fockens; Eric J. Hazebroek; Rian M. Nijmeijer; Jan-Werner Poley; Bert van Ramshorst; Frank P. Vleggaar; Marja A. Boermeester; Hein G. Gooszen; Bas L. Weusten; Robin Timmer

CONTEXT Most patients with infected necrotizing pancreatitis require necrosectomy. Surgical necrosectomy induces a proinflammatory response and is associated with a high complication rate. Endoscopic transgastric necrosectomy, a form of natural orifice transluminal endoscopic surgery, may reduce the proinflammatory response and reduce complications. OBJECTIVE To compare the proinflammatory response and clinical outcome of endoscopic transgastric and surgical necrosectomy. DESIGN, SETTING, AND PATIENTS Randomized controlled assessor-blinded clinical trial in 3 academic hospitals and 1 regional teaching hospital in The Netherlands between August 20, 2008, and March 3, 2010. Patients had signs of infected necrotizing pancreatitis and an indication for intervention. INTERVENTIONS Random allocation to endoscopic transgastric or surgical necrosectomy. Endoscopic necrosectomy consisted of transgastric puncture, balloon dilatation, retroperitoneal drainage, and necrosectomy. Surgical necrosectomy consisted of video-assisted retroperitoneal debridement or, if not feasible, laparotomy. MAIN OUTCOME MEASURES The primary end point was the postprocedural proinflammatory response as measured by serum interleukin 6 (IL-6) levels. Secondary clinical end points included a predefined composite end point of major complications (new-onset multiple organ failure, intra-abdominal bleeding, enterocutaneous fistula, or pancreatic fistula) or death. RESULTS We randomized 22 patients, 2 of whom did not undergo necrosectomy following percutaneous catheter drainage and could not be analyzed for the primary end point. Endoscopic transgastric necrosectomy reduced the postprocedural IL-6 levels compared with surgical necrosectomy (P = .004). The composite clinical end point occurred less often after endoscopic necrosectomy (20% vs 80%; risk difference [RD], 0.60; 95% CI, 0.16-0.80; P = .03). Endoscopic necrosectomy did not cause new-onset multiple organ failure (0% vs 50%, RD, 0.50; 95% CI, 0.12-0.76; P = .03) and reduced the number of pancreatic fistulas (10% vs 70%; RD, 0.60; 95% CI, 0.17-0.81; P = .02). CONCLUSION In patients with infected necrotizing pancreatitis, endoscopic necrosectomy reduced the proinflammatory response as well as the composite clinical end point compared with surgical necrosectomy. TRIAL REGISTRATION isrctn.org Identifier: ISRCTN07091918.


Gastroenterology | 2011

A Conservative and Minimally Invasive Approach to Necrotizing Pancreatitis Improves Outcome

Hjalmar C. van Santvoort; Olaf J. Bakker; Thomas L. Bollen; Marc G. Besselink; Usama Ahmed Ali; A. Marjolein Schrijver; Marja A. Boermeester; Harry van Goor; Cornelis H.C. Dejong; Casper H.J. van Eijck; Bert van Ramshorst; Alexander F. Schaapherder; Erwin van der Harst; Sijbrand Hofker; Vincent B. Nieuwenhuijs; Menno A. Brink; Philip M Kruyt; Eric R. Manusama; George P. van der Schelling; Tom M. Karsten; Eric J. Hesselink; Cornelis J. H. M. van Laarhoven; Camiel Rosman; K. Bosscha; Ralph J. de Wit; Alexander P. J. Houdijk; Miguel A. Cuesta; Peter J. Wahab; Hein G. Gooszen

BACKGROUND & AIMS Treatment of patients with necrotizing pancreatitis has become more conservative and less invasive, but there are few data from prospective studies to support the efficacy of this change. We performed a prospective multicenter study of treatment outcomes among patients with necrotizing pancreatitis. METHODS We collected data from 639 consecutive patients with necrotizing pancreatitis, from 2004 to 2008, treated at 21 Dutch hospitals. Data were analyzed for disease severity, interventions (radiologic, endoscopic, surgical), and outcome. RESULTS Overall mortality was 15% (n=93). Organ failure occurred in 240 patients (38%), with 35% mortality. Treatment was conservative in 397 patients (62%), with 7% mortality. An intervention was performed in 242 patients (38%), with 27% mortality; this included early emergency laparotomy in 32 patients (5%), with 78% mortality. Patients with longer times between admission and intervention had lower mortality: 0 to 14 days, 56%; 14 to 29 days, 26%; and >29 days, 15% (P<.001). A total of 208 patients (33%) received interventions for infected necrosis, with 19% mortality. Catheter drainage was most often performed as the first intervention (63% of cases), without additional necrosectomy in 35% of patients. Primary catheter drainage had fewer complications than primary necrosectomy (42% vs 64%, P=.003). Patients with pancreatic parenchymal necrosis (n=324), compared with patients with only peripancreatic necrosis (n=315), had a higher risk of organ failure (50% vs 24%, P<.001) and mortality (20% vs 9%, P<.001). CONCLUSIONS Approximately 62% of patients with necrotizing pancreatitis can be treated without an intervention and with low mortality. In patients with infected necrosis, delayed intervention and catheter drainage as first treatment improves outcome.


Pancreas | 2012

Interventions for Necrotizing Pancreatitis Summary of a Multidisciplinary Consensus Conference

Martin L. Freeman; Jens Werner; Hjalmar C. van Santvoort; Todd H. Baron; Marc G. Besselink; John A. Windsor; Karen D. Horvath; Eric vanSonnenberg; Thomas L. Bollen; Santhi Swaroop Vege

Abstract Pancreatic and peripancreatic necrosis may result in significant morbidity and mortality in patients with acute pancreatitis. Many recommendations have been made for management of necrotizing pancreatitis, but no published guidelines have incorporated the many recent developments in minimally invasive techniques for necrosectomy. Hence, a multidisciplinary conference was convened to develop a consensus on interventions for necrotizing pancreatitis. Participants included most international experts from multiple disciplines. The evidence for efficacy of interventions was reviewed, presentations were given by experts, and a consensus was reached on each topic. In summary, intervention is primarily indicated for infected necrosis, less often for symptomatic sterile necrosis, and should ideally be delayed as long as possible, preferably 4 weeks or longer after the onset of disease, for better demarcation and liquefaction of the necrosis. Both the step-up approach using percutaneous drainage followed by minimally invasive video-assisted retroperitoneal debridement and per-oral endoscopic necrosectomy have been shown to have superior outcomes to traditional open necrosectomy with respect to short-term and long-term morbidity and are emerging as treatments of choice. Applicability of these techniques depends on the availability of specialized expertise and a multidisciplinary team dedicated to the management of severe acute pancreatitis and its complications.


The American Journal of Gastroenterology | 2009

A prospective evaluation of the bedside index for severity in acute pancreatitis score in assessing mortality and intermediate markers of severity in acute pancreatitis.

Vikesh K. Singh; Bechien U. Wu; Thomas L. Bollen; Kathryn Repas; Rie Maurer; Richard S. Johannes; Koenraad J. Mortele; Darwin L. Conwell; Peter A. Banks

OBJECTIVES:Our aim was to prospectively evaluate the ability of the bedside index for severity in acute pancreatitis (BISAP) score to predict mortality as well as intermediate markers of severity in a tertiary center.METHODS:The BISAP score was evaluated among 397 consecutive cases of acute pancreatitis admitted to our institution between June 2005 and December 2007. BISAP scores were calculated on all cases using data within 24 h of presentation. The ability of the BISAP score to predict mortality was evaluated using trend and discrimination analysis. The optimal cutoff score for mortality from the receiver operating curve was used to evaluate the development of organ failure, persistent organ failure, and pancreatic necrosis.RESULTS:Among 397 cases, there were 14 (3.5%) deaths. There was a statistically significant trend for increasing mortality (P < 0.0001) with increasing BISAP score. The area under the receiver operating curve for mortality by BISAP score in the prospective cohort was 0.82 (95% confidence interval: 0.70, 0.95), which was similar to that of the previously published validation cohort. A BISAP score ≥3 was associated with an increased risk of developing organ failure (odds ratio=7.4, 95% confidence interval: 2.8, 19.5), persistent organ failure (odds ratio=12.7, 95% confidence interval: 4.7, 33.9), and pancreatic necrosis (odds ratio=3.8, 95% confidence interval: 1.8, 8.5).CONCLUSIONS:The BISAP score represents a simple way to identify patients at risk of increased mortality and the development of intermediate markers of severity within 24 h of presentation. This risk stratification capability can be utilized to improve clinical care and facilitate enrollment in clinical trials.


The American Journal of Gastroenterology | 2012

A comparative evaluation of radiologic and clinical scoring systems in the early prediction of severity in acute pancreatitis.

Thomas L. Bollen; Vikesh K. Singh; Rie Maurer; Kathryn Repas; Hendrik W. van Es; Peter A. Banks; Koenraad J. Mortele

OBJECTIVES:The early identification of clinically severe acute pancreatitis (AP) is critical for the triage and treatment of patients. The aim of this study was to compare the accuracy of computed tomography (CT) and clinical scoring systems for predicting the severity of AP on admission.METHODS:Demographic, clinical, and laboratory data of all consecutive patients with a primary diagnosis of AP during a two-and-half-year period was prospectively collected for this study. A retrospective analysis of the abdominal CT data was performed. Seven CT scoring systems (CT severity index (CTSI), modified CT severity index (MCTSI), pancreatic size index (PSI), extrapancreatic score (EP), ‘‘extrapancreatic inflammation on CT’’ score (EPIC), ‘‘mesenteric oedema and peritoneal fluid’’ score (MOP), and Balthazar grade) as well as two clinical scoring systems: Acute Physiology, Age, and Chronic Health Evaluation (APACHE)-II and Bedside Index for Severity in AP (BISAP) were comparatively evaluated with regard to their ability to predict the severity of AP on admission (first 24 h of hospitalization). Clinically severe AP was defined as one or more of the following: mortality, persistent organ failure and/or the presence of local pancreatic complications that require intervention. All CT scans were reviewed in consensus by two radiologists, each blinded to patient outcome. The accuracy of each imaging and clinical scoring system for predicting the severity of AP was assessed using receiver operating curve analysis.RESULTS:Of 346 consecutive episodes of AP, there were 159 (46%) episodes in 150 patients (84 men, 66 women; mean age, 54 years; age range, 21–91 years) who were evaluated with a contrast-enhanced CT scan (n=131 episodes) or an unenhanced CT scan (n=28 episodes) on the first day of admission. Clinically severe AP was diagnosed in 29/159 (18%) episodes; 9 (6%) patients died. Overall, the Balthazar grading system (any CT technique) and CTSI (contrast-enhanced CT only) demonstrated the highest accuracy among the CT scoring systems for predicting severity, but this was not statistically significant. There were no statistically significant differences between the predictive accuracies of CT and clinical scoring systems.CONCLUSIONS:The predictive accuracy of CT scoring systems for severity of AP is similar to clinical scoring systems. Hence, a CT on admission solely for severity assessment in AP is not recommended.


Clinical Gastroenterology and Hepatology | 2009

Early systemic inflammatory response syndrome is associated with severe acute pancreatitis.

Vikesh K. Singh; Bechien U. Wu; Thomas L. Bollen; Kathryn Repas; Rie Maurer; Koenraad J. Mortele; Peter A. Banks

BACKGROUND & AIMS There have been few clinical studies of systemic inflammatory response syndrome (SIRS) in patients with acute pancreatitis. The aim of this study was to evaluate the role of SIRS in assessing severity of acute pancreatitis. METHODS We prospectively enrolled 252 consecutive patients with acute pancreatitis who were admitted directly to our institution between 2005-2007. The incidence and duration of SIRS (transient <or=48 hours vs persistent >48 hours) during the first 7 days of hospitalization, and the number of SIRS criteria (0-4) on the first day of hospitalization (day 1) were evaluated with individual markers of severity, including persistent organ failure, pancreatic necrosis, need for intensive care unit, and mortality. RESULTS SIRS occurred in 155/252 patients (62%) on day 1. SIRS on day 1 predicted severe disease with high sensitivity (85%-100%). The absence of SIRS on day 1 was associated with a high negative predictive value (98%-100%). Patients with a higher number of systemic inflammatory response (SIR) criteria on day 1 and persistent SIRS had an increased risk for severe disease (P < .01). CONCLUSIONS The majority of patients hospitalized with acute pancreatitis have SIRS on day 1. The severity of acute pancreatitis is greater among patients with SIRS on day 1 and, in particular, among those with 3 or 4 SIRS criteria, compared with those without SIRS on day 1.


Annals of Surgery | 2009

Intestinal barrier dysfunction in a randomized trial of a specific probiotic composition in acute pancreatitis

Marc G. Besselink; Hjalmar C. van Santvoort; Willem Renooij; Martin De Smet; Marja A. Boermeester; K. Fischer; Harro M. Timmerman; Usama Ahmed Ali; Geert A. Cirkel; Thomas L. Bollen; Bert van Ramshorst; Alexander F. Schaapherder; Ben J. Witteman; Rutger J. Ploeg; Harry van Goor; Cornelis J. H. M. van Laarhoven; Adriaan C. Tan; Menno A. Brink; Erwin van der Harst; Peter J. Wahab; Casper H.J. van Eijck; Cornelis H.C. Dejong; Karel J. van Erpecum; L. M. A. Akkermans; Hein G. Gooszen

Objectives:To determine the relation between intestinal barrier dysfunction, bacterial translocation, and clinical outcome in patients with predicted severe acute pancreatitis and the influence of probiotics on these processes. Summary of Background data:Randomized, placebo-controlled, multicenter trial on probiotic prophylaxis (Ecologic 641) in patients with predicted severe acute pancreatitis (PROPATRIA). Methods:Excretion of intestinal fatty acid binding protein (IFABP, a parameter for enterocyte damage), recovery of polyethylene glycols (PEGs, a parameter for intestinal permeability), and excretion of nitric oxide (NOx, a parameter for bacterial translocation) were assessed in urine of 141 patients collected 24 to 48 h after start of probiotic or placebo treatment and 7 days thereafter. Results:IFABP concentrations in the first 72 hours were higher in patients who developed bacteremia (P = 0.03), infected necrosis (P = 0.01), and organ failure (P = 0.008). PEG recovery was higher in patients who developed bacteremia (PEG 4000, P = 0.001), organ failure (PEG 4000, P < 0.0001), or died (PEG 4000, P = 0.009). Probiotic prophylaxis was associated with an increase in IFABP (median 362 vs. 199 pg/mL; P = 0.02), most evidently in patients with organ failure (P = 0.001), and did not influence intestinal permeability. Overall, probiotics decreased NOx (P = 0.05) but, in patients with organ failure, increased NOx (P = 0.001). Conclusions:Bacteremia, infected necrosis, organ failure, and mortality were all associated with intestinal barrier dysfunction early in the course of acute pancreatitis. Overall, prophylaxis with this specific combination of probiotic strains reduced bacterial translocation, but was associated with increased bacterial translocation and enterocyte damage in patients with organ failure.


Annals of Surgery | 2009

Early endoscopic retrograde cholangiopancreatography in predicted severe acute biliary pancreatitis: A prospective multicenter study

Hjalmar C. van Santvoort; Marc G. Besselink; Annemarie C. de Vries; Marja A. Boermeester; K. Fischer; Thomas L. Bollen; Geert A. Cirkel; Alexander F. Schaapherder; Vincent B. Nieuwenhuijs; Harry van Goor; Cees H. Dejong; Casper H.J. van Eijck; Ben J. Witteman; Bas L. Weusten; Cees J. H. M. van Laarhoven; Peter J. Wahab; Adriaan C. Tan; Matthijs P. Schwartz; Erwin van der Harst; Miguel A. Cuesta; Peter D. Siersema; Hein G. Gooszen; Karel J. van Erpecum

Summary Background Data:The role of early endoscopic retrograde cholangiopancreatography (ERCP) in acute biliary pancreatitis (ABP) remains controversial. Previous studies have included only a relatively small number of patients with predicted severe ABP. We investigated the clinical effects of early ERCP in these patients. Methods:We performed a prospective, observational multicenter study in 8 university medical centers and 7 major teaching hospitals. One hundred fifty-three patients with predicted severe ABP without cholangitis enrolled in a randomized multicenter trial on probiotic prophylaxis in acute pancreatitis were prospectively followed. Conservative treatment or ERCP within 72 hours after symptom onset (at discretion of the treating physician) were compared for complications and mortality. Patients without and with cholestasis (bilirubin: >2.3 mg/dL [40 &mgr;mol/L] and/or dilated common bile duct) were analyzed separately. Results:Of the 153 patients, 81 (53%) underwent ERCP and 72 (47%) conservative treatment. Groups were highly comparable at baseline. Seventy-eight patients (51%) had cholestasis. In patients with cholestasis, ERCP (52/78 patients: 67%), as compared with conservative treatment, was associated with fewer complications (25% vs. 54%, P = 0.020, multivariate adjusted odds ratio [OR]: 0.35, 95% confidence interval [CI]: 0.13–0.99, P= 0.049). This included fewer patients with >30% pancreatic necrosis (8% vs. 31%, P = 0.010). Mortality was nonsignificantly lower after ERCP (6% vs. 15%, P = 0.213, multivariate adjusted OR: 0.44, 95% CI: 0.08–2.28, P = 0.330). In patients without cholestasis, ERCP (29/75 patients: 39%) was not associated with reduced complications (45% vs. 41%, P = 0.814, multivariate adjusted OR: 1.36; 95% CI: 0.49–3.76; P = 0.554) or mortality (14% vs. 17%, P = 0.754, multivariate adjusted OR: 0.78; 95% CI: 0.19–3.12, P = 0.734). Conclusions:Early ERCP is associated with fewer complications in predicted severe ABP if cholestasis is present.

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Hein G. Gooszen

Radboud University Nijmegen

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Harry van Goor

University Medical Center Groningen

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Sandra van Brunschot

Radboud University Nijmegen Medical Centre

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Marco J. Bruno

Erasmus University Rotterdam

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