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Dive into the research topics where Alexander F. Schaapherder is active.

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Featured researches published by Alexander F. Schaapherder.


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.)


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.


British Journal of Surgery | 2009

Timing and impact of infections in acute pancreatitis

M.G. Besselink; H.C. van Santvoort; Marja A. Boermeester; Vincent B. Nieuwenhuijs; H. van Goor; Cees H. Dejong; Alexander F. Schaapherder; H. G. Gooszen

Although infected necrosis is an established cause of death in acute pancreatitis, the impact of bacteraemia and pneumonia is less certain.


Stem Cells Translational Medicine | 2013

Autologous Bone Marrow-Derived Mesenchymal Stromal Cells for the Treatment of Allograft Rejection After Renal Transplantation: Results of a Phase I Study

Marlies E.J. Reinders; Johan W. de Fijter; Helene Roelofs; Ingeborg M. Bajema; Dorottya K. de Vries; Alexander F. Schaapherder; Frans H.J. Claas; Paula P.M.C. van Miert; Dave L. Roelen; Cees van Kooten; Willem E. Fibbe; Ton J. Rabelink

Despite excellent short‐term results, long‐term survival of transplanted kidneys has not improved accordingly. Although alloimmune responses and calcineurin inhibitor‐related nephrotoxicity have been identified as main drivers of fibrosis, no effective treatment options have emerged. In this perspective, mesenchymal stromal cells (MSCs) are an interesting candidate because of their immunosuppressive and regenerative properties. Of importance, no other clinical studies have investigated their effects in allograft rejection and fibrosis. We performed a safety and feasibility study in kidney allograft recipients to whom two intravenous infusions (1 million cells per kilogram) of autologous bone marrow (BM) MSCs were given, when a protocol renal biopsy at 4 weeks or 6 months showed signs of rejection and/or an increase in interstitial fibrosis/tubular atrophy (IF/TA). Six patients received MSC infusions. Clinical and immune monitoring was performed up to 24 weeks after MSC infusions. MSCs fulfilled the release criteria, infusions were well‐tolerated, and no treatment‐related serious adverse events were reported. In two recipients with allograft rejection, we had a clinical indication to perform surveillance biopsies and are able to report on the potential effects of MSCs in rejection. Although maintenance immunosuppression remained unaltered, there was a resolution of tubulitis without IF/TA in both patients. Additionally, three patients developed an opportunistic viral infection, and five of the six patients displayed a donor‐specific downregulation of the peripheral blood mononuclear cell proliferation assay, not reported in patients without MSC treatment. Autologous BM MSC treatment in transplant recipients with subclinical rejection and IF/TA is clinically feasible and safe, and the findings are suggestive of systemic immunosuppression.


Annals of Surgery | 2012

Timing of Cholecystectomy After Mild Biliary Pancreatitis A Systematic Review

Mark C. van Baal; Marc G. Besselink; Olaf J. Bakker; Hjalmar C. van Santvoort; Alexander F. Schaapherder; Vincent B. Nieuwenhuijs; Hein G. Gooszen; Bert van Ramshorst; Djamila Boerma

Objectives:To determine the risk of recurrent biliary events in the period after mild biliary pancreatitis but before interval cholecystectomy and to determine the safety of cholecystectomy during the index admission. Background:Although current guidelines recommend performing cholecystectomy early after mild biliary pancreatitis, consensus on the definition of early (ie, during index admission or within the first weeks after hospital discharge) is lacking. Methods:We performed a systematic search in PubMed, Embase, and Cochrane for studies published from January 1992 to July 2010. Included were cohort studies of patients with mild biliary pancreatitis reporting on the timing of cholecystectomy, number of readmissions for recurrent biliary events before cholecystectomy, operative complications (eg, bile duct injury, bleeding), and mortality. Study quality and risks of bias were assessed. Results:After screening 2413 studies, 8 cohort studies and 1 randomized trial describing 998 patients were included. Cholecystectomy was performed during index admission in 483 patients (48%) without any reported readmissions. Interval cholecystectomy was performed in 515 patients (52%) after 40 days (median; interquartile range: 19–58 days). Before interval cholecystectomy, 95 patients (18%) were readmitted for recurrent biliary events (0% vs 18%, P < 0.0001). These included recurrent biliary pancreatitis (n = 43, 8%), acute cholecystitis (n = 17), and biliary colics (n = 35). Patients who had an endoscopic retrograde cholangiopancreatography had fewer recurrent biliary events (10% vs 24%, P = 0.001), especially less recurrent biliary pancreatitis (1% vs 9%). There were no differences in operative complications, conversion rate (7%), and mortality (0%) between index and interval cholecystectomy. Because baseline characteristics were only reported in 26% of patients, study populations could not be compared. Conclusions:Interval cholecystectomy after mild biliary pancreatitis is associated with a high risk of readmission for recurrent biliary events, especially recurrent biliary pancreatitis. Cholecystectomy during index admission for mild biliary pancreatitis appears safe, but selection bias could not be excluded.


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.


Clinical Science | 2008

Enhanced expression and activation of pro-inflammatory transcription factors distinguish aneurysmal from atherosclerotic aorta : IL-6-and IL-8-dominated inflammatory responses prevail in the human aneurysm

Jan H.N. Lindeman; Hazem Abdul-Hussien; Alexander F. Schaapherder; J. Hajo van Bockel; Jan H. von der Thüsen; Dave L. Roelen; Robert Kleemann

Inflammation plays a key role in the pathogenesis of an AAA (abdominal aortic aneurysm); however, the nature of the inflammatory factors and cellular response(s) involved in AAA growth is controversial. In the present study, we set out to determine the aortic levels of inflammatory cytokines in relation to downstream inflammatory transcription factors and cellular responses. A comparison of AAA wall samples with atherosclerotic wall samples taken from the same aortic region allowed AAA-specific inflammatory parameters to be identified that distinguish AAAs from ASD (aortic atherosclerotic disease). RT-PCR (real-time PCR), ELISA, Western blotting and immunohistochemistry were combined to assess cytokines and transcription factors at the mRNA and protein level, and their activation status. Compared with ASD, inflammatory parameters associated with Th1-type [T-bet, IL (interleukin)-2, IFN-gamma (interferon-gamma), TNF-alpha (tumour necrosis factor-alpha), IL-1alpha and cytotoxic T-cells] and Th2-type [GATA3, IL-4, IL-10, IL-13 and B-cells] responses were all increased in AAA samples. Evaluation of major downstream inflammatory transcription factors revealed higher baseline levels of C/EBP (CCAAT/enhancer-binding protein) alpha, beta and delta in the AAA samples. Baseline p65 NF-kappaB (nuclear factor kappaB) and c-Jun [AP-1 (activator protein-1)] levels were comparable, but their activated forms were strongly increased in the AAA samples. Downstream target genes of p65 NF-kappaB, c-Jun, IL-6 and IL-8 were hyperexpressed. Molecular and cellular processes associated with IL-6 and IL-8 hyperactivation were enhanced in the AAA samples, i.e. the expression of phospho-STAT-3 (signal transducer and activator of transcription-3) and perforin were elevated, and the content of plasma cells, neutrophils and vasa vasorum was increased. In conclusion, our findings demonstrate that an AAA is a general inflammatory condition which is characterized by enhanced expression and activation of pro-inflammatory transcription factors, accompanied by IL-6 and IL-8 hyperexpression and exaggerated downstream cellular responses, which together clearly distinguish an AAA from ASD.


The Lancet | 2015

Same-admission versus interval cholecystectomy for mild gallstone pancreatitis (PONCHO): a multicentre randomised controlled trial

David da Costa; Stefan A.W. Bouwense; Nicolien J. Schepers; Marc G. Besselink; Hjalmar C. van Santvoort; Sandra van Brunschot; Olaf J. Bakker; Thomas L. Bollen; Cornelis H.C. Dejong; Harry van Goor; Marja A. Boermeester; Marco J. Bruno; Casper H.J. van Eijck; Robin Timmer; Bas L. Weusten; Esther C. J. Consten; Menno A. Brink; B.W. Marcel Spanier; Ernst Jan Spillenaar Bilgen; Vincent B. Nieuwenhuijs; H. Sijbrand Hofker; Camiel Rosman; Annet Voorburg; K. Bosscha; Peter van Duijvendijk; Jos J. G. M. Gerritsen; Joos Heisterkamp; Ignace H. de Hingh; Ben J. Witteman; Philip M Kruyt

BACKGROUND In patients with mild gallstone pancreatitis, cholecystectomy during the same hospital admission might reduce the risk of recurrent gallstone-related complications, compared with the more commonly used strategy of interval cholecystectomy. However, evidence to support same-admission cholecystectomy is poor, and concerns exist about an increased risk of cholecystectomy-related complications with this approach. In this study, we aimed to compare same-admission and interval cholecystectomy, with the hypothesis that same-admission cholecystectomy would reduce the risk of recurrent gallstone-related complications without increasing the difficulty of surgery. METHODS For this multicentre, parallel-group, assessor-masked, randomised controlled superiority trial, inpatients recovering from mild gallstone pancreatitis at 23 hospitals in the Netherlands (with hospital discharge foreseen within 48 h) were assessed for eligibility. Adult patients (aged ≥18 years) were eligible for randomisation if they had a serum C-reactive protein concentration less than 100 mg/L, no need for opioid analgesics, and could tolerate a normal oral diet. Patients with American Society of Anesthesiologists (ASA) class III physical status who were older than 75 years of age, all ASA class IV patients, those with chronic pancreatitis, and those with ongoing alcohol misuse were excluded. A central study coordinator randomly assigned eligible patients (1:1) by computer-based randomisation, with varying block sizes of two and four patients, to cholecystectomy within 3 days of randomisation (same-admission cholecystectomy) or to discharge and cholecystectomy 25-30 days after randomisation (interval cholecystectomy). Randomisation was stratified by centre and by whether or not endoscopic sphincterotomy had been done. Neither investigators nor participants were masked to group assignment. The primary endpoint was a composite of readmission for recurrent gallstone-related complications (pancreatitis, cholangitis, cholecystitis, choledocholithiasis needing endoscopic intervention, or gallstone colic) or mortality within 6 months after randomisation, analysed by intention to treat. The trial was designed to reduce the incidence of the primary endpoint from 8% in the interval group to 1% in the same-admission group. Safety endpoints included bile duct leakage and other complications necessitating re-intervention. This trial is registered with Current Controlled Trials, number ISRCTN72764151, and is complete. FINDINGS Between Dec 22, 2010, and Aug 19, 2013, 266 inpatients from 23 hospitals in the Netherlands were randomly assigned to interval cholecystectomy (n=137) or same-admission cholecystectomy (n=129). One patient from each group was excluded from the final analyses, because of an incorrect diagnosis of pancreatitis in one patient (in the interval group) and discontinued follow-up in the other (in the same-admission group). The primary endpoint occurred in 23 (17%) of 136 patients in the interval group and in six (5%) of 128 patients in the same-admission group (risk ratio 0·28, 95% CI 0·12-0·66; p=0·002). Safety endpoints occurred in four patients: one case of bile duct leakage and one case of postoperative bleeding in each group. All of these were serious adverse events and were judged to be treatment related, but none led to death. INTERPRETATION Compared with interval cholecystectomy, same-admission cholecystectomy reduced the rate of recurrent gallstone-related complications in patients with mild gallstone pancreatitis, with a very low risk of cholecystectomy-related complications. FUNDING Dutch Digestive Disease Foundation.


British Journal of Surgery | 2007

Life-saving therapy for haemorrhaging liver adenomas using selective arterial embolization†

J. H. M. B. Stoot; E. van der Linden; O. T. Terpstra; Alexander F. Schaapherder

Emergency treatment for patients with a ruptured hepatocellular adenoma is controversial. The aim of this study was to evaluate management with selective arterial embolization.

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Vincent B. Nieuwenhuijs

University Medical Center Groningen

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Harry van Goor

University Medical Center Groningen

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Jan H.N. Lindeman

Leiden University Medical Center

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Jan Ringers

Leiden University Medical Center

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Dorottya K. de Vries

Leiden University Medical Center

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