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Dive into the research topics where Alexander P. J. Houdijk is active.

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Featured researches published by Alexander P. J. Houdijk.


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.)


The Lancet | 1998

Randomised trial of glutamine-enriched enteral nutrition on infectious morbidity in patients with multiple trauma

Alexander P. J. Houdijk; Emmy R Rijnsburger; Jaap Jansen; R. I. C. Wesdorp; Jeffery K Weiss; Mark Anthony Mccamish; Tom Teerlink; Stephan Gm Meuwissen; Henk J. Th. M. Haarman; Lambertus G. Thijs; Paul A. M. van Leeuwen

BACKGROUND Infections are an important cause of morbidity and mortality in patients with multiple trauma. Studies in both animals and human beings have suggested that glutamine-enriched nutrition decreases the number of infections. METHODS Patients with multiple trauma with an expected survival of more than 48 h, and who had an Injury Severity Score of 20 or more, were randomly allocated glutamine supplemented enteral nutrition or a balanced, isonitrogenous, isocaloric enteral-feeding regimen along with usual care. Each patient was assessed every 8 h for infection, the primary endpoint. Data were analysed both per protocol, which included enteral feeding for at least 5 days, and by intention to treat. FINDINGS 72 patients were enrolled and 60 received enteral feeding (29 glutamine-supplemented) for at least 5 days. Five (17%) of 29 patients in the glutamine-supplemented group had pneumonia compared with 14 (45%) of 31 patients in the control group (p<0.02). Bacteraemia occurred in two (7%) patients in glutamine group and 13 (42%) in the control group (p<0.005). One patient in the glutamine group had sepsis compared with eight (26%) patients in the control group (p<0.02). INTERPRETATION There was a low frequency of pneumonia, sepsis, and bacteraemia in patients with multiple trauma who received glutamine-supplemented enteral nutrition. Larger studies are needed to investigate whether glutamine-supplemented enteral nutrition reduces mortality.


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.


Journal of Nutrition | 2001

Glutamine Alimentation in Catabolic State

P.G. Boelens; Robert J. Nijveldt; Alexander P. J. Houdijk; Sybren Meijer; Paul A. M. van Leeuwen

Glutamine should be reclassified as a conditionally essential amino acid in the catabolic state because the bodys glutamine expenditures exceed synthesis and low glutamine levels in plasma are associated with poor clinical outcome. After severe stress, several amino acids are mobilized from muscle tissue to supply energy and substrate to the host. Glutamine is one of the most important amino acids that provide this function. Glutamine acts as the preferred respiratory fuel for lymphocytes, hepatocytes and intestinal mucosal cells and is metabolized in the gut to citrulline, ammonium and other amino acids. Low concentrations of glutamine in plasma reflect reduced stores in muscle and this reduced availability of glutamine in the catabolic state seems to correlate with increased morbidity and mortality. Adding glutamine to the nutrition of clinical patients, enterally or parenterally, may reduce morbidity. Several excellent clinical trials have been performed to prove efficacy and feasibility of the use of glutamine supplementation in parenteral and enteral nutrition. The increased intake of glutamine has resulted in lower septic morbidity in certain critically ill patient populations. This review will focus on the efficacy and the importance of glutamine supplementation in diverse catabolic states.


Journal of Parenteral and Enteral Nutrition | 2013

Preoperative Nutrition Status and Postoperative Outcome in Elderly General Surgery Patients: A Systematic Review

Mireille F.M. van Stijn; Ines Korkic-Halilovic; Marjan S. M. Bakker; Tjeerd van der Ploeg; Paul A. M. van Leeuwen; Alexander P. J. Houdijk

BACKGROUND Poor nutrition status is considered a risk factor for postoperative complications in the adult population. In elderly patients, who often have a poor nutrition status, this relationship has not been substantiated. Thus, the aim of this systematic review was to assess the merit of preoperative nutrition parameters used to predict postoperative outcome in elderly patients undergoing general surgery. METHODS A systematic literature search of 10 consecutive years, 1998-2008, in PubMed, EMBASE, and Cochrane databases was performed. Search terms used were nutrition status, preoperative assessment, postoperative outcome, and surgery (hip or general), including their synonyms and MeSH terms. Limits used in the search were human studies, published in English, and age (65 years or older). Articles were screened using inclusion and exclusion criteria. All selected articles were checked on methodology and graded. RESULTS Of 463 articles found, 15 were included. They showed profound heterogeneity in the parameters used for preoperative nutrition status and postoperative outcome. The only significant preoperative predictors of postoperative outcome in elderly general surgery patients were serum albumin and ≥ 10% weight loss in the previous 6 months. CONCLUSIONS This systematic review revealed only 2 preoperative parameters to predict postoperative outcome in elderly general surgery patients: weight loss and serum albumin. Both are open to discussion in their use as a preoperative nutrition parameter. Nonetheless, serum albumin seems a reliable preoperative parameter to identify a patient at risk for nutrition deterioration and related complicated postoperative course.


Journal of Parenteral and Enteral Nutrition | 1994

Glutamine-Enriched Enteral Diet Increases Renal Arginine Production

Alexander P. J. Houdijk; Paul A. M. van Leeuwen; Tom Teerlink; Eveline L. Flinkerbusch; Maria A. Boermeester; Hans P. Sauerwein; R. I. C. Wesdorp

BACKGROUND Arginine (Arg) is generated in the kidney by the conversion of circulating citrulline. The most important source for circulating citrulline is the metabolism of glutamine (Gln) by the gut. In this study, we investigated the influence of an enteral diet enriched with Gln on renal Arg synthesis in the rat. METHODS Rats were fed a 12.5% Gln-enriched diet or an isocaloric, isonitrogenous control diet for 14 days. Kidney plasma flow and arterial and renal venous plasma levels of a number of amino acids were measured, and kidney amino acid fluxes were calculated. RESULTS Compared with the control diet, Gln enrichment resulted in significantly higher arterial plasma levels of circulating citrulline (30%, p < .0001) and Arg (31%, p < .0005). The uptake of circulating citrulline and the subsequent production of Arg by the kidneys were significantly higher in the Gln-enriched group (40% and 38%, respectively) and showed an equimolar relationship in both the control (r = .84, p < .0001) and the Gln-enriched group (r = .83, p < .0001). CONCLUSIONS The findings indicate that enteral Gln supplementation caused significantly increased arterial plasma levels of Arg as a result of increased renal Arg production from circulating citrulline. Considering the multiple important biologic properties of Arg, the reported beneficial effects of Gln in catabolic states might be explained in part by increased renal Arg production.


Surgery | 2015

Eight years of experience with Enhanced Recovery After Surgery in patients with colon cancer: Impact of measures to improve adherence.

Nathalie Bakker; Hamit Cakir; Hieronymus J. Doodeman; Alexander P. J. Houdijk

BACKGROUND Perioperative treatment of patients with colorectal cancer according to the Enhanced Recovery After Surgery (ERAS) protocol has proven to reduce complications and duration of stay. However, strict adherence remains a challenge and the benefits may decrease with lower adherence. In this study, we report on 8 years of adherence to the ERAS protocol and its effect on postoperative outcome in patients with colon cancer. METHODS In 2006, the ERAS protocol was introduced for treatment of colon cancer patients in the Medical Center Alkmaar, a large teaching hospital. Patients scheduled for elective colon cancer resection were included in this study. Adherence to ERAS items was monitored and along with clinical data prospectively gathered in a database. In 2011, several measures to improve adherence were implemented. RESULTS In total, 816 patients were included. Mean adherence rate was 73% in 2006 and 2007, 66% in 2008 and 2009, 63% in 2010 and 2011, and 82% in 2012 and 2013. There was a shorter duration of stay in the years with high adherence (5.7 days) compared with the years with low adherence (7.3 days; P < .001). The ERAS items that were the strongest predictors for a shorter duration of stay were no nasogastric tube, early mobilization, early oral nutrition, early removal of epidural, early removal of catheter, and nonopioid oral analgesia. CONCLUSION It is possible to improve adherence to the ERAS protocol and related outcomes with specific measures. Adherence to the ERAS protocol was related inversely to duration of stay. Only postoperative items of the ERAS protocol were predictive for a shorter duration of stay. Keeping adherence optimal remains an ongoing challenge that requires repeated training and dedicated personnel.


British Journal of Nutrition | 2012

Imbalance of arginine and asymmetric dimethylarginine is associated with markers of circulatory failure, organ failure and mortality in shock patients

M. Visser; M. Vermeulen; Milan C. Richir; Tom Teerlink; Alexander P. J. Houdijk; Piet J. Kostense; Willem Wisselink; Bas A.J.M. de Mol; Paul A. M. van Leeuwen; Heleen M. Oudemans-van Straaten

In shock, organ perfusion is of vital importance because organ oxygenation is at risk. NO, the main endothelial-derived vasodilator, is crucial for organ perfusion and coronary patency. The availability of NO might depend on the balance between a substrate (arginine) and an inhibitor (asymmetric dimethylarginine; ADMA) of NO synthase. Therefore, we investigated the relationship of arginine, ADMA and their ratio with circulatory markers, disease severity, organ failure and mortality in shock patients. In forty-four patients with shock (cardiogenic n 17, septic n 27), we prospectively measured plasma arginine and ADMA at intensive care unit admission, Acute Physiology and Chronic Health Evaluation (APACHE) II-(predicted mortality) and Sequential Organ Failure Assessment (SOFA) score, and circulatory markers to investigate their relationship. Arginine concentration was decreased (34·6 (SD 17·9) μmol/l) while ADMA concentration was within the normal range (0·46 (SD 0·18) μmol/l), resulting in a decrease in the arginine:ADMA ratio. The ratio correlated with several circulatory markers (cardiac index, disseminated intravascular coagulation, bicarbonate, lactate and pH), APACHE II and SOFA score, creatine kinase and glucose. The arginine:ADMA ratio showed an association (OR 0·976, 95 % CI 0·963, 0·997, P = 0·025) and a diagnostic accuracy (area under the curve 0·721, 95 % CI 0·560, 0·882, P = 0·016) for hospital mortality, whereas the arginine or ADMA concentration alone or APACHE II-predicted mortality failed to do so. In conclusion, in shock patients, the imbalance of arginine and ADMA is related to circulatory failure, organ failure and disease severity, and predicts mortality. We propose a pathophysiological mechanism in shock: the imbalance of arginine and ADMA contributes to endothelial and cardiac dysfunction resulting in poor organ perfusion and organ failure, thereby increasing the risk of death.


Journal of Neuroinflammation | 2013

Preoperative cerebrospinal fluid cytokine levels and the risk of postoperative delirium in elderly hip fracture patients

Dunja Westhoff; Joost Witlox; Leo Koenderman; Kees J. Kalisvaart; Jos F. M. de Jonghe; Mireille F. M. van Stijn; Alexander P. J. Houdijk; Inge Cm Hoogland; Alasdair M.J. MacLullich; David J. van Westerloo; Diederik van de Beek; Piet Eikelenboom; Willem A. van Gool

BackgroundAging and neurodegenerative disease predispose to delirium and are both associated with increased activity of the innate immune system resulting in an imbalance between pro- and anti-inflammatory mediators in the brain. We examined whether hip fracture patients who develop postoperative delirium have altered levels of inflammatory mediators in cerebrospinal fluid (CSF) prior to surgery.MethodsPatients were 75 years and older and admitted for surgical repair of an acute hip fracture. CSF samples were collected preoperatively. In an exploratory study, we measured 42 cytokines and chemokines by multiplex analysis. We compared CSF levels between patients with and without postoperative delirium and examined the association between CSF cytokine levels and delirium severity. Delirium was diagnosed with the Confusion Assessment Method; severity of delirium was measured with the Delirium Rating Scale Revised-98. Mann–Whitney U tests or Student t-tests were used for between-group comparisons and the Spearman correlation coefficient was used for correlation analyses.ResultsSixty-one patients were included, of whom 23 patients (37.7%) developed postsurgical delirium. Concentrations of Fms-like tyrosine kinase-3 (P=0.021), Interleukin-1 receptor antagonist (P=0.032) and Interleukin-6 (P=0.005) were significantly lower in patients who developed delirium postoperatively.ConclusionsOur findings fit the hypothesis that delirium after surgery results from a dysfunctional neuroinflammatory response: stressing the role of reduced levels of anti-inflammatory mediators in this process.Trial registrationThe Effect of Taurine on Morbidity and Mortality in the Elderly Hip Fracture Patient.Registration number: NCT00497978. Local ethical protocol number: NL16222.094.07.


World Journal of Gastroenterology | 2011

Glutamate reduces experimental intestinal hyperpermeability and facilitates glutamine support of gut integrity

M. Vermeulen; Jeffrey de Jong; Mathijs J Vaessen; Paul A. M. van Leeuwen; Alexander P. J. Houdijk

AIM To assess whether glutamate plays a similar role to glutamine in preserving gut wall integrity. METHODS The effects of glutamine and glutamate on induced hyperpermeability in intestinal cell lines were studied. Paracellular hyperpermeability was induced in Caco2.BBE and HT-29CL.19A cell lines by adding phorbol-12,13-dibutyrate (PDB) apically, after which the effects of glutamine and glutamate on horseradish peroxidase (HRP) diffusion were studied. An inhibitor of glutamate transport (L-trans-pyrrolidine-2,4-dicarboxylic acid: trans-PDC) and an irreversible blocker (acivicin) of the extracellular glutamine to glutamate converting enzyme, γ-glutamyltransferase, were used. RESULTS Apical to basolateral HRP flux increased significantly compared to controls not exposed to PDB (n = 30, P < 0.001). Glutamine application reduced hyperpermeability by 19% and 39% in the respective cell lines. Glutamate application reduced hyperpermeability by 30% and 20%, respectively. Incubation of HT29CL.19A cells with acivicin and subsequent PDB and glutamine addition increased permeability levels. Incubation of Caco2.BBE cells with trans-PDC followed by PDB and glutamate addition also resulted in high permeability levels. CONCLUSION Apical glutamate -similar to glutamine- can decrease induced paracellular hyperpermeability. Extracellular conversion of glutamine to glutamate and subsequent uptake of glutamate could be a pivotal step in the mechanism underlying the protective effect of glutamine.

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Joost Witlox

University of Amsterdam

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M. Vermeulen

VU University Medical Center

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Tom Teerlink

VU University Medical Center

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