J C Kalff

University of Bonn, Bonn, North Rhine-Westphalia, Germany

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Publications (99)235.67 Total impact

  • A. Jafari · B. Stoffels · J.C. Kalff · S. Manekeller
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    ABSTRACT: Background: The biliary anastomosis remains to be the Achilles’ heel of liver transplantation. The incidence of biliary complications (e.g., stenosis and leakage) is immanent and the optimal type of reconstruction is unclear. The aim of this study was to compare 2 different bile duct suture techniques regarding their benefits in the prevention of biliary complications. Material/Methods: From 1992 to 2012, the transplanted patients (n=394) of our center were analyzed retrospectively in terms of suture techniques and consecutive biliary complications. Secondary, possible risk factors (cold ischemic time, donor age, and preoperative liver function) were examined. An end-to-end choledocho-choledochostomy without T-tube was performed during orthotopic liver transplantation whenever possible. In group 1 (n=123) the biliary reconstruction was performed completely by continuous-suture technique. In group 2 (n=164) continuous- suture technique was also performed in posterior wall of the bile duct, but the anterior wall was closed by interrupted-suture technique. Results: The overall biliary complication rate was 19.6%. There were no significant differences in biliary complications between the groups. Analysis of risk factors showed no influence on the complication rate. Conclusions: The argument for the interrupted-suture technique is a better overview and a lower risk to grab the posterior wall during the anastomotic realization. The threads of the anterior wall can be presented individually and then be knotted.
    No preview · Article · Jan 2016

  • No preview · Article · Nov 2015 · Zeitschrift für Geburtshilfe und Neonatologie
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    ABSTRACT: Einleitung: Cervicale Ösophagusperforationen sind ein insgesamt seltenes Krankheitsbild und treten meist iatrogen im Rahmen von Diagnostik und Interventionen im Bereich des oberen Gastrointestinaltraktes auf. Aufgrund der Lokalisation und der hohen Morbidität sind eine schnelle Diagnostik sowie eine suffiziente Therapie entscheidend für das weitere Outcome der Patienten. Ziele und Methodik: Es wird die Diagnostik und Therapie, hierbei insbesondere das operativ technische Vorgehen, anhand zweier Fälle vorgestellt und anhand der verfügbaren Literatur diskutiert. Ergebnis: Bei zwei Patienten war es im Rahmen einer transösophagealen Echokardiographie (TEE) ex domo zu einer Perforation im Bereich des cervikalen Ösophagus gekommen. Initial waren die Patienten asymptomatisch, zeigten aber im Verlauf starke Schmerzen, den Nachweis eines Pneumomediastinums in der Bildgebung sowie die Entwicklung einer Sepsis.Daraufhin erfolgte die notfallmäßige Verlegung in unsere Klinik zur operativen Versorgung mittels Exploration, direkter Naht der Perforation und anschließender Plastik mit einem gestielten Sternocleidomastoideus-Lappen. In beiden Fällen konnte ein primärer Verschluss des Defekts und eine Stabilisierung der Patienten erreicht werden. Schlussfolgerung: Aufgrund immer häufigerer Diagnostik und Interventionen im Bereich des oberen Gastrointestinaltraktes steigt einhergehend damit die Komplikationswahrscheinlichkeit sowie -rate an. Bei einer entsprechenden postinterventionellen Symptomatik sollte auch an eine cervicale Ösophagusperforation gedacht und eine umgehende Diagnostik sowie ggf. die operative Behandlung eingeleitet werden.
    Full-text · Conference Paper · Oct 2015
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    ABSTRACT: Background The pathophysiology of adhesion formation after abdominal and pelvic surgery is still largely unknown. The aim of the study was to investigate the role of macrophage polarization and the effect of peroxisome proliferator-activated receptor (PPAR) stimulation on adhesion formation in an animal model. Methods Peritoneal adhesion formation was induced by the creation of ischaemic buttons within the peritoneal wall and the formation of a colonic anastomosis in wild-type, interleukin (IL) 10-deficient (IL-10(-/-)), IL-4-deficient (IL-4(-/-)) and CD11b-Cre/PPAR(fl/fl) mice. Adhesions were assessed at regular intervals, and cell preparations were isolated from ischaemic buttons and normal peritoneum. These samples were analysed for macrophage differentiation and its markers, and expression of cytokines by quantitative PCR, fluorescence microscopy, arginase activity and pathological examination. Some animals underwent pioglitazone (PPAR- agonist) or vehicle treatment to inhibit adhesion formation. Anastomotic healing was evaluated by bursting pressure measurement and collagen gene expression. ResultsMacrophage M2 marker expression and arginase activity were raised in buttons without adhesions compared with buttons with adhesions. IL-4(-/-) and IL-10(-/-) mice were not affected, whereas CD11b-Cre/PPAR(fl/fl) mice showed decreased arginase activity and increased adhesion formation. Perioperative pioglitazone treatment increased arginase activity and decreased adhesion formation in wild-type but not CD11b-Cre/PPAR(fl/fl) mice. Pioglitazone had no effect on anastomotic healing. Conclusion Endogenous macrophage-specific PPAR- signalling affected arginase activity and macrophage polarization, and counter-regulated peritoneal adhesion manifestation. Pharmacological PPAR- agonism induced a shift towards macrophage M2 polarization and ameliorated adhesion formation in a macrophage-dependent manner. Postoperative adhesion formation is frequently seen after abdominal surgery and occurs in response to peritoneal trauma. The pathogenesis is still unknown but includes an imbalance in fibrinolysis, collagen production and inflammatory mechanisms. Little is known about the role of macrophages during adhesion formation. In an experimental model, macrophage M2 marker expression was associated with reduced peritoneal adhesion formation and involved PPAR--mediated arginase activity. Macrophage-specific PPAR- deficiency resulted in reduced arginase activity and aggravated adhesion formation. Pioglitazone, a PPAR- agonist, induced M2 polarization and reduced postoperative adhesion formation without compromising anastomotic healing in mice. Pioglitazone ameliorated postoperative adhesion formation without compromising intestinal wound healing. Therefore, perioperative PPAR- agonism might be a promising strategy for prevention of adhesion formation after abdominal surgery. It's all about macrophages
    No preview · Article · Aug 2015 · British Journal of Surgery
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    Full-text · Article · Aug 2015 · Zeitschrift für Gastroenterologie
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    ABSTRACT: Background: Enteral nutrition is vital for patients with inadequate or absent oral food intake, as it can help to avoid catabolic metabolism. Enteral feeding can be secured by placing a percutaneous endoscopic gastrostomy tube (PEG-tube) which is an approved method. Several clinical studies could verify the superiority of this procedure compared to other options. Even though PEG-tube placement is regarded as less invasive surgery, a considerable rate of complications is reported in literature. Material/Methods: Here, we report a retrospective analysis of PEG-tube placements in the Bonn University Hospital from January 2005 to December 2012. Results: Overall, 641 PEG-tubes were placed with a complication rate of 9.4 %, which can be further divided in 5.5 % minor complications (mic) and 3.9 % major complications (mac). Two cases of death occurred in the context of PEG-tube placement. Endoscopically inserted PEG-tubes showed a complication rate of 8.6 % (4.8 % mic, 3.8 % mac). 63.2 % of mac consisted of perforations, 15.8 % of intra-abdominal abscesses and 15.8 % of buried bumper syndromes. The complication rate of CT-guided placement of PEG-tubes was 38.9 % (27.8 % mic, 11.1 % mac). In this group, all mac were perforations. Surgical PEG-tube placement was accompanied by no mac and 7.7 % mic. Conclusion: The amount of complications during PEG-tube placement is remarkable, therefore the indication of this procedure must be contemplated critically and careful follow-up is crucial. Georg Thieme Verlag KG Stuttgart · New York.
    No preview · Article · Aug 2015 · Zentralblatt für Chirurgie
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    ABSTRACT: To assess pancreatic fistula rate and secondary endpoints after pancreatogastrostomy (PG) versus pancreatojejunostomy (PJ) for reconstruction in pancreatoduodenectomy in the setting of a multicenter randomized controlled trial. PJ and PG are established methods for reconstruction in pancreatoduodenectomy. Recent prospective trials suggest superiority of the PG regarding perioperative complications. A multicenter prospective randomized controlled trial comparing PG with PJ was conducted involving 14 German high-volume academic centers for pancreatic surgery. The primary endpoint was clinically relevant postoperative pancreatic fistula. Secondary endpoints comprised perioperative outcome and pancreatic function and quality of life measured at 6 and 12 months of follow-up. From May 2011 to December 2012, 440 patients were randomized, and 320 were included in the intention-to-treat analysis. There was no significant difference in the rate of grade B/C fistula after PG versus PJ (20% vs 22%, P = 0.617). The overall incidence of grade B/C fistula was 21%, and the in-hospital mortality was 6%. Multivariate analysis of the primary endpoint disclosed soft pancreatic texture (odds ratio: 2.1, P = 0.016) as the only independent risk factor. Compared with PJ, PG was associated with an increased rate of grade A/B bleeding events, perioperative stroke, less enzyme supplementation at 6 months, and improved results in some quality of life parameters. The rate of grade B/C fistula after PG versus PJ was not different. There were more postoperative bleeding events with PG. Perioperative morbidity and mortality of pancreatoduodenectomy seem to be underestimated, even in the high-volume center setting.This is an open-access article distributed under the terms of the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License, where it is permissible to download and share the work provided it is properly cited. The work cannot be changed in any way or used commercially.
    Full-text · Article · Jul 2015 · Annals of surgery
  • A. Koscielny · M. Kühnel · F. Verrel · U. Kania · J.C. Kalff
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    ABSTRACT: The ruptured abdominal aortic aneurysm (rAAA) is still a big challenge for each vascular surgeon. Despite of optimised perioperative management in diagnostics and intensive care there has not been a remarkable improvement in the mortality rates of rAAA. The systematic ultrasonographic screening for asymptomatic AAA in the population aged over 65 years and the centralised treatment of rAAA in high-volume vascular surgery departments play an important role in the reduction of rAAA's mortality. The high mortality of rAAA is caused by the hemorrhagic shock and is sequelae with mainly non-surgical complications. Therapeutic efforts should focus on perioperative factors which could be optimised. Further clinical investigations should elucidate the possibly advantageous implementation of EVAR (endovascular aneurysm repair) in the treatment of rAAA.
    No preview · Article · Jun 2015 · Chirurgische Praxis
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    ABSTRACT: Abdominal surgery results in neuronal mediator release and subsequent acute intestinal hypomotility. This phase is followed by a longer lasting inflammatory phase resulting in postoperative ileus (POI). Calcitonin gene-related peptide (CGRP) has been shown to induce motility disturbances and in addition may be a candidate mediator to elicit neurogenic inflammation. We hypothesized that CGRP contributes to intestinal inflammation and POI. The effect of CGRP in POI was tested in mice treated with the highly specific CGRP receptor antagonist BIBN4096BS and in CGRP receptor-deficient (RAMP-1(-/-) ) mice. POI severity was analyzed by cytokine expression, muscular inflammation and gastrointestinal (GI) transit. Peritoneal and muscularis macrophages and mast cells were analyzed for CGRP receptor expression and functional response to CGRP stimulation. Intestinal manipulation (IM) resulted in CGRP release from myenteric nerves, and a concurrent increased interleukin (IL)-6 and IL-1β transcription and leukocyte infiltration in the muscularis externa and increased GI transit time. CGRP potentiates IM-induced cytokine transcription within the muscularis externa and peritoneal macrophages. BIBN4096BS reduced cytokine levels and leukocyte infiltration and normalized GI transit. RAMP1(-/-) mice showed a significantly reduced leukocyte influx. CGRP receptor was expressed in muscularis and peritoneal macrophages but not mast cells. CGRP mediated macrophage activation but failed to induce mast cell degranulation and cytokine expression. CGRP is immediately released during abdominal surgery and induces a neurogenic inflammation via activation of abdominal macrophages. BIBN4096BS prevented IM-induced inflammation and restored GI motility. These findings suggest that CGRP receptor antagonism could be instrumental in the prevention of POI. © 2015 John Wiley & Sons Ltd.
    No preview · Article · Apr 2015 · Neurogastroenterology and Motility
  • T O Vilz · J Funke · D Pantelis · P Lingohr · M Wolff · J C Kalff · N Schäfer
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    ABSTRACT: Background: Carcinoma of ampulla of Vater are rare tumours of the GI-tract with an improved prognosis compared to other periampullary tumours. Analysis of survival and prognostic factors are limited due to the low incidence of the carcinoma. The intention of this study in patients with papillary carcinoma was to evaluate short- and long-term survival and to identify prognostic factors for pancreatectomy and reconstruction using pancreatogastrostomy as treatment of carcinoma of Vater's ampulla. Patients and Methods: Between 1989 and 2008 76 patients with a carcinoma of the ampulla of Vater were treated by oncological resection followed by pancreatogastrostomy. Various factors such as demographics, perioperative factors, histopathological findings as well as short- and long-term survival were evaluated retrospectively. Data were analysed statistically using Kaplan-Meier estimates of survival with log-rank test and uni- and multivariate analysis with Cox regression. Results: The overall 5-year survival was 46 %, the 10-year survival 26 % for resected patients. By univariate analysis we could demonstrate that lymph node metastasis is the only predictor for outcome. In the multivariate analysis, age, sex, grading and especially lymph node status were a significant predictor for the survival of patients. Conclusion: In the current patient cohort lymph node status was the most important independent predictor of outcome after resection of carcinoma of Vater's papilla. Georg Thieme Verlag KG Stuttgart · New York.
    No preview · Article · Apr 2015 · Zentralblatt für Chirurgie
  • S. Manekeller · J.C. Kalff
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    ABSTRACT: Das maligne Dünndarmkarzinom ist mit 3-5 % aller malignen Tumoren des Gastrointestinaltrakts ein seltener Tumor. Aufgrund seiner unspezifischen Symptomatik wird es zumeist erst im fortgeschrittenen Stadium diagnostiziert. Eine radikale onkologische Resektion in Kombination mit einer adjuvanten Chemotherapie ist die Grundlage für eine potenzielle Heilung und für eine Minimierung des Rezidivrisikos. Aufgrund der Lokalisation und Anatomie des Dünndarms erfolgt die Resektion in den meisten Fällen zur Diagnostik und Therapie. Im fortgeschrittenen Stadium kann, wenn notwendig, eine palliative Resektion und Chemotherapie die Überlebenszeit verlängern. Aufgrund des seltenen Auftretens dieser Tumorentität fehlt es an prospektiv randomisierten Studien zur Optimierung der vorhandenen Therapiekonzepte. Abstract Small intestine cancer is a rare tumor entity accounting for 3-5 % of all gastrointestinal malignancies. As specific symptoms are lacking the first diagnosis is mostly made at an advanced tumor stage. The combination of surgical resection and adjuvant chemotherapeutic treatment is essential for a potentially curative approach and to minimize the risk of recurrence. Surgical exploration and resection are often carried out as a diagnostic and therapeutic approach due to the clinical course of the disease, localization and anatomy of the small bowel. So far, there are no prospective randomized clinical trials to optimize current therapeutic concepts.
    No preview · Article · Apr 2015 · Der Onkologe
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    ABSTRACT: Background: In recent years there has been a significant increase of surgical procedures worldwide. Perioperative complication occurred in approximately 10 %, mortality was about 0.5 %. Half of these adverse events were considered to have been preventable. With the introduction of a perioperative checklist by the WHO in 2008, a significant reduction of morbidity and mortality could be achieved. The aim of this study was to investigate the success of the implementation process of the checklist at a maximum care hospital over a three-year period and to expose and analyse any occurring issues. Patients and Methods: At various time points (introduction phase, five months, one year and three years after implementation) a total of 358 operations was investigated. First the presence and the handling of the checklist were investigated followed by an analysis of possible influencing factors on the processing. To examine a potential perioperative malpractice, three typical perioperative errors known from the literature on patient safety were analysed. Results: The presence of the checklist improved significantly during the study. With the exception of the first column (signed by ward nurse) the checklist was processed more often among the participants (anaesthesia nurse, anaesthesia physician, surgeon) over the time. However the "sign out" column edited by the surgeon at the end of the operation fell below expectations. In addition to the duration after implementation the level of experience of the surgeon was a relevant factor for a properly completed checklist. During the study a malpractice was found in two cases, a checklist could not be detected. Conclusion: Within the study we could demonstrate the difficulties of introducing a surgical checklist at a maximum care hospital. Therefore involved nursing or medical staff must be aware of the usefulness of the checklist and should be motivated to use it. In addition, periodical lectures, training courses and role modelling of nursing and medical staff are required. The objective must be to establish the checklist into daily routine as it is a simple and efficient tool to reduce perioperative morbidity and mortality. Georg Thieme Verlag KG Stuttgart · New York.
    No preview · Article · Feb 2015 · Zentralblatt fur Chirurgie, Supplement
  • G Hong · T O Vilz · J C Kalff · S Wehner
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    ABSTRACT: Die Ausbildung postoperativer peritonealer Adhäsionen ist eine häufige Folge abdominalchirurgischer Eingriffe. Daraus können akute und chronische Beschwerden entstehen, die häufig nur durch eine chirurgische Adhäsiolyse behoben werden können. Dies birgt jedoch das Risiko einer erneuten Adhäsionsbildung. Trotz enormer Fortschritte in der perioperativen Medizin stehen nach wie vor nur eingeschränkte Möglichkeiten der Adhäsionsprophylaxe zur Verfügung. Die atraumatische Chirurgie nimmt dabei immer noch den höchsten Stellenwert ein. Die aktuelle Forschung beschäftigt sich mit zwei Konzepten zur Adhäsionsprophylaxe: dem Einsatz von Barrieren zur Vermeidung des Aneinanderlagerns verletzter Oberflächen in der Bauchhöhle sowie neuen immunmodulatorischen Konzepten. Trotz vielversprechender experimenteller Daten ist die klinische Studienlage zu den Barrierekonzepten sehr heterogen. Die Daten zur Entzündungsmodulation und zugleich Beeinflussung der fibrinolytischen Kapazität sind vielversprechender, meist jedoch noch experimenteller Natur. In dem vorliegenden Artikel soll ein kurzer Überblick über die aktuellen Forschungsergebnisse zur Pathophysiologie und Adhäsionsprophylaxe gegeben werden. Die Daten zeigen die Notwendigkeit der Durchführung solider klinischer Studien und sollen zu deren Durchführung ermutigen.
    No preview · Article · Feb 2015 · Der Chirurg

  • No preview · Article · Sep 2014 · Geburtshilfe und Frauenheilkunde

  • No preview · Article · Aug 2014 · Zeitschrift für Gastroenterologie

  • No preview · Article · Aug 2014 · Zeitschrift für Gastroenterologie
  • T.O. Vilz · J.-C. Schewe · J.C. Kalff · D. Pantelis
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    ABSTRACT: Hintergrund Entscheidend für das Outcome nach plötzlichem Herztod ist die Qualität der Reanimation (CPR), v. a. der Thoraxkompression. Insbesondere bei CPR unter schwierigen Bedingungen haben mechanische Reanimationssysteme (MRD) mittlerweile eine weite Verbreitung gefunden. Schwerwiegende Verletzungen durch die Anwendung sind hierbei selten und in der Literatur ähnlich häufig wie bei manueller Thoraxkompression beschrieben. Dennoch können solche Verletzungen besonders im Postreanimationssetting bedrohlich werden und möglicherweise dem jeweils spezifischen Funktionsprinzip der MRD zugeordnet werden. Ziel des Beitrags Berichtet wird über einen Patienten nach plötzlichem Herztod und CPR mittels MRD, der nach erfolgreicher Koronarintervention einen hypovolämischen Schock entwickelte. Als ursächlich hierfür wurde eine Leberdekapsulierung identifiziert, die am ehesten dem spezifischen mechanischen Funktionsprinzip eines MRD zugeordnet werden konnte. Es sollte daher nach jeder Reanimation mittels MRD eine FAST-Sonographie nach Eintreffen im Schockraum und eine Verlaufskontrolle einige Stunden nach Stabilisierung des Patienten erfolgen.
    No preview · Article · May 2014 · Notfall
  • T O Vilz · S Wehner · D Pantelis · J C Kalff
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    ABSTRACT: Postoperative ileus (POI) is defined as a transient episode of impaired gastrointestinal motility after abdominal surgery, which prevents effective transit of intestinal contents or tolerance of oral intake. This frequent postoperative complication is accompanied by a considerable increase in morbidity and hospitalisation costs. The aetiology of POI is multifactorial. Besides a suppression of peristalsis by inhibitory neuronal signalling and administration of opioids, particularly in the prolonged form, immunological processes play an important role. After surgical trauma, resident macrophages of the muscularis externa (ME) are activated leading to the liberation of proinflammatory mediators and a spreading of the inflammation along the entire gastrointestinal tract. To date, no prophylaxis or evidence-based single approach exists to treat POI. Since none of the current treatment approaches (i.e., prokinetic drug treatment) has provided a benefit in randomised trials, immunoregulatory interventions appear to be more promising in POI prevention or treatment. The present contribution gives an overview of immunological mechanisms leading to POI focusing on current and future therapeutic and prophylactic approaches.
    No preview · Article · Dec 2013 · Zentralblatt für Chirurgie
  • N. Vetter · A. Koscielny · N. Schäfer · J.C. Kalff · J. Standop
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    ABSTRACT: Background Totally implantable venous access devices (TIVAD), also referred to as Port-a-Cath systems, are widely used for chronically ill and cancer patients. The choice of insertion modalities and sites is usually empirical, and only limited general recommendations are available. Patients and methods In all, the records of 154 patient after TIVAD implantation were reviewed to determine the rates of complications and reoperations as well as longevity with a median follow-up of 541 days (“as-treated” analysis). Patients were grouped according to the access route: percutaneous landmark access to the internal jugular (n = 71) vs. subclavian vein (n = 32; Seldinger technique) vs. surgical cutdown access through the cephalic vein at the deltoid–pectoralis groove (n = 51). Results No significant differences were found regarding the reoperation rate: internal jugular (15.5 %) vs. cephalic (15.7 %) vs. subclavian (9.4 %). Early complications were dominated by hemorrhage. Catheter or chamber infection was the most common complication during follow-up. Percentage of patients with at least one complication was 17.7 % after cephalic vs. 15.5 % after internal jugular vs. 9.4 % after subclavian vein access, respectively. The 3-year survival of the ports was 69.5 % (internal jugular vein) compared to 82.1 % (subclavian vein) after percutaneous cannulation vs. 76.9 % in patients with surgical cutdown access. There were no statistically significant differences regarding early and late complications as well as 3-year TIVAD survival according to the access route. Conclusion Due to the retrospective study design, interpretation of absolute complications rates is somewhat limited. Nevertheless, the access route for TIVAD implantation has no significant impact on early or late complications as well as longevity. Regardless of the implantation technique, catheter infection was the most common complication with subsequent need for port removal. We favor a surgical cutdown attempt because of the mandatory incision to implant the chamber in any case. In case of failure, the incision access can be used for direct puncture of the subclavian vein.
    No preview · Article · Dec 2013 · Gefässchirurgie
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    ABSTRACT: As data about prevalence and standard of care in short bowel syndrome (SBS) are not available for Germany, this study estimated the prevalence and assessed the medical infrastructure to potentially improve care of SBS patients. In a validated approach for prevalence estimation in rare diseases, a randomized census of 478 size-stratified hospitals with surgical, internal medicine and pediatric departments was conducted to estimate SBS prevalence. The number of SBS patients, specialized outpatient clinics and caregiver expertise were assessed. The response rate was 85 % of randomized hospitals (405/478). Strata-derived estimation yielded a total of 2,808 SBS patients in Germany for 2011/2012 (95 % CI: 1750.3865), translating into a prevalence estimation for 34/million inhabitants (95 % CI: 21.47). Overall expertise in SBS treatment was only rated "satisfactory" by most caregivers. While 86 specialized outpatient clinics were identified, there was no central registry to access these resources. Short bowel syndrome, with a newly estimated prevalence of 34/million inhabitants is not a very rare medical condition in Germany. The interdisciplinary approach needed for optimal care for SBS patients would be greatly facilitated by a central registry.
    No preview · Article · Nov 2013 · Der Chirurg

Publication Stats

845 Citations
235.67 Total Impact Points


  • 1998-2015
    • University of Bonn
      • • Faculty of Medicine
      • • Klinik und Poliklinik für Herzchirurgie
      Bonn, North Rhine-Westphalia, Germany
  • 2006-2011
    • University of Bonn - Medical Center
      Bonn, North Rhine-Westphalia, Germany
  • 1997-2002
    • University of Pittsburgh
      • • Department of Medicine
      • • Department of Surgery
      Pittsburgh, Pennsylvania, United States