Endoscopic Evaluation in Transplantation Candidates
Condition: Liver Transplantation
Study type: Observational

Summary: 
      In consideration of the limited supply of donor organs, the careful selection of transplant
      candidates is essential to optimize patient outcome after transplantation. Therefore an
      extensive evaluation of transplant candidates including among others
      esophagogastroduodenoscopy (EGD) and colonoscopy has been implemented in our centre. The data
      regarding the prevalence of upper and lower gastrointestinal (GI) pathology in transplant
      candidates are contradictory and are based on only a few retrospective studies, which often
      include only a subgroup of transplant candidates. The goal of this project is a prospective
      evaluation of the frequency of GI pathologies in transplant candidates with specific focus on
      the following questions:

        1. Are there GI-pathologies that occur at a higher prevalence in transplant candidates than
           described in the general population and is there an increase of GI-pathologies since the
           introduction of the urgency-based organ allocation leading to sicker transplant
           candidates?

        2. What is the influence of endoscopic findings on patient management before
           transplantation?

        3. Which risk factors can be identified that predict the presence of GI-lesions?

        4. Is there a subgroup of patients, in which screening colonoscopy before liver
           transplantation can not be recommended considering the cost/benefit ratio?

        5. Is there a correlation of endoscopic findings with outcome after liver transplantation
           or with gastrointestinal complications during or after transplantation (e.g.
           gastrointestinal bleeding, perforation or gastrointestinal malignancy)?
    

Detailed description: 
      Background:

      The introduction of a MELD (model for end-stage liver disease) based necessity-oriented
      allocation system for liver transplantation (OLT) has lead to an increasing number of
      patients with advanced liver disease on the waiting list. Hence it is essential to optimize
      outcome after transplantation in this high-risk patient collective in order to best utilize
      the limited supply of donor organs. To achieve this goal, the careful selection of
      appropriate transplantation candidates is based on an extensive evaluation of the patients
      including cardiac, pulmonary and renal testing and different imaging methods to exclude
      malignancies or an infective focus. As in many other institutions also in the Medical School
      Hannover (MHH) esophagogastroduodenoscopy (EGD) and colonoscopy are standard procedures
      during evaluation for liver transplantation. The rationale to perform these procedures is to
      identify patients with medical conditions that might limit their outcome after OLT. Some
      endoscopic findings as for example esophageal varices, gastric or duodenal ulcer or colon
      adenoma can be treated before transplantation, so that the patient enters the waiting list in
      a better medical condition. If gastrointestinal malignancies are detected, the patient will
      no longer be considered a candidate for OLT, unless curative treated. The detection of
      premalignant changes (high grade adenomas, barrett's esophagus etc.) is of great importance,
      since the immunosuppressed liver transplantation recipients are probably at a higher risk to
      progress to malignancy.

      So far the data regarding the prevalence of upper and lower gastrointestinal pathologies in
      transplantation candidates are contradictory and are based on only a few retrospective
      studies. These studies often include only a subgroup of transplantation candidates. Many
      centres perform screening colonoscopy during OLT evaluation only in patients greater than age
      45 or 50, although until today there is no clear evidence, that younger patients do not have
      a benefit from screening colonoscopy.

      So far it is not known if certain preoperative endoscopic findings correlate with
      postoperative gastrointestinal complications. Such a correlation, e.g. between diverticulosis
      and postoperative colon perforation or peritonitis due to diverticulitis, could be highly
      relevant for patient management before and after OLT.

      Methods:

      After signing informed consent the results of EGD and colonoscopy of all patients evaluated
      for OLT at the MHH together with laboratory and clinical data will be entered in a database.
      After follow up for at least one year these data will be analyzed. Descriptive statistics as
      well as a multivariate analysis will be performed, to find out the frequency of endoscopic
      diagnoses in transplantation candidates and to look for correlations between these findings
      and patient outcome after OLT.
    

Observational model: Cohort
Time perspective: Prospective
Sampling method: Non-Probability Sample
Study population: 
        Patients evaluated for Tranplantation at Hannover Medical School
      
Keywords: Transplantation; Liver; Endoscopy; Colonoscopy; Gastroscopy