Cholecystitis From a Microbiological and Histopathological Perspective

Study Overview
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Brief Summary
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The aim of this project is to investigate the presence of bacteria in the gallbladder wall and the bile in patients undergoing cholecystectomy, to determine if the standard empirical antibiotic treatment used currently is effective against the most common pathogens.

Detailed Description
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The investigators will compare two groups of patients; patients with acute calculous cholecystitis undergoing acute laparoscopic cholecystectomy and patients without cholecystitis undergoing elective laparoscopic cholecystectomy. Secondly, the investigators wish to investigate if the presence of bacteria correlates with the grade of inflammation, and whether this can predict when cholecystitis is caused by infection. In a clinical setting, this can provide important knowledge regarding the choice of antibiotics currently used to treat and prevent infection in the gallbladder. The investigators will conduct two studies, one investigating the bacteria in bile and in the gallbladder wall and the resistens of the bacteria to antibiotics and another study investigating the histopathology of the gallbladder wall to see if the bacteria present is the cause of inflammation or an actual infection.

Official Title
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Cholecystitis From a Microbiological and Histopathological Perspective

Conditions
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Calculous Cholecystitis, Antibiotic Resistant Infection, Gallbladder Inflammation

Intervention / Treatment
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* Other: Microbiological and histopathological investigation of bile and gallbladder wall specimens.


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Age above 18 years Signed consent form Patients having cholecystectomy performed at the Department of Surgery, Sygehus Lillebælt, Kolding. Exclusion Criteria: Administration of any type of antibiotics one month prior to surgery in the control group. Previous instrumentation of the bileducts Previous clinical acute cholecystitis treated conservatively with antibiotics Patients will be precluded from the studypopulation in cases of pPerioperative perforation of the gallbladder, or conversion to open cholecystectomy or in cases of failed attempts to extract bile or samples from the gallbladder wall.

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Case group<br>Patients suffering from acute calculous cholecystitis undergoing subacute laparoscopic cholecystectomy. Samples of bile and gallbladder wall specimens will be taken during surgery and will be sent for microbiological and pathological investigation | Other: Microbiological and histopathological investigation of bile and gallbladder wall specimens.<br>* Bile and gallbladder wall specimens will be taken from all patients included in the study. The material will be sent for microbiological and histopathological investigation.<br>|
| Control group<br>Patients suffering from painattacks due to gallstones, who have not symptoms of cholecystitis. The patients will undergo elective laparoscopic cholecystectomy. Samples of bile and gallbladder wall specimens will be taken during surgery and will be sent for microbiological and pathological investigation | Other: Microbiological and histopathological investigation of bile and gallbladder wall specimens.<br>* Bile and gallbladder wall specimens will be taken from all patients included in the study. The material will be sent for microbiological and histopathological investigation.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Bacterial colonization in bile and gallbladder wall samples | Microbiological investigation of microorganisms present in the bile and in the gallbladder wall. Bile samples will be collected by puncturing the gallbladder either perioperatively or immediate after extraction of the gallbladder from the abdomen. This is done in a sterile manner using a syringe. The gallbladder wall specimens are collected immediately after extraction of the gallbladder from the abdomen. Three samples will be taken from macroscopic normal looking parts of the posterior wall in the fundus area using a sterile 4 mm punch biopsy. Bile samples and punch biopsies sent to the Department of Clinical Microbiology, SLB, will be cultured on selected agar growth media and incubated under aerobic, microaerophilic, and anaerobic conditions. Bacterial colonies will be identified and quantified using routine laboratory methods. | 36-72 hours | 
| Antibiotic resistans | Microbiological investigation of antibiotic resistans of the bacteria, if any, present in bile and gallbladder wall specimens. Antimicrobial susceptibility testing will be performed using the disk diffusion method. To determine the possible presence of inhibitory concentrations of antibiotics in the bile samples, a droplet of bile from each sample will be added to an agar plate inoculated with the E. coli ATCC 25922-strain. After incubation, the appearance of a growth inhibition zone will be measured. | 36-72 hours | 
| Histopathology of the gallbladder | Histopathological investigation of the gallbladder to investigate if there is either inflammation or an actual infection and correlate these findings to the bacterial colonization. The gallbladder from all included patients will be sent to the Department of Pathology, SLB, for evaluation of the grade of inflammation. After formalin fixation sections from the cystic duct, the corpus and the fundus area will be sampled. The sections will be embedded in paraffin and will be cut into thin slices, which will be dyed with hematoxylin and eosin. The grade of acute inflammation will be assessed in a semi quantitative manner: Grade 1: superficial ulceration of the mucosa concomitant with light infiltration by neutrophile granulocytes Grade 2: infiltration by granulocytes, spreading into the deeper layers of the gallbladder wall. Grade 3: profound necrosis, extending through the entire gallbladder wall. | 3-21 days |