Bacterial infection in cholecystitis and the pathogenesis factors

Fateme Farahany,1,* Melika amya,2 Negar dayizadeh,3 Neda akbari,4 Karamollah toolabi,5 Parastoo ehsani,6

1. Microbiology Department, Azad University of Arak
2. Molecular biology department, Pasteur Institute of Iran
3. Molecular biology department, Pasteur Institute of Iran
4. Microbiology Department, Azad University of Arak
5. Imam Khomeini Hospital
6. Molecular biology department, Pasteur Institute of Iran

Abstract

Introduction

Cholecystitis is the major form of disease of gallbladder organ. it is caused by obstruction of cystic duct either by gallstones or by bacterial infection. providing the information on the pathogenesis factors is important in the treatment of disease. the aim of this study is to investigate the variety of bacterial agents including non-culturable in cholecystitis. however, the biochemical type of gallstones and some pathogenesis factors of bacteria such as antibiotic resistance and biofilm formation and the genes involved were tested.

Methods

The gallbladder specimens (tissue, bile, and gallstone) were collected following laparoscopic cholecystectomy from 39 patients between 30 – 60 years with cholelithiasis from imam khomeini hospital. the culturable bacteria were identified and for negative cultures, the purified dna from tissue samples were used as template in 16srrna pcr using 1492r and 27f primers. the amplified fragments were sequenced and blasted against ncbi dna library.for isolated e.coli bacteria, the antibiotic susceptibility tests were done and biofilm formation and the genes involved were evaluated by microtiter plate and pcr methods respectively.

Results

S. aureus, e.coli, k.pneumoniae, and enterococcus were the most isolated bacteria. 98% of gallstones were cholesterol and bilirubin form. for the unculturable bacteria, the blast result showed to be mostly klebsiella pneumonia. the antibiotic test showed that e.coli were susceptible to the most of the antibiotics. among e.coli isolates, all of them were able to make biofilm. however, half were strong producer and the rest were medium producer of biofilm.

Conclusion

The prevalence of bacterial infection (culturable and nonculturable) in cholecystitis is important. moreover, data on the biofilm formation and other virulence factors are key elements in treatment strategy for bacterial agents of the cholecystitis.

Keywords

cholecystitis, gallbladder, gallstone, bacterial infection