Molecular detection of <i>Salmonella typhi</i> from gallbladder tissue of cholecystitis patients and its relation to gallstone formation

Abstract

<p>The gallbladder is often colonized by <italic>Salmonella</italic> during typhoid fever, and cholelithiasis contributes to many factors one of them is cholecystitis, which results from bacterial infections. This study aims to detect <italic>Salmonella typhi</italic> in the tissue of the gallbladder and find out its role in cholelithiasis. A total of 55 patients undergoing clinical and ultrasound examination were enrolled in this study, 43 with cholelithiasis and 12 without cholelithiasis, in which the gallbladder was taken as part of the surgical treatment for morbid obesity. DNA from tissue was extracted using QIAamp DNA Mini kit (Qiagen GmbH, Hilden, Germany) according to the manufacturer's recommendations; primer sets were used in this study that targeted <italic>fliC</italic> and <italic>SopB</italic> genes. A considerable number of cholelithiasis patients, 35 (81%), presented with multiple stone formation, while 8 (18.6%) presented with single stone formation. As many as 43 (78.1%) of cases presented with chronic cholecystitis, while only 12 (21.8%) of cases presented with acute cholecystitis by sonographic gallbladder; out of 55 samples, 10 (18.1%) were positive for the <italic>fliC</italic> gene in amplification of 367 bp. All 10 positive samples for <italic>Salmonella typhi</italic> showed gallbladder stone formation. However, out of 10 positive tissue samples for <italic>Salmonella typhi</italic> 10 (100%), of them were positive for the <italic>SopB</italic> gene. The findings in this study add to the body of knowledge around the occurrence rate of <italic>Salmonella typhi</italic> in gallbladder tissue samples obtained from patients with cholecystitis.</p>