A Case of a Rare, Incidental Discovery of Fibrous Obliteration of an Appendiceal Diverticulum.

Diverticulosis of the appendix (DA) is rare and frequently found incidentally. Some cases are discovered after presenting with similar symptomatology to acute appendicitis, whereas other cases may be completely silent. Fibrous obliteration (FO) is a histologic finding indicative of cellular proliferation secondary to relapses of subclinical inflammatory processes. We report a case of a 75-year-old female with a history of chronic, intermittent abdominal pains who presented to the general surgery clinic after an abnormal thickening of the appendix was discovered on abdominal and pelvic computed tomography imaging. The patient underwent laparoscopic appendectomy for suspicion of malignancy. The histologic evaluation of the specimen demonstrated a diverticulum at the distal end of the appendix with FO of the lumen. We suspect the chronic nature of her disease course may have led to the FO of the diverticulum. An extensive literature search was performed, which revealed no other cases of FO of appendiceal diverticula. This may be the first case of diverticulosis of the appendix with FO in the English medical literature. If DA is discovered early with non-invasive imaging, surgical excision should be performed prophylactically as an association with an increased risk of perforation and neoplastic progression has been found.

Exogenous fatty acids alter phospholipid composition, membrane permeability, capacity for biofilm formation, and antimicrobial peptide susceptibility in Klebsiella pneumoniae.

Klebsiella pneumoniae represents a major threat to human health due to a combination of its nosocomial emergence and a propensity for acquiring antibiotic resistance. Dissemination of the bacteria from its native intestinal location creates severe, complicated infections that are particularly problematic in healthcare settings. Thus, there is an urgency for identifying novel treatment regimens as the incidence of highly antibiotic-resistant bacteria rises. Recent findings have highlighted the ability of some Gram-negative bacteria to utilize exogenous fatty acids in ways that modify membrane phospholipids and influence virulence phenotypes, such as biofilm formation and antibiotic resistance. This study explores the ability of K. pneumoniae to assimilate and respond to exogenous fatty acids. The combination of thin-layer chromatography liquid chromatography-mass spectrometry confirmed adoption of numerous exogenous polyunsaturated fatty acids (PUFAs) into the phospholipid species of K. pneumoniae. Membrane permeability was variably affected as determined by two dye uptake assays. Furthermore, the availability of many PUFAs lowered the MICs to the antimicrobial peptides polymyxin B and colistin. Biofilm formation was significantly affected depending upon the supplemented fatty acid.