Characterization of the gut microbiota in patients with primary sclerosing cholangitis compared to inflammatory bowel disease and healthy controls.

BACKGROUND: Primary sclerosing cholangitis (PSC) is a chronic cholestatic liver disease. Its etiology remains largely unknown, although frequent concomitant inflammatory bowel disease (IBD) hints towards common factors underlying intestinal and bile duct inflammation. Herein, we aimed to explore the relative abundance of fecal microbiota in PSC-IBD patients compared to IBD-only subjects and controls. METHODS AND RESULTS: We included 14 PSC-IBD patients, 12 IBD-only patients, and 8 healthy controls (HCs). A quantitative real-time PCR (qPCR) assay was used to determine a selection of bacterial phyla, families, and genera. Relative abundance of taxa showed that Bacteroidetes was the most abundant phylum among the patients with PSC-IBD (29.46%) and also HCs (39.34%), whereas the bacterial species belonging to the phylum Firmicutes were the most frequent group in IBD-only subjects (37.61%). The relative abundance of the Enterobacteriaceae family in fecal samples of PSC-IBD patients was similar to those with IBD-only, which was significantly higher than HCs (p value = 0.031), and thus, could be used as a PSC-IBD or IBD-only associated microbial signature. CONCLUSIONS: Our findings showed that intestinal microbiota composition in PSC-IBD patients was completely different from that of IBD-only patients. Further studies using large-scale cohorts should be performed to better describe the contribution of the gut microbiota to PSC pathogenesis with underlying IBD.

A comprehensive review of bacterial osteomyelitis with emphasis on Staphylococcus aureus.

Osteomyelitis, a significant infection of bone tissue, gives rise to two main groups of infection: acute and chronic. These groups are further categorized in terms of the duration of infection. Usually, children and adults are more susceptible to acute and chronic infections, respectively. The aforementioned groups of osteomyelitis share almost 80% of the corresponding bacterial pathogens. Among all bacteria, Staphylococcus aureus (S. aureus) is a significant pathogen and is associated with a high range of osteomyelitis symptoms. S. aureus has many strategies for interacting with host cells including Small Colony Variant (SCV), biofilm formation, and toxin secretion. In addition, it induces an inflammatory response and causes host cell death by apoptosis and necrosis. However, any possible step to take in this respect is dependent on the conditions and host responses. In the absence of any immune responses and antibiotics, bacteria actively duplicate themselves; however, in the presence of phagocytic cell and harassing conditions, they turn into a SCV, remaining sustainable for a long time. SCV is characterized by notable advantages such as (a) intracellular life that mediates a dam against immune cells and (b) low ATP production that mediates resistance against antibiotics.