Slackia exigua, originally classified as Eubacterium exiguum, is a Gram-positive, asaccharolytic, rod-shaped anaerobic bacterium. The virulence factors of S. exigua have not been accurately identified. The objective of the study is to evaluate the pathogenic potential of S. exigua by presenting the cases of infections diagnosed at our hospital laboratory. Additionally, we reviewed the literature to summarize the experience with S. exigua infections to clarify, in the light of current knowledge, the clinical picture, diagnostic, and therapeutic issues related to this anaerobic bacterium. We reported eleven severe human infections caused by S. exigua. All patients required hospitalization. Nine of the cases involved chronic infections in the stomatognathic system, in two patients, skin infections were diagnosed. As it is known, S. exigua is a component of the human microbiota; however, it can cause opportunistic infections, particularly in the case of translocation outside its natural habitat. A critical literature analysis revealed that S. exigua can be responsible for bacteremia, meningitis, tissue necrosis, periprosthetic joint infection, and osteomyelitis. Several studies have been published regarding the determination of drug susceptibility of S. exigua. The isolated strains were susceptible to most antibiotics used for the treatment of anaerobic infections. The interpretation of antimicrobial susceptibility testing for some slow-growing in vitro, infrequently causing infections anaerobic bacteria, such as S. exigua, is based on The European Committee on Antimicrobial Susceptibility Testing (EUCAST) additional guidance taking into account the determination of drug susceptibility for groups of microorganisms for which cut-off values have not been developed.
We report the design, synthesis, and antimicrobial evaluation of a series of ciprofloxacin (CP) conjugates coupled with nitrogen-containing heterocycles. In vitro screening of these new hybrid compounds (1-13) against a panel of planktonic bacterial strains highlighted thiazolyl homologs 6 and 7 as the most promising candidates for further investigation. These derivatives demonstrated potent growth-inhibitory activity against various standard and clinical isolates, with minimum inhibitory concentrations (MICs) ranging from 0.05 to 0.4 mu g/ml, which are higher or comparable to the reference fluoroquinolone. Both compounds effectively inhibited biofilm formation by selected staphylococci across all tested concentrations (1-8 x MIC), displaying greater efficacy at higher doses compared to CP alone. Notably, conjugate 7 also significantly eradicated existing biofilms formed by S. aureus of various origin. Molecular docking studies revealed that conjugate 7 engages in a broader range of interactions with DNA gyrase and DNA topoisomerase IV than CP, suggesting stronger binding affinity and enhanced flexibility. This may contribute to its potential in overcoming bacterial resistance mechanisms. The above findings indicate compound 7 as a promising candidate for clinical development.
Biofilms are complex, highly organized structures formed by microorganisms, with functional cell arrangements that allow for intricate communication. Severe clinical challenges occur when anaerobic bacterial species establish long-lasting infections, especially those involving biofilms. These infections can occur in device-related settings (e.g., implants) as well as in non-device-related conditions (e.g., inflammatory bowel disease). Within biofilms, bacterial cells communicate by producing and detecting extracellular signals, particularly through specific small signaling molecules known as autoinducers. These quorum-sensing signals are crucial in all steps of biofilm formation: initial adhesion, maturation, and dispersion, triggering gene expression that coordinates bacterial virulence factors, stimulates immune responses in host tissues, and contributes to antibiotic resistance development. Within anaerobic biofilms, bacteria communicate via quorum-sensing molecules such as N-Acyl homoserine lactones (AHLs), autoinducer-2 (AI-2), and antimicrobial molecules (autoinducing peptides, AIPs). To effectively combat pathogenic biofilms, understanding biofilm formation mechanisms and bacterial interactions is essential. The strategy to disrupt quorum sensing, termed quorum quenching, involves methods like inactivating or enzymatically degrading signaling molecules, competing with signaling molecules for binding sites, or noncompetitively binding to receptors, and blocking signal transduction pathways. In this review, we comprehensively analyzed the fundamental molecular mechanisms of quorum sensing in biofilms formed by anaerobic bacteria. We also highlight quorum quenching as a promising strategy to manage bacterial infections associated with anaerobic bacterial biofilms.
Staphylococcus pettenkoferi is a coagulase-negative staphylococcus, first described in 2002. Using medical databases, i.e., Scopus, Web of Science, Pubmed, and Embase, we identified and analysed research, reports, and opinions dealing with S. pettenkoferi. Published data allow us to conclude that S. pettenkoferi is a human commensal, opportunistic bacterium and may be isolated from the environment and animals. The involvement of S. pettenkoferi in bloodstream infection and osteomyelitis has been described, but its clinical relevance is not fully understood, so far. This work summarizes knowledge about S. pettenkoferi and reveals the difficulties and rules for interpreting the results of microbiological tests, when S. pettenkoferi has been identified in the blood sample. Clinical and laboratory criteria, recommended by Centers for Disease Control and Prevention (CDC) and the third international consensus definitions of sepsis and septic shock (Sepsis-3), are important to determine whether the presence of bacteria in the sample is a consequence of an infection, contamination from the environment, or translocation of the bacteria outside the place of its natural existence. The precise identification of bacteria from the blood sample and recognizing the true bacteraemia are critical to implement the appropriate procedures and make decisions concerning the patient's medical care.
Staphylococcus pettenkoferi was first isolated from blood culture a 25-years-old patient with fever of unknown etiology. Based on the literature analysis, it was found that it is an opportunistic microorganism. It causes blood stream infections and was an causative agent of osteomyelitis. Staphylococcus pettenkoferi is a component of the human microbiome, was found in a hospital environment and was also isolated from animals and their surroundings.
Introduction and objective. Studies on occupational exposure to adverse conditions usually focus on professional groups, such as doctors, nurses and laboratory workers. Researchers have also drawn attention to the dangers threatening paramedics while performing their duties. The aim of this study is to analyze the occupational exposure of paramedics to hepatitis B and C viruses, to identify the activities during which occupational exposure occurs most frequently, and to analyze the possibility of protecting a paramedic from occupational exposure to infection. Review methods. The publication was prepared based on a literature review in available scientific information databases and on the websites of organizations operating in the field of
Staphylococcus pettenkoferi is a coagulase negative staphylococcus (CoNS) whose clinical relevance is not fully understood. Hitherto, there are several reports describing the participation of this species in human infections; in most cases S. pettenkoferi was isolated from blood cultures. The purpose of this work is to summarize knowledge about S. pettenkoferi especially in terms of biochemical properties, types of infections caused, factors predisposing to bacteremia and susceptibility to antibiotics. Particular attention was paid to the difficulties in identifying this CoNS bacterium and limitations of microbiological tests. The principles of microbiological bloodstream infection diagnostics and criteria for interpreting test results are summarized, as well. The analysis of published reports and opinions resulted in better characterization of infections in which S. pettenkoferi is the etiological agent. From a clinical point of view, presented knowledge allows to assess the risk of bloodstream infection or sample contamination, help physician to implement the appropriate procedures and making decisions concerning inter alia empirical treatment.