European journal of microbiology & immunology最新文献

Background: The potential aetiological relevance of Blastocystis spp. and Dientamoeba fragilis in the human intestine, and their possible associations with Campylobacter spp. and Giardia duodenalis, remain unclear. By incorporating Bayesian priors to account for diagnostic test accuracy, we statistically analysed the interactions among these microorganisms.

Methods: Diagnostic test accuracy data were derived from multiple PCR assays and incorporated as priors to adjust for non-differential misclassification. Bayesian odds ratios and relationships based on DNA quantity were assessed for a dataset of 1,065 stool samples containing at least one of the four target microorganisms.

Results: Accounting for diagnostic test accuracy resulted in wide credibility intervals. Blastocystis spp. were negatively associated with G. duodenalis. G. duodenalis was most often detected in the absence of Blastocystis spp. and D. fragilis, whereas detection of Blastocystis spp. was associated with lower Campylobacter spp. DNA abundance. A negative association between Blastocystis spp. and Campylobacter spp. was observed only in the absence of D. fragilis.

Conclusion: The assumed variation in detection rates of Campylobacter spp. and G. duodenalis based on the presence of Blastocystis spp. and/or D. fragilis was confirmed. Future epidemiological studies should explore interactions among multiple microorganisms using robust statistical approaches.

Staphylococcus aureus is a clinically important bacterial pathogen causing infections from superficial skin lesions to life-threatening systemic diseases. The emergence of methicillin-resistant S. aureus (MRSA) has compounded the global health burden, particularly in low- and middle-income countries, as its quorum-sensing (QS) mediated mechanisms contribute to its persistence, resistance, and evasion from host immune responses and antimicrobial treatments. Thus, these features compromise the effectiveness of conventional antibiotics, urging the need for alternative therapeutic approaches. To resolve these issues, several non-antibiotic antibiofilm approaches have been developed. Bacteriophages and phage-derived enzymes show promising specificity in lysing bacterial cells and disrupting biofilms. Antimicrobial peptides (AMPs), with their broad-spectrum activity, destabilize bacterial membranes and modulate immune responses. Monoclonal antibodies can neutralize toxins or inhibit adhesion molecules within biofilms. Phytochemicals have demonstrated activity against QS pathways and efflux pumps. Metal ion chelators like deferiprone interfere with iron acquisition, which is essential for biofilm stability. Nanoparticles (NPs), ranging from metallic and polymeric to lipid-based and cyclodextrin-based systems, enhance drug delivery and biofilm penetration. CRISPR-Cas systems provide precise genome editing to target resistance genes and virulence factors. Rhamnolipids disrupt biofilm matrix integrity, while enzymes such as dispersin B degrade extracellular polymeric substances. Photodynamic and laser therapies offer localized disruption of biofilm structures through oxidative stress. Collectively, this review offers a transformative complementary approach to traditional antibiotics, enhancing treatment efficacy while potentially reducing the emergence of resistance. Continued research on delivery systems, safety profiles, and synergistic combinations will be pivotal for their clinical translation against S. aureus infections.

Background: A cross-sectional study was performed to investigate associations of enteric colonization with resistant bacteria in Ghanaian individuals who were tested positive and negative for the human immunodeficiency virus (HIV).

Methods: Abundance of the ESBL-(extended spectrum beta-lactamase-)type resistance-mediating gene blaCTX-M and the vancomycin resistant enterococci-(VRE-)associated genes vanA and vanB genes was associated with available clinical and epidemiological data on the study participants.

Results: In terms of enteric carriage of ESBL-positive bacteria with CTX-M-type beta-lactam resistance genes, being HIV-positive (93.3% vs. 83.3%, P = 0.003) and having low CD4+ T-lymphocyte counts <200 cells/µL (microliter) (96.8% vs. 91.2%, P = 0.009) were identified as risk factors. Enteric carriage of ESBL-positive bacteria with CTX-M-type resistance genes was associated with poor immunological status in terms of lower CD4+ T-leukocyte counts, lower CD4+/CD8+ ratios, higher viral replication, as well as with immune activation. For VRE, a non-significant trend for more VRE in control individuals without known HIV infection (6% vs. 2.5%, P = 0.089) was observed.

Conclusions: An association of ESBL colonization and immunological status was recorded. No such association was detected for VRE, suggesting different determinants of local VRE epidemiology.

Chronic degenerative diseases including osteoarthritis are on the rise leading to a growing demand for joint replacement surgery in elderly and often multimorbid patients. Periprosthetic joint infections (PJIs) constitute serious complications following endoprosthetic surgery. Increasing prevalences of PJIs by multi-drug resistant and/or biofilm-producing bacteria hinder sufficient anti-infectious treatment especially in vulnerable patients. Hence, alternative and/or adjunct therapeutic approaches appear crucial in the combat of difficult-to-treat PJIs. In our review we summarize recent evidence for changes in the spectrum of PJI-associated pathogens over time and elucidate treatment concepts beyond established standard therapies. Our literature search revealed that the spectrum of bacterial pathogens can vary considerably depending on the time course post-surgery, the geographical region, and the patient population. While standard antibiotic therapy besides surgical revision remains the corner stone of treatment, alternative/adjunct antibiotics-independent methods are increasingly coming to the fore. These include the targeted dissolution of bacterial biofilms, enzyme-based approaches, and enhanced infection prevention measures upon risk assessment of the patient. Despite promising methodological approaches clinical evidence of their therapeutic value in everyday care is scarce. Hence, optimized early pathogen detection measures, individually tailored treatment concepts and their application in interdisciplinary settings will be important in the combat of difficult-to-treat PJIs.

Sexually transmitted infections (STIs) represent a major global health concern, with certain ethnic communities being disproportionately affected. This review summarizes recent evidence of ethnic disparities in STI prevalence and screening rates, with most data originating from the United States. The findings confirm the fact that certain ethnic communities such as Black and Hispanic display higher prevalence rates of STIs. Yet the data on screening behavior reveal a striking contradiction. While some studies report lower testing rates among these communities, others demonstrate that Black and Hispanic individuals reported the highest testing engagement compared to other ethnic groups. If testing behavior alone explained these disparities, a clearer correlation between screening and infection rates would be expected. Instead, that paradox might suggest a complex interplay with additional factors included in this review such as, for example, institutional racism, socioeconomic inequalities, differences in sexual and healthcare-seeking behavior, traumatic experiences, and limited access to healthcare. In conclusion, given the global burden caused by STIs, the ongoing health disparities in many parts of the world indicate an urgent need for further investigations into the mechanisms behind these disparities and to identify factors that yet may have been overlooked.

Background: Actinomyces spp.-associated bloodstream infections have been infrequently described and repeatedly but not exclusively associated with intra-oral infections. For Actinomyces radicidentis, which has been shown to cause biofilm-forming endodontic infections, bacteremia has only once been reported so far. To elaborate on the scarcely available information on potential etiological relevance of A. radicidentis as a cause of bloodstream infection, we describe another case of A. radicidentis bacteremia.

Case report: A. radicidentis confirmed by 16S rRNA gene sequencing was detected in the bloodstream of an 81-year-old male multimorbid patient with diffuse large B-cell lymphoma of non-germinal center type under chemotherapy as the most critical medical condition. A specific focal infection was not recorded. A concomitantly diagnosed Pseudomonas aeruginosa-associated urinary tract infection was treated with piperacillin/tazobactam for 1 day and meropenem for additional 9 days. While the course of the infection was considered as favorable by the clinicians in charge, an unfavorable course of the underlying malignant disease let to demission of the patients for palliative care at home.

Discussion: Although A. radicidentis bacteremia was not specifically addressed, negative effects on the clinical course were not confirmed.

Conclusions: The etiological relevance of A. radicidentis bacteremia in patients without specific infectious foci remains uncertain.

Background: Ceftriaxone-induced biliary pseudolithiasis is a disease entity frequently observed in children, while it is rarely seen in adult patients. We provide a thorough sonographic workup of the case to guide sonographers confronted with it.

Case report: A 41-years-old male patient with sonographically confirmed, culture-negative endocarditis accompanied by repeated fever episodes received 4g ceftriaxone per day next to ampicillin and gentamicin as an element of his antibiotic therapy. At day 4 of treatment, signs of gall bladder sludge and biliary pseudolithiasis were first seen in sonography. At day 17, abdominal pain over 30 min and increased liver and pancreatic enzymes pointed towards temporal duct obstruction as a complication and ceftriaxone therapy had to be preterm cancelled. A sonographic work-up of the stepwise improvement of the sonographic findings after the end of the ceftriaxone therapy is provided, a reemergence of endocarditis was not observed.

Discussion: The case reminds of a rarely recognized, usually reversible side effect of high-dose ceftriaxone therapy and its complications. The sonographic work-up may serve as guidance for clinicians during follow-up assessments.

Conclusions: Although ceftriaxone allows usually well-tolerated antimicrobial therapies, biliary pseudolithiasis should be kept in mind as a rare but sometimes non-ignorable side effect.

Introduction: The study was conducted to assess the effects of limescale deposits on faucet aerators on the qualitative and quantitative detection of microorganisms from swabbing and first jet water samples.

Methods: Limescale deposits on faucet aerators were categorized into three groups: not / slightly calcified, moderately calcified and heavily calcified. Colonization was assessed by isolating microorganisms from standardized swabbing and water samples. Microorganisms isolated from the aerators were compared with clinical isolates from the same year.

Results: Regardless of the degree of calcification on the faucet aerators, similar numbers and types of microorganisms were found. Except for Staphylococcus epidermidis and the rare occurrence of Staphylococcus aureus and Nacaseomyces glabratus on the aerators, there were no matches between the microorganisms isolated from the aerators and the top ten clinical isolates. Microorganisms frequently isolated from aerators, such as Sphingomonas paucimobilis, were extremely rare in clinical samples. No differences in species were observed based on the degree of calcification of the aerators.

Conclusions: The study did not demonstrate a significant effect of the degree of calcification on the colonization of aerators. Although calcification of aerators as a risk factor for increased microbial transmission cannot be entirely dismissed, its importance appears to be secondary.

Background: Interactions of helminth infections and human immunodeficiency virus (HIV) remain incompletely understood. This study aimed to assess the clinical, epidemiological, and immunological characteristics of co-infections involving HIV and selected nematode, trematode and cestode species commonly detected in stool samples.

Methods: A cross-sectional study was conducted among people-living-with-HIV (PLWH) with and without anti-retroviral therapy and HIV-negative controls at a tertiary hospital in Kumasi, Ghana. Stool samples were analyzed by real-time PCR for the presence of Strongyloides stercoralis, Schistosoma spp. as well as Taenia spp. Diagnostic findings were compared with clinical, demographic, socioeconomic and immunological data.

Results: Low prevalences of helminth infections were observed across the study population, ranging from 1.9% for S. stercoralis to 2.8% for Schistosoma spp. Only weak and infrequent associations were found between helminth infections and HIV status or immunosuppression. Identified risk factors included male sex, younger age, shorter duration since HIV diagnosis, and poor food hygiene in the case of taeniasis.

Conclusions: In this Ghanaian population, co-infections of HIV and helminths were infrequent and showed limited immunological associations. These findings suggest that helminth detection in PLWH is more likely to reflect local endemicity than HIV-related immunosuppression.

Bacterial pathogens, particularly antibiotic-resistant strains may constitute major challenges for the successful treatment of infected patients. Therefore, novel antibiotics or alternative, antibiotics-independent compounds with antimicrobial properties such as phytonutrients are needed. Our systematic literature review summarizes current knowledge on antibacterial effects of sulforaphane (SFN) in vitro and in vivo, including human studies. The isothiocyanate SFN is abundant in plants from the Brassicaceae family including broccoli. The 28 reports reviewed herein revealed that SFN i.) exerted antimicrobial effects against a variety of Gram-positive and Gram-negative bacteria; ii.) counteracted distinct virulence factors such as biofilm formation and toxin production (e.g. Shiga toxin); iii.) enhanced antibacterial immune cell responses mounting in anti-oxidant and anti-inflammatory actions thereby supporting bacterial killing and dampening inflammatory cell and tissue damage; iv.) prevented from aspirin-induced small intestinal cell injury; and v.) alleviated Helicobacter pylori-induced gastritis. In conclusion, given its antibacterial, immune-modulatory, and disease-alleviating effects, SFN constitutes a promising alternative antibiotic-independent candidate for the treatment of bacterial infections, warranting further consideration in clinical trials.