The Francisella tularensis-containing phagosome (FCP) matures to a late-endosome-like phagosome prior to bacterial escape into the cytosols of macrophages, where bacterial proliferation occurs. Our data show that within the first 15 min after infection of primary human monocyte-derived macrophages (hMDMs), ϳ90% of the FCPs acquire the proton vacuolar ATPase (vATPase) pump and the lysomotropic dye LysoTracker, which concentrates in acidic compartments, similar to phagosomes harboring the Listeria monocytogenes control. The acquired proton vATPase pump and lysomotropic dye are gradually lost by 30 to 60 min postinfection, which coincides with bacterial escape into the cytosols of hMDMs. Colocalization of phagosomes harboring the iglD mutant with the vATPase pump and the LysoTracker dye was also transient, and the loss of colocalization was faster than that observed for the wild-type strain, which is consistent with the faster escape of the iglD mutant into the macrophage cytosol. In contrast, colocalization of both makers with phagosomes harboring the iglC mutant was persistent, which is consistent with fusion to the lysosomes and failure of the iglC mutant to escape into the macrophage cytosol. We have utilized a fluorescence microscopy-based phagosome integrity assay for differential labeling of vacuolar versus cytosolic bacteria, using antibacterial antibodies loaded into the cytosols of live hMDMs. We show that specific inhibition of the proton vATPase pump by bafilomycin A1 (BFA) blocks rapid bacterial escape into the cytosols of hMDMs, but 30% to 50% of the bacteria escape into the cytosol by 6 to 12 h after BFA treatment. The effect of BFA on the blocking of bacterial escape into the cytosol is completely reversible, as the bacteria escape after removal of BFA. We also show that the limited fusion of the FCP to lysosomes is not due to failure to recruit the late-endosomal fusion regulator Rab7. Therefore, within few minutes of its biogenesis, the FCP transiently acquires the proton vATPase pump to acidify the phagosome, and this transient acidification is essential for subsequent bacterial escape into the macrophage cytosol.

Pseudomonas aeruginosa is an opportunistic pathogen, one of the leading causes of nosocomial infections such as pneumonia, urinary tract infections, and bacteraemia. The bacterial resistance to structurally unrelated antibiotics and its spread within hospitals limits the efficient antimicrobial options and patients' outcome. Carbapenems are important agents for the therapy of infections due to multidrug-resistant (MDR) P. aeruginosa; hence, the development of carbapenem resistance severely hampers effective therapeutic options. The aim of this investigation was to examine mechanisms of carbapenem resistance and genomic diversity in carbapenem-resistant MDR strains of P. aeruginosa, which caused an outbreak among patients in Clinical Hospital Rijeka. Most of the isolates showed decreased expression of porin that is important for the entry of carbapenems (oprD). Overexpression of MexAB-OprM, MexCD-OprJ, and MexEF-OprN efflux systems was observed in many of the isolates. Production of metallo-β-lactamases was not detected. Typing by pulsed-field gel electrophoresis discriminated the isolates into five clusters. The clonal distribution of the strains was related to the location of hospital departments where the isolates were collected, which implies that most of the infections were caused by spread of the epidemic strains within the hospital.

Background We aimed to determine if there was a higher incidence of small intestinal bacterial overgrowth (SIBO) in non‐alcoholic fatty liver disease (NAFLD) than in patients without NAFLD. Moreover, we assessed whether patients with significant fibrosis (SF) had a higher incidence of SIBO compared with patients with non‐significant or no liver fibrosis. Methods NAFLD was diagnosed in 117 patients by using Fibroscan with a controlled attenuation parameter (CAP) as well as liver biopsy (LB). SIBO was defined by esophagogastroduodenoscopy with an aspiration of the descending duodenum. Results Patients with non‐alcoholic steatohepatitis (NASH) and those with SF on LB had a significantly higher incidence of SIBO than patients without NASH and those without SF, respectively (P < .05). According to histological characteristics, there was a higher proportion of patients in the SIBO group with higher steatosis and fibrosis grade, lobular and portal inflammation, and ballooning grade (P < .001). In multivariate analysis, significant predictors associated with SF and NASH were type 2 diabetes mellitus (T2DM) and SIBO. Moreover, in multivariate analysis, significant predictors that were independently associated with SIBO were T2DM, fibrosis stage and ballooning grade (OR 8.80 (2.07‐37.37), 2.50 (1.16‐5.37) and 27.6 (6.41‐119), respectively). The most commonly isolated were gram‐negative bacteria, predominantly Escherichia coli and Klebsiella pneumoniae. Conclusion In this relatively large population of patients, we used a gold standard for both SIBO (quantitative culture of duodenum's descending part aspirate) and NAFLD (LB), and we demonstrated that NASH patients and those with SF had a higher incidence of SIBO. Moreover, significant predictors independently associated with SIBO were T2DM, fibrosis stage and ballooning grade. Although TE is a well‐investigated method for steatosis and fibrosis detection, in our study, independent predictors of SIBO were histological characteristics of NAFLD, while elastographic parameters did not reach statistical significance.

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Sažetak. Rezistencija na antimikrobne lijekove ugrožava kvalitetu medicinske skrbi u zajednici i bolničkom okruženju. Bakterijska rezistencija prisutna je od samog početka antibiotskog doba, ali je u proteklih dvadesetak godina poprimila zabrinjavajući trend porasta. Prirođena rezistencija je stalna, genetski zadana osobina nekog mikroorganizma. Stečena rezistencija nastaje neočekivano, u prethodno osjetljivoj bakteriji, mutacijom ili češće horizontalnim prijenosom gena putem plazmida. Rezistencija često nije u potpunosti genetski određena, već može biti heterogena unutar populacije, ovisna o okolišu, strukturi bakterijske populacije ili o fiziološkom stanju bakterijske stanice. Selekcijski pritisak antibiotika važan je čimbenik u odabiru i širenju rezistentnih bakterija. Pojava višestrukorezistentnih bakterija kao uzročnika bolesti posebno je alarmantna. Takvi mikroorganizmi uobičajeno se nazivaju "superbakterije", ali ne zato što su virulentnije, nego zato jer zbog suženog izbora antibiotika konačni ishod liječenja takvih infekcija može biti neizvjestan i često nepovoljan. Stoga je cilj ovog preglednog članka prikazati saznanja o rezistenciji, mehanizmima bakterijske otpornosti prema antibioticima i onim višestrukorezistentnim bakterijama koje danas predstavljaju najveću prijetnju globalno i lokalno, a udružene su pod akronimom ESKAPE.Abstract. Resistance to antimicrobial drugs jeopardizes the quality of medical care in the community and in the hospital environment. Bacterial resistance has been present since the beginning of the antibiotic period, but over the last twenty years it has a worrying increasing trend. Innate resistance is a permanent, genetic predetermined feature of some microorganism. Acquired resistance occurs unexpectedly, in a previously sensitive bacterium, by mutation, or more often by horizontal genes transmission by plasmids. Resistance does not always have to be completely genetically defined, but can be heterogeneous within the population, depending on the environment, bacterial population structure and physiological state of bacterial cell. Antibiotic selection pressure is an important factor in the selection and spread of resistant bacteria. Appearance of multiple resistant bacteria as a cause of the disease is particularly alarming. Such microorganisms, are commonly referred to as "superbacteria", not because they are more virulent, but due to the narrowed choice of susceptible antibiotics. The final outcomes of infections caused by these microorganisms are uncertain and often disadvantageous. Therefore, the aim of this review article is to provide insights into bacterial resistance, resistance mechanisms to antibiotics and multi-resistant bacteria that present the greatest threat globally and locally, and are associated under the acronym ESKAPE.

Objectives To assess the quality of antimicrobial prescribing and the level of adherence to the guidelines in the department of medicine at a university hospital. Methods A point prevalence survey was conducted between September 2008 and May 2011 at four selected time points. Demographic and relevant clinical patient data for those receiving antibiotic treatment were recorded. The necessity of antimicrobial treatment was assessed according to a scoring system based on the presence of signs and symptoms of an infection. Antibiotic use was judged according to Guidelines for hospital antimicrobial drug use published in December 2008. Results The percentage of patients receiving antimicrobials varied from 30.8% (N=73) (September 2008) to 25.1% (N=60) (May 2011). At the first time point, 37.3% (N=25) of patients received antimicrobial therapy that was not necessary significantly more often than at other time points (p<0.01). Level of adherence to the guidelines varied between 35.0% (April 2009) and 50.0% (May 2011). The highest level of non-compliance with the guidelines was observed when cefuroxime, ceftriaxone and ciprofloxacin were prescribed. Conclusions Our study demonstrates a continuous overuse of broad-spectrum antibiotics. A decrease in unnecessary antibiotic use and an increase in treatments based on susceptibility testing were noted in the periods when the guidelines were in use. This speaks in favour of guidelines for antimicrobial treatment being a valuable part of antimicrobial stewardship programmes.

Transplantirani i ostali urološki pacijenti imaju češće potrebu za uvođenjem ureteralnog stenta, odnosno urinarnih katetera, te su izloženi povećanom riziku za stjecanje infekcija mokraćnog sustava (IMS). To je najčešća infektivna komplikacija u primatelja alogeničnog grafta, glavni izvor pijelonefritisa, bakterijemije i sepse. Također, IMS su najzastupljenije infekcije povezane sa zdravstvenom skrbi, a glavni rizični čimbenik za njihov nastanak je upravo prisustvo katetera. Vodeći uzročnici ovih infekcija su E. coli, E. faecalis, vrste iz roda Klebsiella, Proteus i Pseudomonas koje često karakterizira i višestruka antimikrobna rezistencija, što dodatno ugrožava klinički ishod. Radi praćenja IMS-a povezanih s uporabom katetera svake se godine provodi jednodnevno presječno istraživanje kojim su obuhvaćeni svi pacijenti hospitalizirani taj dan. Rezultati pridonose sagledavanju problema, unaprjeđenju mjera prevencije, planiranju empirijske antimikrobne terapije, odnosno sigurnosti hospitaliziranih uroloških pacijenata.

Biological therapy of inflammatory bowel disease (IBD) carries an increased risk for the development of opportunistic infections due to immunomodulation. The aim of this study was to determine the prevalence and types of oral infections in IBD patients treated with biological (anti-TNF-α and anti-integrin-α4β7) and conventional medication protocols. The study included 20 IBD patients receiving anti-TNF-α therapy, 20 IBD patients receiving anti-integrin-α4β7 therapy and 20 IBD patients without immunomodulatory therapy. Participants completed questionnaires on medical information, oral lesions and symptoms. For each patient, clinical examination and a salivary flow rate test were performed, followed by a swab of the oral mucosa. The swab samples were cultured to identify Candida spp. and oral bacteria. No bacterial opportunistic infections were detected. Candidiasis was detected in four participants, with no significant difference between groups (p = 0.765). Hyposalivation was most common in the anti-TNF-α group, with a significant difference between groups (p = 0.036). There were no significant differences between groups in self-reported oral mucosal lesions and symptoms (p > 0.05), or in the distribution of oral mucosal lesions (p > 0.05). This study suggests that IBD patients receiving biological therapy are at no greater risk of developing oral opportunistic infections than IBD patients not receiving immunomodulatory therapy.