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Nature Reviews. Microbiology May 2015Urinary tract infections (UTIs) are a severe public health problem and are caused by a range of pathogens, but most commonly by Escherichia coli, Klebsiella pneumoniae,... (Review)
Review
Urinary tract infections (UTIs) are a severe public health problem and are caused by a range of pathogens, but most commonly by Escherichia coli, Klebsiella pneumoniae, Proteus mirabilis, Enterococcus faecalis and Staphylococcus saprophyticus. High recurrence rates and increasing antimicrobial resistance among uropathogens threaten to greatly increase the economic burden of these infections. In this Review, we discuss how basic science studies are elucidating the molecular details of the crosstalk that occurs at the host-pathogen interface, as well as the consequences of these interactions for the pathophysiology of UTIs. We also describe current efforts to translate this knowledge into new clinical treatments for UTIs.
Topics: Anti-Bacterial Agents; Bacterial Infections; Humans; Risk Factors; Urinary Tract Infections
PubMed: 25853778
DOI: 10.1038/nrmicro3432 -
Clinical Microbiology Reviews Oct 2014The definition of the heterogeneous group of coagulase-negative staphylococci (CoNS) is still based on diagnostic procedures that fulfill the clinical need to... (Review)
Review
The definition of the heterogeneous group of coagulase-negative staphylococci (CoNS) is still based on diagnostic procedures that fulfill the clinical need to differentiate between Staphylococcus aureus and those staphylococci classified historically as being less or nonpathogenic. Due to patient- and procedure-related changes, CoNS now represent one of the major nosocomial pathogens, with S. epidermidis and S. haemolyticus being the most significant species. They account substantially for foreign body-related infections and infections in preterm newborns. While S. saprophyticus has been associated with acute urethritis, S. lugdunensis has a unique status, in some aspects resembling S. aureus in causing infectious endocarditis. In addition to CoNS found as food-associated saprophytes, many other CoNS species colonize the skin and mucous membranes of humans and animals and are less frequently involved in clinically manifested infections. This blurred gradation in terms of pathogenicity is reflected by species- and strain-specific virulence factors and the development of different host-defending strategies. Clearly, CoNS possess fewer virulence properties than S. aureus, with a respectively different disease spectrum. In this regard, host susceptibility is much more important. Therapeutically, CoNS are challenging due to the large proportion of methicillin-resistant strains and increasing numbers of isolates with less susceptibility to glycopeptides.
Topics: Coagulase; Disease Management; Drug Resistance, Bacterial; Humans; Microbial Sensitivity Tests; Staphylococcal Infections; Staphylococcus
PubMed: 25278577
DOI: 10.1128/CMR.00109-13 -
International Journal of Molecular... Mar 2019Coagulase-negative Staphylococci (CoNS) are skin commensal bacteria. Besides their role in maintaining homeostasis, CoNS have emerged as major pathogens in nosocomial... (Review)
Review
Coagulase-negative Staphylococci (CoNS) are skin commensal bacteria. Besides their role in maintaining homeostasis, CoNS have emerged as major pathogens in nosocomial settings. Several studies have investigated the molecular basis for this emergence and identified multiple putative virulence factors with regards to pathogenicity. In the last decade, numerous CoNS whole-genome sequences have been released, leading to the identification of numerous putative virulence factors. Koch's postulates and the molecular rendition of these postulates, established by Stanley Falkow in 1988, do not explain the microbial pathogenicity of CoNS. However, whole-genome sequence data has shed new light on CoNS pathogenicity. In this review, we analyzed the contribution of genomics in defining CoNS virulence, focusing on the most frequent and pathogenic CoNS species: , , , and .
Topics: Coagulase; Genome, Bacterial; Genomics; Humans; Phylogeny; Staphylococcal Infections; Staphylococcus; Virulence; Virulence Factors
PubMed: 30862021
DOI: 10.3390/ijms20051215 -
International Journal of Molecular... Jun 2023Urinary tract infections (UTIs) are common bacterial infections that represent a severe public health problem. They are often caused by (), (), (), (), and ().... (Review)
Review
Urinary tract infections (UTIs) are common bacterial infections that represent a severe public health problem. They are often caused by (), (), (), (), and (). Among these, uropathogenic (UPEC) are the most common causative agent in both uncomplicated and complicated UTIs. The adaptive evolution of UPEC has been observed in several ways, including changes in colonization, attachment, invasion, and intracellular replication to invade the urothelium and survive intracellularly. While antibiotic therapy has historically been very successful in controlling UTIs, high recurrence rates and increasing antimicrobial resistance among uropathogens threaten to greatly reduce the efficacy of these treatments. Furthermore, the gradual global emergence of multidrug-resistant UPEC has highlighted the need to further explore its pathogenesis and seek alternative therapeutic and preventative strategies. Therefore, a thorough understanding of the clinical status and pathogenesis of UTIs and the advantages and disadvantages of antibiotics as a conventional treatment option could spark a surge in the search for alternative treatment options, especially vaccines and medicinal plants. Such options targeting multiple pathogenic mechanisms of UPEC are expected to be a focus of UTI management in the future to help combat antibiotic resistance.
Topics: Humans; Uropathogenic Escherichia coli; Escherichia coli Infections; Urinary Tract Infections; Anti-Bacterial Agents; Bacterial Infections; Urinary Tract
PubMed: 37445714
DOI: 10.3390/ijms241310537 -
Microbiology Spectrum Apr 2016Gram-positive bacteria are a common cause of urinary-tract infection (UTI), particularly among individuals who are elderly, pregnant, or who have other risk factors for... (Review)
Review
Gram-positive bacteria are a common cause of urinary-tract infection (UTI), particularly among individuals who are elderly, pregnant, or who have other risk factors for UTI. Here we review the epidemiology, virulence mechanisms, and host response to the most frequently isolated Gram-positive uropathogens: Staphylococcus saprophyticus, Enterococcus faecalis, and Streptococcus agalactiae. We also review several emerging, rare, misclassified, and otherwise underreported Gram-positive pathogens of the urinary tract including Aerococcus, Corynebacterium, Actinobaculum, and Gardnerella. The literature strongly suggests that urologic diseases involving Gram-positive bacteria may be easily overlooked due to limited culture-based assays typically utilized for urine in hospital microbiology laboratories. Some UTIs are polymicrobial in nature, often involving one or more Gram-positive bacteria. We herein review the risk factors and recent evidence for mechanisms of bacterial synergy in experimental models of polymicrobial UTI. Recent experimental data has demonstrated that, despite being cleared quickly from the bladder, some Gram-positive bacteria can impact pathogenic outcomes of co-infecting organisms. When taken together, the available evidence argues that Gram-positive bacteria are important uropathogens in their own right, but that some can be easily overlooked because they are missed by routine diagnostic methods. Finally, a growing body of evidence demonstrates that a surprising variety of fastidious Gram-positive bacteria may either reside in or be regularly exposed to the urinary tract and further suggests that their presence is widespread among women, as well as men. Experimental studies in this area are needed; however, there is a growing appreciation that the composition of bacteria found in the bladder could be a potentially important determinant in urologic disease, including susceptibility to UTI.
Topics: Animals; Bacteriuria; Gram-Positive Bacteria; Gram-Positive Bacterial Infections; Humans; Microbiota; Urinary Tract; Urinary Tract Infections
PubMed: 27227294
DOI: 10.1128/microbiolspec.UTI-0012-2012 -
Vaccines Jul 2022Staphylococcus saprophyticus is a Gram-positive coccus responsible for the occurrence of cystitis in sexually active, young females. While effective antibiotics against...
Staphylococcus saprophyticus is a Gram-positive coccus responsible for the occurrence of cystitis in sexually active, young females. While effective antibiotics against this organism exist, resistant strains are on the rise. Therefore, prevention via vaccines appears to be a viable solution to address this problem. In comparison to traditional techniques of vaccine design, computationally aided vaccine development demonstrates marked specificity, efficiency, stability, and safety. In the present study, a novel, multi-epitope vaccine construct was developed against S. saprophyticus by targeting fully sequenced proteomes of its five different strains, which were examined using a pangenome and subtractive proteomic strategy to characterize prospective vaccination targets. The three immunogenic vaccine targets which were utilized to map the probable immune epitopes were verified by annotating the entire proteome. The predicted epitopes were further screened on the basis of antigenicity, allergenicity, water solubility, toxicity, virulence, and binding affinity towards the DRB*0101 allele, resulting in 11 potential epitopes, i.e., DLKKQKEKL, NKDLKKQKE, QDKLKDKSD, NVMDNKDLE, TSGTPDSQA, NANSDGSSS, GSDSSSSNN, DSSSSNNDS, DSSSSDRNN, SSSDRNNGD, and SSDDKSKDS. All these epitopes have the efficacy to cover 99.74% of populations globally. Finally, shortlisted epitopes were joined together with linkers and three different adjuvants to find the most stable and immunogenic vaccine construct. The top-ranked vaccine construct was further scrutinized on the basis of its physicochemical characterization and immunological profile. The non-allergenic and antigenic features of modeled vaccine constructs were initially validated and then subjected to docking with immune receptor major histocompatibility complex I and II (MHC-I and II), resulting in strong contact. In silico cloning validations yielded a codon adaptation index (CAI) value of 1 and an ideal percentage of GC contents (46.717%), indicating a putative expression of the vaccine in E. coli. Furthermore, immune simulation demonstrated that, after injecting the proposed MEVC, powerful antibodies were produced, resulting in the sharpest peaks of IgM + IgG formation (>11,500) within 5 to 15 days. Experimental testing against S. saprophyticus can evaluate the safety and efficacy of these prophylactic vaccination designs.
PubMed: 36016080
DOI: 10.3390/vaccines10081192 -
Acta Medica Indonesiana Jan 2022Urease is an enzyme produced by diverse bacterial species including normal flora, non pathogens, and pathogens such as Proteus mirabilis, Staphylococcus saprophyticus,...
Urease is an enzyme produced by diverse bacterial species including normal flora, non pathogens, and pathogens such as Proteus mirabilis, Staphylococcus saprophyticus, Klebsiella pneumonia, Citrobacter freundii, Enterobacter cloacae Helicobacter spp and Helicobacter pylori. Urease is central in Helicobacter pylori metabolism and virulence, important for colonization in the gastric mucosa. Urease catalyzes the hydrolysis of urea to ammonia and carbamate. This ammonia product can be examined by Urease biopsy test and Urea breath test such as 14C-Urea Breath Test or 13C-Urea Breath Test.Previously, the Urea breath test was intended to detect an increase in ammonia which is a urease product in the gastric mucosa produced by pathogenic gastric bacteria, such as Helicobacter pylori, etc.Acute and chronic gastritis caused by infection with these pathogenic bacteria infection turned out to be positive on Urea breath test. Indirectly, the results of the urea breath test are also related to the presence of inflammation in acute and chronic gastritis, regardless of whether the cause is Helicobacter pylori or other urease-producing pathogenic bacteria.The use of the urea breath test indirectly in diagnosing acute and chronic gastritis should be studied further. The use of the urea breath test is indeed very important to assist health services in countries and regions with limited endoscopic facilities, especially developing countries.We know that the prevalence of Helicobacter pylori infection in causing acute and chronic gastritis by examination of Urea breath test in Indonesia is not too high, ranging from 2-11.2%. So that is why more studies on non-Helicobacter pylori producing urease pathogens are needed, which can appear as a false positive urea breath test.
Topics: Ammonia; Gastritis; Helicobacter Infections; Helicobacter pylori; Humans; Urea; Urease
PubMed: 35398819
DOI: No ID Found -
International Journal of Infectious... Dec 2017Staphylococcus saprophyticus is resistant to the drugs most often used for the empirical treatment of urinary tract infections (UTI). The adequacy of antimicrobial...
BACKGROUND
Staphylococcus saprophyticus is resistant to the drugs most often used for the empirical treatment of urinary tract infections (UTI). The adequacy of antimicrobial treatments prescribed for UTI due to S. saprophyticus is not usually questioned. This study described the epidemiology of such infections and assessed the susceptibility of S. saprophyticus to ceftriaxone and amoxicillin-clavulanic acid.
METHODS
Methicillin-susceptible S. saprophyticus (MSSS) isolated from clinical samples between November 2014 and July 2016 were included. Clinical data were recorded. The minimum inhibitory concentrations (MICs) of amoxicillin-clavulanic acid and ceftriaxone were measured for these MSSS strains and for 17 randomly selected methicillin-susceptible Staphylococcus aureus (MSSA) strains.
RESULTS
Of the S. saprophyticus isolates from urine, 59.5% were associated with a diagnosis of cystitis and 33.3% with pyelonephritis. Sixty percent of S. saprophyticus cystitis cases and 25% of pyelonephritis cases were given an inappropriate antibiotic regimen. The MICs of ceftriaxone ranged from 4 to >32μg/ml for MSSS, and from 1.5 to 4μg/ml for MSSA.
CONCLUSIONS
Many UTIs were treated with an empirical antibiotic therapy that was ineffective for S. saprophyticus, revealing that S. saprophyticus is an aetiology that is insufficiently considered in UTI. High MICs for ceftriaxone in MSSS were observed, which raises questions about the use of this antibiotic in UTIs due to S. saprophyticus.
Topics: Adolescent; Adult; Amoxicillin-Potassium Clavulanate Combination; Anti-Bacterial Agents; Ceftriaxone; Cystitis; Drug Resistance, Multiple, Bacterial; Empirical Research; Female; Humans; Male; Methicillin-Resistant Staphylococcus aureus; Microbial Sensitivity Tests; Pyelonephritis; Staphylococcus saprophyticus; Urinary Tract Infections; Young Adult; beta-Lactams
PubMed: 29030135
DOI: 10.1016/j.ijid.2017.10.001