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1.
World J Microbiol Biotechnol ; 40(11): 333, 2024 Oct 03.
Article in English | MEDLINE | ID: mdl-39358646

ABSTRACT

The Staphylococcus genus comprises multiple pathogenic and opportunistic species that represent a risk to public health. Epidemiological studies require accurate taxonomic classification of isolates with enough resolution to distinguish clonal complexes. Unfortunately, 16 S rRNA molecular analysis and phenotypic characterization cannot distinguish all species and do not offer enough resolution to assess intraspecific diversity. Other approaches, such as Multilocus Sequence Tagging, provide higher resolution; however, they have been developed for Staphylococcus aureus and a few other species. Here, we developed a set of genus-targeted primers using five orthologous genes (pta, tuf, tpi, groEs, and sarA) to identify all Staphylococcus species within the genus. The primers were initially evaluated using 20 strains from the Collection of Microorganisms of Interest in Animal Health from AGROSAVIA (CMISA), and their amplified sequences were compared to a set of 33 Staphylococcus species. This allowed the taxonomic identification of the strains even on close species and the establishment of intraspecies diversity. To enhance the scope and cost-effectiveness of the proposed strategy, we customized the primer sets for an Illumina paired-end amplicon protocol, enabling gene multiplexing. We assessed five genes across 177 strains, generating 880 paired-end libraries from the CMISA. This approach significantly reduced sequencing costs, as all libraries can be efficiently sequenced in a single MiSeq run at a fraction (one-fourth or less) of the cost associated with Sanger sequencing. In summary, this method can be used for precise identification and diversity analysis of Staphylococcus species, offering an advancement over traditional techniques in both resolution and cost-effectiveness.


Subject(s)
Coagulase , DNA, Bacterial , RNA, Ribosomal, 16S , Staphylococcus , Staphylococcus/genetics , Staphylococcus/classification , Staphylococcus/isolation & purification , Staphylococcus/enzymology , Coagulase/metabolism , Coagulase/genetics , RNA, Ribosomal, 16S/genetics , DNA, Bacterial/genetics , DNA Primers/genetics , Phylogeny , Staphylococcal Infections/microbiology , Animals , Genes, Bacterial/genetics , Bacterial Proteins/genetics , Sequence Analysis, DNA , Multilocus Sequence Typing , Bacterial Typing Techniques/methods , Genetic Markers , High-Throughput Nucleotide Sequencing
2.
PLoS One ; 19(10): e0309711, 2024.
Article in English | MEDLINE | ID: mdl-39361625

ABSTRACT

Methicillin-resistant Staphylococci (MRS) cause infections at various sites and exhibit multidrug resistance. Despite their importance in veterinary medicine, only little is known about Staphylococcus spp. colonizing and infecting cats. Therefore, in this study, we aimed to isolate and identify Staphylococcus spp. colonizing hospitalized and non-hospitalized domestic cats and analyze their antimicrobial resistance profiles, genetic diversity, and risk factors associated with MRS colonization. A total of 218 oral and axillary swabs were obtained from 109 cats, including 77 non-hospitalized and 32 hospitalized cats. After plating on selective media, the isolates were identified via matrix-assisted laser desorption/ionization time-of-flight mass spectrometry and rpoB and 16S rRNA gene sequencing. Subsequently, antimicrobial sensitivity of the strains was assessed, and they were screened for mecA gene. Methicillin-resistant S. haemolyticus (MRSH) isolates were subjected to multilocus sequence typing, whereas methicillin-resistant S. pseudintermedius (MRSP) and S. felis isolates were subjected to whole genome sequencing. S. felis was most commonly isolated from non-hospitalized cats (28.1%), whereas S. pseudintermedius and MRS were commonly isolated from hospitalized cats (25%). MRSH isolates from hospitalized animals were classified as ST3. The identified MRSP strains belonged to two well-known sequence types, ST551 and ST71. Moreover, antimicrobial use (p = 0.0001), hospitalization (p = 0.0141), and comorbidities (p = 0.002) were associated with increased MRS prevalence in cats.


Subject(s)
Cat Diseases , Genetic Variation , Staphylococcal Infections , Animals , Cats/microbiology , Staphylococcal Infections/microbiology , Staphylococcal Infections/veterinary , Staphylococcal Infections/epidemiology , Brazil , Cat Diseases/microbiology , Anti-Bacterial Agents/pharmacology , Staphylococcus/genetics , Staphylococcus/drug effects , Staphylococcus/isolation & purification , Methicillin-Resistant Staphylococcus aureus/genetics , Methicillin-Resistant Staphylococcus aureus/drug effects , Methicillin-Resistant Staphylococcus aureus/isolation & purification , Female , Microbial Sensitivity Tests , Male , RNA, Ribosomal, 16S/genetics , Methicillin Resistance/genetics , Hospitalization , Bacterial Proteins/genetics , Multilocus Sequence Typing
3.
J Med Microbiol ; 73(9)2024 Sep.
Article in English | MEDLINE | ID: mdl-39234813

ABSTRACT

Introduction. Staphylococcus aureus is a leading agent in community-acquired bacteraemia (CAB) and has been linked to elevated mortality rates and methicillin resistance in Costa Rica.Gap statement and aim. To update and enhance previous data obtained in this country, we analysed the clinical manifestations of 54 S. aureus CAB cases in a tertiary hospital and delineated the sequence types (STs), virulome, and resistome of the implicated isolates.Methodology. Clinical information was retrieved from patient files. Antibiotic susceptibility profiles were obtained with disc diffusion and automated phenotypic tests. Genomic data were exploited to type the isolates and for detection of resistance and virulence genes.Results. Primary infections predominantly manifested as bone and joint infections, followed by skin and soft tissue infections. Alarmingly, 70% of patients continued to exhibit positive haemocultures beyond 48 h of treatment modification, with nearly a quarter requiring mechanical ventilation or developing septic shock. The 30-day mortality rate reached an alarming 40%. More than 60% of the patients were found to have received suboptimal or inappropriate antibiotic treatment, and there was an alarming tendency towards the overuse of third-generation cephalosporins as empirical treatment. Laboratory tests indicated elevated creatinine levels, leukocytosis, and bandaemia within the first 24 h of hospitalization. However, most showed improvement after 48 h. The isolates were categorized into 13 STs, with a predominance of representatives from the clonal complexes CC72 (ST72), CC8 (ST8), CC5 (ST5, ST6), and CC1 (ST188). Twenty-four isolates tested positive for mecA, with ST72 strains accounting for 20. In addition, we detected genes conferring acquired resistance to aminoglycosides, MLSB antibiotics, trimethoprim/sulfamethoxazole, and mutations for fluoroquinolone resistance in the isolate collection. Genes associated with biofilm formation, capsule synthesis, and exotoxin production were prevalent, in contrast to the infrequent detection of enterotoxins or exfoliative toxin genes.Conclusions. Our findings broaden our understanding of S. aureus infections in a largely understudied region and can enhance patient management and treatment strategies.


Subject(s)
Anti-Bacterial Agents , Bacteremia , Community-Acquired Infections , Microbial Sensitivity Tests , Staphylococcal Infections , Staphylococcus aureus , Tertiary Care Centers , Humans , Costa Rica/epidemiology , Tertiary Care Centers/statistics & numerical data , Community-Acquired Infections/microbiology , Community-Acquired Infections/epidemiology , Community-Acquired Infections/mortality , Staphylococcal Infections/microbiology , Staphylococcal Infections/epidemiology , Staphylococcal Infections/drug therapy , Staphylococcal Infections/mortality , Bacteremia/microbiology , Bacteremia/epidemiology , Bacteremia/mortality , Bacteremia/drug therapy , Male , Staphylococcus aureus/genetics , Staphylococcus aureus/drug effects , Staphylococcus aureus/isolation & purification , Middle Aged , Female , Aged , Adult , Anti-Bacterial Agents/therapeutic use , Anti-Bacterial Agents/pharmacology , Aged, 80 and over , Young Adult , Adolescent , Virulence Factors/genetics , Child
4.
BMC Infect Dis ; 24(1): 1081, 2024 Sep 30.
Article in English | MEDLINE | ID: mdl-39350037

ABSTRACT

BACKGROUND: In the pediatric population, Staphylococcus aureus infections are responsible for increased morbidity and mortality, length of hospitalization and the cost of inpatient treatment. The aim of this study is to describe the antimicrobial resistance profile of S. aureus isolated in clinical specimens from pediatric patients admitted to a tertiary hospital in Rio de Janeiro, Brazil. METHODS: Culture reports and medical records of hospitalized patients under 18 years of age with S. aureus infections between January 2015 and December 2022 were retrospectively analyzed. Information was collected on recent antibiotic use, previous hospital admission, inpatient unit, clinical specimen, time of infection (community or nosocomial), classification according to susceptibility to methicillin (methicillin sensitive - MSSA or methicillin resistant - MRSA) and sensitivity to other antimicrobials. We analyzed the distribution of the sensitivity profile of S. aureus infections over the 7 years evaluated in the study. RESULTS: Were included 255 unique clinical episodes, among which the frequencies of MSSA and MRSA were 164 (64%) and 91 (36%), respectively. Over the 7 years evaluated, there was stability in the prevalence percentage, with a predominance of MSSA in the range of 60 to 73.3%, except in 2020, when there was a drop in the prevalence of MSSA (from 73.3% in 2019 to 52.5%) with an increase in MRSA (from 26.7% in 2019 to 47.5%). Ninety-seven (38%) infections were community-acquired and 158 (62%) were healthcare-associated. The main clinical specimens collected were blood cultures (35.2%) and wound secretions (17%). The MRSA isolates presented percentages of sensitivity to trimethoprim-sulfamethoxazole from 90.4 to 100%, and to clindamycin from 77 to 89.8% in MRSA healthcare associated and MRSA community respectively. CONCLUSION: There was a constant predominance in the prevalence of MSSA with percentage values ​​maintained from 2015 to 2022, except in 2020, in which there was a specific drop in the prevalence of MSSA with an increase in MRSA. MSSA infections are still predominant in the pediatric population, but MRSA rates also present significant values, including in community infections, and should be considered in initial empiric therapy.


Subject(s)
Anti-Bacterial Agents , Methicillin-Resistant Staphylococcus aureus , Microbial Sensitivity Tests , Staphylococcal Infections , Staphylococcus aureus , Tertiary Care Centers , Humans , Tertiary Care Centers/statistics & numerical data , Child , Brazil/epidemiology , Staphylococcal Infections/microbiology , Staphylococcal Infections/epidemiology , Staphylococcal Infections/drug therapy , Child, Preschool , Female , Male , Longitudinal Studies , Infant , Retrospective Studies , Staphylococcus aureus/drug effects , Staphylococcus aureus/isolation & purification , Adolescent , Anti-Bacterial Agents/pharmacology , Methicillin-Resistant Staphylococcus aureus/drug effects , Methicillin-Resistant Staphylococcus aureus/isolation & purification , Methicillin-Resistant Staphylococcus aureus/genetics , Cross Infection/microbiology , Cross Infection/epidemiology , Cross Infection/drug therapy , Prevalence , Infant, Newborn
5.
Microb Pathog ; 195: 106903, 2024 Oct.
Article in English | MEDLINE | ID: mdl-39208961

ABSTRACT

The emergence of highly successful genetic lineages of methicillin-resistant Staphylococcus aureus (MRSA) poses a challenge in human healthcare due to increased morbidity and mortality rates. The RdJ clone (CC5-ST105-SCCmecII-t002 lineage), previously identified in Rio de Janeiro, Brazil, was linked to bloodstream infections and features a mutation in the aur gene (encoding aureolysin). Additionally, clinical isolates derived from this clone were more effective at evading monocytic immune responses. This study aimed to detect the RdJ clone among clinical MRSA isolated in Santa Catarina (SC) and examine its antimicrobial resistance and phagocytosis evasion capabilities. Our findings revealed the RdJ clone in 20 % of MRSA isolates, all exhibiting multiresistance. RdJ clone isolates from SC did not demonstrate a decreased rate of phagocytosis compared to CC5 non-RdJ isolates. Structural analysis suggests that the aur mutation is unlikely to significantly impact aureolysin activity. Genomic analysis of one isolate unveiled a genetic variant of the RdJ clone, sharing lineage and gene distribution but lacking the aur mutation. This study enhances the understanding of the clinical and epidemiologic risks associated with the RdJ clone and the biological mechanisms underlying its spreading in SC.


Subject(s)
Methicillin-Resistant Staphylococcus aureus , Phagocytosis , Staphylococcal Infections , Brazil/epidemiology , Methicillin-Resistant Staphylococcus aureus/genetics , Methicillin-Resistant Staphylococcus aureus/isolation & purification , Staphylococcal Infections/microbiology , Staphylococcal Infections/epidemiology , Humans , Anti-Bacterial Agents/pharmacology , Microbial Sensitivity Tests , Mutation , Bacterial Proteins/genetics , Drug Resistance, Multiple, Bacterial/genetics
6.
Biomed Pharmacother ; 179: 117373, 2024 Oct.
Article in English | MEDLINE | ID: mdl-39208663

ABSTRACT

OBJECTIVE: Analyse the incidence, risk factors, antimicrobial susceptibility profile, and fatality in neonates infected with oxacillin-resistant Staphylococcus spp. (ORS). METHODS: In this retrospective observational descriptive cohort study, the medical records of neonates admitted to the Neonatal Intensive Care Unit (NICU) from January 2015 to June 2022 were analysed. Participants were monitored daily through the National Healthcare Safety Network. RESULTS: Among the 1610 neonates, 193 (12 %) developed ORS infections, primarily in the bloodstream (96.8 %). The incidence of these infections/patient-days decreased by 51.8 % between 2016 (8.3) and 2022 (4). The median age of affected neonates was 17.5 days (IQR:12-28.7). Pre-emptive prescription of fourth-generation cephalosporins (OR=14.36; P<0.01) emerged as a risk factor in the multivariate analysis. Staphylococcus epidermidis was the most prevalent species (60.1 %), with one isolate showing a "susceptible, increased exposure" profile to vancomycin. Additionally, 2 % of pathogens were extensively drug-resistant (XDR). ORS infections were associated with prolonged hospital stays (from 10 to 46 days) and increased mortality (from 10.2 % to 19.2 %). The median time between infection and the fatal outcome was 15 days (IQR:8-40), and Staphylococcus capitis was the most lethal species (26.7 %). CONCLUSIONS: The high incidence of ORS infections was linked to extended hospitalisation and increased mortality, highlighting the complexity of this situation - a "perfect storm." This underscores the urgency of implementing effective interventions for managing and preventing ORS infections in the NICU.


Subject(s)
Anti-Bacterial Agents , Intensive Care Units, Neonatal , Oxacillin , Staphylococcal Infections , Staphylococcus , Female , Humans , Infant, Newborn , Male , Anti-Bacterial Agents/therapeutic use , Brazil/epidemiology , Drug Resistance, Bacterial/drug effects , Incidence , Microbial Sensitivity Tests , Oxacillin/therapeutic use , Retrospective Studies , Risk Factors , Staphylococcal Infections/microbiology , Staphylococcal Infections/drug therapy , Staphylococcal Infections/mortality , Staphylococcal Infections/epidemiology , Staphylococcus/drug effects , Staphylococcus/isolation & purification
7.
Microb Pathog ; 195: 106863, 2024 Oct.
Article in English | MEDLINE | ID: mdl-39159772

ABSTRACT

Staphylococcus aureus is a bacterial pathogen that causes bloodstream infections, pneumonia, and skin abscesses and is the primary pathogen responsible for medical devices associated with biofilm infections, accounting for approximately 70 % of cases. Therefore, the World Health Organization (WHO) has designated this microorganism as a top priority due to its role in causing over 20,000 bacteremia-related deaths in the US each year. The issue of pathogen resistance to antibiotics, mainly by a biofilm, further complicates these infections since biofilms render the bacterial colony impervious to antibiotics. However, many natural and synthetic substances also induce bacterial biofilm formation. Therefore, we investigated whether the most common active pharmaceutical ingredients (APIs) could induce biofilm formation in two clinical isolates of extended-spectrum beta-lactamase Staphylococcus aureus, one of them also methicillin-resistant (A2M) and two medical devices. We detected biofilm inducers, inhibitors, and destabilizers. Microbial strain, medical devices, API structure, and concentration influenced the modulatory effects of biofilm. In all devices tested, including microplates, FR18 duodenal probe, and respiratory probe, the clinic isolate methicillin-resistant S. aureus A2M exhibited lower susceptibility to biofilm formation than S. aureus A1. The anti-inflammatory acetaminophen, the hypocholesterolemic lovastatin, and the diuretic hydrochlorothiazide all induced biofilm. However, verapamil, an antihypertensive, and cetirizine, an antihistamine, inhibited biofilm on S. aureus A2M, while propranolol, another antihypertensive, inhibited biofilm on S. aureus A1. Additionally, diclofenac, an analgesic, and cetirizine destabilized the biofilm, resulting in more free bacteria and possibly making them more susceptible to external agents such as antibiotics. Nonetheless, further epidemiologic analyses and in vivo assays are needed to confirm these findings and to establish a correlation between drug use, the onset of bacterial infections in patients, and the use of medical devices. This work provides information about the probable clinical implications of drugs in patients using medical devices or undergoing surgical procedures. Inhibitory APIs could also be used as drug repurposing or templates to design new, more potent biofilm inhibitors.


Subject(s)
Anti-Bacterial Agents , Biofilms , Microbial Sensitivity Tests , Staphylococcal Infections , Staphylococcus aureus , beta-Lactamases , Biofilms/drug effects , Biofilms/growth & development , Anti-Bacterial Agents/pharmacology , Humans , Staphylococcus aureus/drug effects , Staphylococcal Infections/microbiology , Staphylococcal Infections/drug therapy , beta-Lactamases/metabolism , Methicillin-Resistant Staphylococcus aureus/drug effects
8.
J Mol Graph Model ; 132: 108848, 2024 Nov.
Article in English | MEDLINE | ID: mdl-39182254

ABSTRACT

Staphylococcus aureus is a common bacterium that causes a variety of infections in humans. This microorganism produces several virulence factors, including hemolysins, which contribute to its disease-causing ability. The treatment of S. aureus infections typically involves the use of antibiotics. However, the emergence of antibiotic-resistant strains has become a major concern. Therefore, vaccination against S. aureus has gained attention as an alternative approach. Vaccination has the advantage of stimulating the immune system to produce specific antibodies that can neutralize bacteria and prevent infection. However, developing an effective vaccine against S. aureus has proven to be challenging. This study aimed to use in silico methods to design a multi-epitope vaccine against S. aureus infection based on hemolysin proteins. The designed vaccine contained four B-cell epitopes, four CTL epitopes, and four HTL epitopes, as well as the ribosomal protein L7/L12 and pan-HLA DR-binding epitope, included as adjuvants. Furthermore, the vaccine was non-allergenic and non-toxic with the potential to stimulate the TLR2-, TLR-4, and TLR-6 receptors. The predicted vaccine exhibited a high degree of antigenicity and stability, suggesting potential for further development as a viable vaccine candidate. The population coverage of the vaccine was 94.4 %, indicating potential widespread protection against S. aureus. Overall, these findings provide valuable insights into the design of an effective multi-epitope vaccine against S. aureus infection and pave the way for future experimental validations.


Subject(s)
Epitopes, B-Lymphocyte , Hemolysin Proteins , Staphylococcus aureus , Hemolysin Proteins/immunology , Hemolysin Proteins/chemistry , Staphylococcus aureus/immunology , Epitopes, B-Lymphocyte/immunology , Epitopes, B-Lymphocyte/chemistry , Humans , Staphylococcal Vaccines/immunology , Staphylococcal Vaccines/chemistry , Computational Biology/methods , Epitopes, T-Lymphocyte/immunology , Epitopes, T-Lymphocyte/chemistry , Staphylococcal Infections/immunology , Staphylococcal Infections/prevention & control , Molecular Docking Simulation , Epitopes/immunology , Epitopes/chemistry , Amino Acid Sequence
9.
J Bras Pneumol ; 50(4): e20240026, 2024.
Article in English | MEDLINE | ID: mdl-39194074

ABSTRACT

OBJECTIVE: Thymidine-dependent small-colony variants (TD-SCVs) of Staphylococcus aureus are being isolated with increasing frequency from patients with cystic fibrosis (CF). The aim of this study was to evaluate the relationship between TD-SCV isolation and pulmonary function in patients with CF, as well as to determine whether the emergence of TD-SCVs was associated with trimethoprim-sulfamethoxazole (TMP-SMX) use and with coinfection with other microorganisms. METHODS: This was a retrospective case-control study including patients with CF who visited the Clinical Hospital Complex of the Federal University of Paraná, in Curitiba, Brazil, between 2013 and 2022. Demographic, clinical, and spirometric data, as well as information on TD-SCVs and other isolated microorganisms, were collected from the medical records of patients with CF and TD-SCVs (TD-SCV group; n = 32) and compared with those of a matched group of patients with CF without TD-SCVs (control group; n = 64). RESULTS: Isolation of TD-SCVs was positively associated with TMP-SMX use (p = 0.009), hospitalization (p < 0.001), and impaired pulmonary function (p = 0.04). CONCLUSIONS: The use of TMP-SMX seems to contribute to the emergence of TD-SCVs, the isolation of which was directly associated with worse pulmonary function in our sample.


Subject(s)
Cystic Fibrosis , Staphylococcal Infections , Staphylococcus aureus , Humans , Cystic Fibrosis/microbiology , Cystic Fibrosis/physiopathology , Retrospective Studies , Male , Female , Case-Control Studies , Staphylococcus aureus/drug effects , Staphylococcal Infections/microbiology , Staphylococcal Infections/drug therapy , Staphylococcal Infections/physiopathology , Adult , Young Adult , Adolescent , Thymidine/analogs & derivatives , Trimethoprim, Sulfamethoxazole Drug Combination/therapeutic use , Trimethoprim, Sulfamethoxazole Drug Combination/pharmacology , Lung/physiopathology , Lung/microbiology , Lung/drug effects , Anti-Bacterial Agents/therapeutic use , Anti-Bacterial Agents/pharmacology , Child , Brazil , Respiratory Function Tests
10.
J Med Primatol ; 53(5): e12732, 2024 Oct.
Article in English | MEDLINE | ID: mdl-39160696

ABSTRACT

BACKGROUND: Marmosets (Callithrix sp.), including black-tuffed marmosets (C. penicillata), are neotropical primates that can be highly adapted to urban environments, especially parks and forested areas near cities. Staphylococcus spp. are part of the microbiota of many different hosts and lead to opportunistic severe infection. Isolates from wild animals can be resistant to antimicrobial drugs. However, there are a few studies that evaluated Staphylococcus spp. in neotropical primates. The goal of this study was to evaluate Staphylococcus spp. isolated from free-ranging black-tuffed marmosets. METHODS: Marmosets were captured in six urban parks. After sedation, skin and rectal swabs and feces were sampled. Staphylococcus spp. isolates were identified by MALDI-ToF and their antimicrobial susceptibility was determined. RESULTS: Over 30% of captured individuals were positive for Staphylococcus spp., and S. aureus was the most isolated species followed by Mammaliicoccus (Staphylococcus) sciuri. With the exception of the marmoset subjected to necropsy, none of the other had lesions, which supports that notion that Staphylococcus spp. are members of the microbiota, but also opportunistic pathogens. Most isolates were susceptible to all antimicrobials tested; however, one isolate of S. epidermidis was resistant to multiple antimicrobials (penicillin, cefoxitin, ciprofloxacin, clindamycin, and erythromycin). We considered S. aureus as the main staphylococci to colonize black-tuffed marmosets. CONCLUSIONS: Black-tuffed marmosets can be colonized by several Staphylococcus species, most frequently by S. aureus, and the majority of isolates were sensible to the antimicrobials tested. One S. epidermidis isolate was considered multidrug resistant.


Subject(s)
Anti-Bacterial Agents , Callithrix , Monkey Diseases , Staphylococcal Infections , Staphylococcus , Animals , Callithrix/microbiology , Staphylococcus/drug effects , Staphylococcus/isolation & purification , Monkey Diseases/microbiology , Monkey Diseases/epidemiology , Staphylococcal Infections/veterinary , Staphylococcal Infections/microbiology , Staphylococcal Infections/epidemiology , Anti-Bacterial Agents/pharmacology , Female , Drug Resistance, Bacterial , Male , Microbiota/drug effects , Cities , Brazil/epidemiology , Feces/microbiology
11.
Lett Appl Microbiol ; 77(8)2024 Aug 05.
Article in English | MEDLINE | ID: mdl-39127610

ABSTRACT

Staphylococcus aureus, particularly multi-drug resistant strains, presents significant challenges in dairy farming due to its role in causing bovine mastitis, which leads to substantial economic losses and limited treatment options. Seeking alternative therapies, we investigated the potential of a topical formulation derived from the medicinal herb Salvia officinalis to combat S. aureus growth and biofilms associated with bovine mastitis. Through systematic extraction in different solvents and fractionation by column chromatography, we isolated and identified three key multicyclic terpenoids-ferruginol, sugiol, and sclareol-exhibiting significant antimicrobial activity. The formulation effectively inhibited biofilm formation, with minimum inhibitory concentration (MIC) values ranging from 0.09 to 0.74 mg ml-1 against clinical S. aureus strains, comparable to or lower than those of the pure compounds. Moreover, it displayed robust anti-adhesive properties, reducing biofilm formation by 20%-79% at subinhibitory concentrations. Furthermore, the formulation successfully disrupted pre-existing biofilms, achieving reductions ranging from 30% to 82%. Cytotoxicity assays confirmed the safety of the formulation on mammary epithelial cells, with cell viability maintained at 100% at MIC. Our findings underscore the therapeutic potential of Sa. officinalis-derived compounds in managing bovine mastitis caused by S. aureus, emphasizing their antimicrobial efficacy and safety profile.


Subject(s)
Anti-Bacterial Agents , Biofilms , Mastitis, Bovine , Microbial Sensitivity Tests , Plant Extracts , Plants, Medicinal , Salvia officinalis , Staphylococcus aureus , Terpenes , Staphylococcus aureus/drug effects , Biofilms/drug effects , Animals , Cattle , Salvia officinalis/chemistry , Terpenes/pharmacology , Terpenes/chemistry , Terpenes/isolation & purification , Mastitis, Bovine/microbiology , Mastitis, Bovine/drug therapy , Plant Extracts/pharmacology , Plant Extracts/chemistry , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/isolation & purification , Anti-Bacterial Agents/chemistry , Plants, Medicinal/chemistry , Staphylococcal Infections/microbiology , Staphylococcal Infections/drug therapy , Female
12.
Eur J Pharm Biopharm ; 202: 114416, 2024 Sep.
Article in English | MEDLINE | ID: mdl-39013494

ABSTRACT

Owing to its exposed nature, the skin can be injured by various factors, including by Staphylococcus aureus, which inhabits its innate microbiota. Treatment of infected wounds presents an important challenge, making it imperative to develop new treatment options. Plant-derived formulations, such as those containing Melaleuca alternifolia essential oil (MaEO), are used for wound treatment because of their healing, anti-inflammatory, and antimicrobial properties. This study presents a cream containing 2% MaEO (2% CMa) and evaluates its effects in an S. aureus-infected wound murine model. The 2% CMa was subjected to quality control testing and pH and analysis of density, organoleptic characteristics, and microbiological effects. The quality control parameters all revealed the good stability of the 2% CMa. The formulation strongly reduced the S. aureus ATCC 6538 colony-forming unit (CFU) count in an ex vivo porcine skin model. In the murine model, daily topical application of 2% CMa reduced the severity and size of S. aureus-infected wounds and the bacterial load. These effects may be due to the presence of terpinen-4-ol, which exhibits anti-inflammatory activity. Based on these findings, the formulation exhibits good quality and safety. We suggest the topical application of this formulation, which exhibited an antimicrobial effect, as an interesting treatment strategy for wound healing.


Subject(s)
Melaleuca , Oils, Volatile , Staphylococcal Infections , Staphylococcus aureus , Wound Healing , Animals , Wound Healing/drug effects , Staphylococcus aureus/drug effects , Mice , Melaleuca/chemistry , Oils, Volatile/pharmacology , Oils, Volatile/administration & dosage , Swine , Staphylococcal Infections/drug therapy , Staphylococcal Infections/microbiology , Wound Infection/drug therapy , Wound Infection/microbiology , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/administration & dosage , Tea Tree Oil/pharmacology , Tea Tree Oil/administration & dosage , Tea Tree Oil/chemistry , Skin/drug effects , Skin/microbiology , Biological Products/pharmacology , Biological Products/administration & dosage , Biological Products/chemistry , Female , Disease Models, Animal , Male
13.
Braz J Microbiol ; 55(3): 2923-2936, 2024 Sep.
Article in English | MEDLINE | ID: mdl-38955982

ABSTRACT

Staphylococcus pseudintermedius, which is part of the skin microbiome of dogs, causes a variety of opportunistic infections. These infections may become more difficult to treat due to the formation of biofilm. The capacity of S. pseudintermedius to form biofilm, as well as the associated genes, has not been elucidated. This study evaluated the production and composition of S. pseudintermedius biofilm. Samples were collected from both infected dogs and asymptomatic dogs. Isolates were identified using mass spectrometry and Multiplex-PCR. Biofilm production and composition were assessed using a quantitative microtiter plate assay. The presence of ica operon genes and sps genes was investigated using conventional PCR. The investigation of Agr type and virulence genes was conducted in silico on 24 sequenced samples. All strains could produce strong biofilms, with most of the isolates presenting a polysaccharide biofilm. 63.6% of the isolates carried the complete ica operon (ADBC). All samples showed the presence of the genes spsK, spsA, and spsL, while the distribution of other genes varied. Agr type III was the most prevalent (52.2%). All sequenced samples carried the cytotoxins hlb, luk-S, luk-F, as well as the exfoliative toxins siet and se_int. No isolate displayed other exfoliative toxins. Only LB1733 presented a set of different enterotoxins (sea, seb, sec_canine, seh, sek, sel, and seq). Our findings suggest that S. pseudintermedius is a strong producer of biofilm and carries virulence genes.


Subject(s)
Biofilms , Dog Diseases , Staphylococcus , Animals , Biofilms/growth & development , Dogs , Dog Diseases/microbiology , Virulence/genetics , Staphylococcus/genetics , Staphylococcus/isolation & purification , Staphylococcus/pathogenicity , Staphylococcus/classification , Staphylococcus/physiology , Staphylococcal Infections/microbiology , Staphylococcal Infections/veterinary , Virulence Factors/genetics , Bacterial Proteins/genetics , Operon
14.
Lett Appl Microbiol ; 77(7)2024 Jul 01.
Article in English | MEDLINE | ID: mdl-38970380

ABSTRACT

Alternative strategies for controlling Staphylococcus aureus and other pathogens have been continuously investigated, with nisin, a bacteriocin widely used in the food industry as a biopreservative, gaining increasing attention. In addition to its antimicrobial properties, bacteriocins have significant effects on genome functionality even at inhibitory concentrations. This study investigated the impact of subinhibitory concentrations of nisin on S. aureus. Culturing in the presence of 0.625 µmol l-1 nisin, led to the increased relative expression of hla, saeR, and sarA, genes associated with virulence while expression of the sea gene, encoding staphylococcal enterotoxin A (SEA), decreased. In an in vivo experiment, Galleria mellonella larvae inoculated with S. aureus cultured in the presence of nisin exhibited 97% mortality at 72 h post-infection, compared to over 40% of larvae mortality in larvae infected with S. aureus. A comprehensive understanding of the effect of nisin on the transcriptional response of virulence genes and the impact of these changes on the virulence of S. aureus can contribute to assessing the application of this bacteriocin in food and medical contexts.


Subject(s)
Anti-Bacterial Agents , Larva , Moths , Nisin , Staphylococcus aureus , Nisin/pharmacology , Staphylococcus aureus/drug effects , Staphylococcus aureus/genetics , Staphylococcus aureus/pathogenicity , Animals , Virulence/genetics , Larva/microbiology , Larva/drug effects , Anti-Bacterial Agents/pharmacology , Moths/microbiology , Staphylococcal Infections/microbiology , Gene Expression Regulation, Bacterial/drug effects , Bacterial Proteins/genetics , Bacterial Proteins/metabolism , Virulence Factors/genetics , Microbial Sensitivity Tests
16.
Braz J Microbiol ; 55(3): 2705-2713, 2024 Sep.
Article in English | MEDLINE | ID: mdl-38896343

ABSTRACT

Staphylococcus aureus are extremely important microorganisms, either from an epidemiological point of view or as a pathogen, responsible for causing a series of infectious processes, whether simple, restricted to the skin, or invasive infections such as bacteremia. The emergence of Oxacillin Sensitive-Methicillin Resistant S.aureus (OS-MRSA) isolates has imposed difficulties in the treatment of patients with staphylococcal infection, as such isolates can be mistakenly classified as sensitive and lead to failure of the therapy used. Thus, the objective of this study is to evaluate the prevalence, and genotypic and phenotypic characteristics, of OS-MRSA isolates, from bloodstream infections, collected from patients admitted to a hospital in southern Brazil, as well as to evaluate the treatment used. For this, 801 unique isolates of S. aureus, collected from blood cultures, between January 2011 and December 2020 were evaluated. Of these, 96 isolates were classified as sensitive to oxacillin. The isolates were identified and had their sensitivity profile performed by manual and automated methods. The minimum inhibitory concentration for vancomycin, daptomycin, oxacillin, linezolid and teicoplanine was performed by e-test. The mecA, vanA genes, typing of the SCCmec elements, as well as the search for the icaA, tst-1 and pvl virulence genes were performed by PCR. Biofilm formation was performed using the crystal violet technique. The Sequence Type (ST), as well as the Clonal Complex (CC) of the isolates was evaluated by the RTq -PCR. The clinical characteristics of the patients were evaluated through an active search in medical records. After investigating the mecA gene, 27.1% (26/96) of the isolates were considered OS-MRSA, with SCCmec type I being the most prevalent, 46.1% (12/26). Among the evaluated isolates, 41% (9/22) were included in CC5 and ST9. As for virulence, all isolates were positive for the icaA gene and characterized as strong biofilm formers. The pvl gene was found in 92.3% (24/26) of the isolates and the toxic shock syndrome toxin was present in 61.5% of the isolates (16/26). All isolates were negative for the presence of the van A gene. As for the clinical outcome, 73% (19/26) of the patients were discharged from the hospital and 27% (7/26) died. It was possible to observe a high frequency of OS-MRSA isolates causing bloodstream infections. Furthermore, such isolates contain several virulence genes, which may contribute to a worse clinical outcome.


Subject(s)
Anti-Bacterial Agents , Bacteremia , Bacterial Proteins , Genotype , Methicillin-Resistant Staphylococcus aureus , Microbial Sensitivity Tests , Oxacillin , Penicillin-Binding Proteins , Staphylococcal Infections , Tertiary Care Centers , Humans , Oxacillin/pharmacology , Brazil , Anti-Bacterial Agents/pharmacology , Staphylococcal Infections/microbiology , Tertiary Care Centers/statistics & numerical data , Bacteremia/microbiology , Bacterial Proteins/genetics , Penicillin-Binding Proteins/genetics , Methicillin-Resistant Staphylococcus aureus/genetics , Methicillin-Resistant Staphylococcus aureus/drug effects , Methicillin-Resistant Staphylococcus aureus/isolation & purification , Methicillin-Resistant Staphylococcus aureus/classification , Phenotype
17.
Jpn J Infect Dis ; 77(5): 260-268, 2024 Sep 19.
Article in English | MEDLINE | ID: mdl-38825455

ABSTRACT

Biofilm-producing methicillin-resistant Staphylococcus aureus (MRSA) and coagulase-negative staphylococci (MR-CoNS) pose clinical challenges in treating healthcare-associated infections. As alternative antimicrobial options are needed, in this study, we aimed to determine the effect of curcumin-chitosan magnetic nanoparticles (Cur-Chi-MNP) on the biofilms of staphylococcal clinical isolates. MRSA and CoNS clinical isolates were identified using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. Antimicrobial susceptibility testing was performed using the broth microdilutions. Nanoparticles were synthesized by the co-precipitation of magnetic nanoparticles (MNP) and encapsulated by the ionotropic gelation of curcumin (Cur) and chitosan (Chi). Biofilm inhibition and eradication by nanoparticles, with and without the addition of oxacillin (OXA), were assessed in Staphylococcus strains. Cur-Chi-MNP showed antimicrobial activity against planktonic cells of MRSA and MR-CoNS strains and inhibited MRSA biofilm. The addition of OXA to Cur-Chi-MNP increased the biofilm inhibition and eradication activity against all staphylococcal strains (P = 0.0007), and higher biofilm activity was observed in the early biofilm stages. Cur-Chi-MNP showed antimicrobial and biofilm inhibitory activities against S. aureus. Addition of OXA increased biofilm inhibition and eradication activity against all staphylococcal strains. A combination treatment of Cur-Chi-MNP and OXA could potentially be used to treat staphylococcal biofilm-associated infections in the early stages before the establishment of biofilm bacterial cells.


Subject(s)
Anti-Bacterial Agents , Biofilms , Chitosan , Curcumin , Methicillin-Resistant Staphylococcus aureus , Microbial Sensitivity Tests , Staphylococcal Infections , Biofilms/drug effects , Chitosan/pharmacology , Chitosan/chemistry , Curcumin/pharmacology , Anti-Bacterial Agents/pharmacology , Humans , Methicillin-Resistant Staphylococcus aureus/drug effects , Staphylococcal Infections/microbiology , Staphylococcal Infections/drug therapy , Magnetite Nanoparticles/chemistry , Oxacillin/pharmacology , Staphylococcus/drug effects , Staphylococcus/physiology
18.
BMC Infect Dis ; 24(1): 645, 2024 Jun 27.
Article in English | MEDLINE | ID: mdl-38937714

ABSTRACT

BACKGROUND: Tuberculosis (TB), one of the leading causes of death worldwide, has a higher incidence among indigenous people. Albeit uncommon, autoimmune hemolytic anemia (AIHA) has been deemed a risk condition to develop mycobacterial infection, as a result of the immunosuppressive treatments. TB, in turn, can be a predisposing factor for secondary infections. CASE PRESENTATION: Here we present a case of a 28-year-old indigenous woman from Colombia, previously diagnosed with AIHA and pulmonary TB. Despite various treatments, therapies and medical interventions, the patient died after severe medullary aplasia of multiple causes, including secondary myelotoxicity by immunosuppressive therapy and secondary disseminated infections, underlining infection by Staphylococcus aureus, Klebsiella pneumoniae and Candida glabrata, which were identified as drug-resistant microorganisms. Together, this led to significant clinical complications. Invasive aspergillosis was diagnosed at autopsy. CONCLUSIONS: This report presents a rarely finding of AIHA followed by TB, and highlights the great challenges of dealing with co-infections, particularly by drug resistant pathogens. It also aims to spur governments and public health authorities to focus attention in the prevention, screening and management of TB, especially among vulnerable communities, such as indigenous people.


Subject(s)
Anemia, Hemolytic, Autoimmune , Coinfection , Humans , Female , Adult , Coinfection/microbiology , Fatal Outcome , Anemia, Hemolytic, Autoimmune/complications , Colombia , Klebsiella pneumoniae/isolation & purification , Staphylococcus aureus/isolation & purification , Candida glabrata/isolation & purification , Tuberculosis, Pulmonary/drug therapy , Tuberculosis, Pulmonary/complications , Tuberculosis, Pulmonary/microbiology , Staphylococcal Infections/microbiology , Indigenous Peoples , Candidiasis/drug therapy , Candidiasis/microbiology
19.
P R Health Sci J ; 43(2): 73-78, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38860960

ABSTRACT

OBJECTIVE: Increased mupirocin use leads to mupirocin resistance and is associated with persistence of methicillin-resistant Staphylococcus aureus (MRSA) carriers, prolonged hospitalization, and significant economic burdens for health systems. The study aimed to investigate the antimicrobial activity of compounds of Salvia rosmarinus L. ("rosemary", formerly Rosmarinus officinalis), alone or in combination with mupirocin, against multidrug resistant MRSA using isolates obtained from pediatric patients. METHODS: The in vitro antibacterial activity of the monoterpene α-pinene (α-Pi), a rosemary essential oil constituent, alone and in combination with mupirocin, was evaluated by determining the minimum inhibitory concentrations and minimum bactericidal concentrations (MBCs) and the fractional inhibitory concentration indices (FICIs) and fractional bactericidal concentration indices against multidrug-resistant clinical MRSA strains. The in vivo efficacy of α-Pi, alone and in combination with mupirocin, to eradicate MRSA infection was determined using an optimized mouse model of MRSA-infected wounds. Mouse skin samples (obtained via biopsy) were assessed for toxicity, and rabbit skin samples for irritation. RESULTS: Both in vitro and in vivo, α-Pi was active against MRSA strains and acted synergistically with mupirocin against MRSA strains. Mupirocin-monoterpene combinations exhibited FICI values of 0.2 to 0.4, reducing the MBC of topical mupirocin 33-fold. A topical formulation containing α-Pi and mupirocin enhanced the efficacy of mupirocin in an in vivo MRSA-infected mouse skin model without significantly harming the skin of mice and rabbits. CONCLUSIONS: A topical formulation combining mupirocin and α-Pi may aid in the development of innovative agents for treating MRSA infections.


Subject(s)
Anti-Bacterial Agents , Bicyclic Monoterpenes , Drug Resistance, Multiple, Bacterial , Drug Synergism , Drug Therapy, Combination , Methicillin-Resistant Staphylococcus aureus , Microbial Sensitivity Tests , Mupirocin , Mupirocin/administration & dosage , Mupirocin/pharmacology , Methicillin-Resistant Staphylococcus aureus/drug effects , Animals , Mice , Anti-Bacterial Agents/administration & dosage , Anti-Bacterial Agents/pharmacology , Bicyclic Monoterpenes/administration & dosage , Bicyclic Monoterpenes/pharmacology , Humans , Monoterpenes/pharmacology , Monoterpenes/administration & dosage , Staphylococcal Infections/drug therapy , Staphylococcal Infections/microbiology , Disease Models, Animal , Female
20.
Acta Ortop Mex ; 38(3): 172-178, 2024.
Article in Spanish | MEDLINE | ID: mdl-38862147

ABSTRACT

INTRODUCTION: intravenous antibiotic prophylaxis has significantly reduced the incidence of periprosthetic joint infection (PJI) in knee surgeries. However, for patients colonized with methicillin-resistant Staphylococcus aureus (MRSA) or those at risk of colonization, prophylaxis should include vancomycin. Intraosseous (IO) administration of vancomycin could enhance its effectiveness in total knee arthroplasty (TKA). MATERIAL AND METHODS: a retrospective review was conducted, including 143 patients at risk of PJI scheduled for TKA who received IO vancomycin along with intravenous (IV) cefazolin, referred to as group I (GI), between May 2021 and December 2022. The occurrence of complications in the first three postoperative months was evaluated. Results were compared with 140 patients without risk factors who received standard IV prophylaxis, designated as group II (GII). RESULTS: in GI, 500 mg of IO vancomycin was administered, injected into the proximal tibia, in addition to standard IV prophylaxis. In GII, patients received only IV cefazolin. The incidence of complications was 1.64% in GI and 1.4% in GII. The PJI rate at 90 postoperative days was 0.69% in GI and 0.71% in GII. CONCLUSIONS: IO vancomycin administration, along with standard IV prophylaxis, provides a safe and effective alternative for patients at risk of MRSA colonization. This approach minimizes complications associated with IV vancomycin use and addresses logistical challenges of timely administration.


INTRODUCCIÓN: la profilaxis antibiótica intravenosa ha reducido significativamente la incidencia de infección articular periprotésica (IAP) en cirugías de rodilla. No obstante, para pacientes colonizados con Staphylococcus aureus resistente a meticilina (SARM) o aquellos con riesgo de colonización, la profilaxis debe incluir vancomicina. La administración intraósea de vancomicina podría potenciar su efectividad en la artroplastía total de rodilla. MATERIAL Y MÉTODOS: se realizó una revisión retrospectiva que incluyó a 143 pacientes en riesgo de IAP programados para artroplastía total de rodilla que recibieron vancomicina intraósea junto a cefazolina intravenosa (IV), a quienes denominamos grupo I (GI), entre mayo de 2021 y diciembre de 2022. Se evaluó la aparición de complicaciones en los primeros tres meses postoperatorios. Los resultados se compararon con 140 pacientes sin factores de riesgo que recibieron profilaxis intravenosa estándar, denominados grupo II (GII). RESULTADOS: en el GI, se administraron 500 mg de vancomicina intraósea, inyectados en la tibia proximal, además de la profilaxis intravenosa estándar. En el GII, los pacientes recibieron sólo cefazolina intravenosa. La incidencia de complicaciones fue de 1.64% en el GI y de 1.4% en el GII. La tasa de IAP a los 90 días postoperatorios fue de 0.69% en el GI y de 0.71% en el GII. CONCLUSIONES: la administración de vancomicina intraósea, junto con la profilaxis intravenosa estándar, ofrece una alternativa segura y eficaz para pacientes con riesgo de colonización por SARM. Este enfoque minimiza las complicaciones asociadas con el uso intravenoso de vancomicina y soluciona los desafíos logísticos de la administración oportuna.


Subject(s)
Anti-Bacterial Agents , Antibiotic Prophylaxis , Arthroplasty, Replacement, Knee , Cefazolin , Prosthesis-Related Infections , Vancomycin , Humans , Vancomycin/administration & dosage , Vancomycin/therapeutic use , Retrospective Studies , Arthroplasty, Replacement, Knee/adverse effects , Male , Female , Aged , Anti-Bacterial Agents/administration & dosage , Anti-Bacterial Agents/therapeutic use , Antibiotic Prophylaxis/methods , Middle Aged , Prosthesis-Related Infections/prevention & control , Prosthesis-Related Infections/etiology , Cefazolin/administration & dosage , Cefazolin/therapeutic use , Methicillin-Resistant Staphylococcus aureus/drug effects , Infusions, Intraosseous , Aged, 80 and over , Staphylococcal Infections/prevention & control
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