May Staphylococcus lugdunensis Be an Etiological Factor of Chronic Maxillary Sinuses Infection?

Staphylococcus lugdunensis is an opportunistic pathogen found in the healthy human skin microbiome bacterial community that is able to cause infections of diverse localization, manifestation, and course, including laryngological infections, such as necrotizing sinusitis. Chronic maxillary sinusitis is a disease present in up to one third of European and American populations, and its etiology is not fully described. Within this study, we aimed to characterize 18 S. lugdunensis strains recovered from maxillary sinuses and evaluate them as etiological agents of chronic disease. We performed MLST analysis, the complex analysis of both phenotypic and genetic virulence factors, antibiotic susceptibility profiles, and biofilm formation assay for the detection of biofilm-associated genes. Altogether, S. lugdunensis strains were clustered into eight different STs, and we demonstrated several virulence factors associated with the chronic disease. All tested strains were able to produce biofilm in vitro with numerous strains with a very strong ability, and overall, they were mostly susceptible to antibiotics, although we found resistance to fosfomycin, erythromycin, and clindamycin in several strains. We believe that further in-depth analysis of S. lugdunensis strains from different niches, including the nasal one, should be performed in the future in order to reduce infection rate and broaden the knowledge about this opportunistic pathogen that is gaining attention.

Coagulase-negative staphylococci (CoNS) as a significant etiological factor of laryngological infections: a review.

This review article shows that coagulase-negative staphylococci (CoNS) are widely responsible for laryngological diseases. General characteristics of CoNS infections are shown in the introduction, and the pathogenicity in terms of virulence determinants, biofilm formation and genetic regulation mechanisms of these bacteria is presented in the first part of the paper to better display the virulence potential of staphylococci. The PubMed search keywords were as follows: CoNS and: nares infections, nasal polyps, rhinosinusitis, necrosing sinusitis, periprosthetic joint infection, pharyngitis, osteomyelitis of skull and neck bones, tonsillitis and recurrent tonsillitis. A list of laryngological infections and those related to skull and neck bones was presented with descriptions of the following diseases: rhinosinusitis, necrotizing sinusitis, nasal polyps, nares and nasal skin infections, periprosthetic joint infections, osteomyelitis, pharyngitis, and tonsillitis. Species identification and diagnostic problems challenging for diagnosticians are presented. Concluding remarks regarding the presence of CoNS in humans and their distribution, particularly under the effect of facilitating factors, are mentioned.

Effects of macroporous monofilament mesh on infection in a contaminated field.

BACKGROUND: The aim of this study was to evaluate whether the type of the mesh and proper surgical technique can influence the outcome of a tension-free hernia repair in a contaminated filed. MATERIALS AND METHODS: This study was based on the model of bacterial peritonitis in rats induced with a mixture composed of Escherichia coli and Bacteroides fragilis. Two animals were used as a control group without induced peritonitis and 10 animals with mesh implanted inside of the peritoneal cavity. For the 20 animals in the studied group, bacterial fluid was applied into the abdominal cavity together with the mesh implantation. In 10 cases, the mesh was fixed flatly upon the surface of the peritoneum; in the other 10, the mesh was rolled and then fixed within the peritoneal cavity. After 5 weeks, the animals were operated on again, and the meshes, the peritoneal fluid and, if present, any granulomas were taken for bacterial cultivation. RESULTS: The results of the bacterial cultivation of the material from the control group (without mesh) and from the rats with flatly fixed mesh were almost completely negative (0/10 and 1/10, respectively). In 9 out of 10 rats that were exposed to the rolled mesh for 5 weeks, the colonisation of meshes with both B. fragilis and E. coli was found (p < 0.0198). CONCLUSIONS: When properly fixed, flat mesh, even in a contaminated field, may allow for a proper mesh healing and does not influence the ability to cure bacterial peritonitis in an animal model. A bad surgical technique, such as inadequately positioned or rolled mesh, may cause persistent peritoneal bacteraemia.

Candidaemia in polish hospitals - a multicentre survey.

Significant changes in the frequency of candidaemia and the distribution of causative species have been noted worldwide in the last two decades. In this study, we present the results of the first multicentre survey of fungaemia in Polish hospitals. A total of 302 candidaemia episodes in 294 patients were identified in 20 hospitals during a 2-year period. The highest number of infections was found in intensive care (30.8%) and surgical (29.5%) units, followed by haematological (15.9%), 'others' (19.2%) and neonatological (4.6%) units. Candida albicans was isolated from 50.96% of episodes; its prevalence was higher in intensive care unit and neonatology (61.22% and 73.33%, respectively), and significantly lower in haematology (22%; P < 0.001). The frequency of C. krusei and C. tropicalis was significantly higher (24% and 18%) in haematology (P < 0.02); whereas, the distribution of C. glabrata (14.1%) and C. parapsilosis (13.1%) did not possess statistically significant differences between compared departments. Obtained data indicates that species distribution of Candida blood isolates in Polish hospitals reflects worldwide trends, particularly a decrease in the prevalence of infections due to C. albicans.

[Sensitivity for antibiotics among the E. coli strains isolated from patients with different clinical stage of infection]. / Antybiotykowrazliwosc szczepów E. coli wyizolowanych z lozyska krwionosnego pacjentów w róznym stopniu zaawansowania klinicznego zakazenia krwi.

Enteric rods are the microorganisms most commonly isolated from blood of hospitalized patients. Bloodstream infections caused by them are associated with significant patient mortality. The aim of the study was analysis of clinical course and evaluation of clinical response on bloodstream infection caused by Escherichia coli. Microorganisms were evaluated for sensibility for antibacterial drugs. For that reason MIC (Minimal Inhibitory Concentration) of antibiotics from different groups was determined for E. coli strains isolated from patients with different clinical stage of infection. No significant differences were shown in sensitivity for antibiotics and MIC among the E. coli strains in correlation with clinical condition of studied patients.

First Case of Staphylococci Carrying Linezolid Resistance Genes from Laryngological Infections in Poland.

Linezolid is currently used to treat infections caused by multidrug-resistant Gram-positive cocci. Both linezolid-resistant S. aureus (LRSA) and coagulase-negative staphylococci (CoNS) strains have been collected worldwide. Two isolates carrying linezolid resistance genes were recovered from laryngological patients and characterized by determining their antimicrobial resistance patterns and using molecular methods such as spa typing, MLST, SCCmec typing, detection of virulence genes and ica operon expression, and analysis of antimicrobial resistance determinants. Both isolates were multidrug resistant, including resistance to methicillin. The S. aureus strain was identified as ST-398/t4474/SCCmec IVe, harboring adhesin, hemolysin genes, and the ica operon. The S. haemolyticus strain was identified as ST-42/mecA-positive and harbored hemolysin genes. Linezolid resistance in S. aureus strain was associated with the mutations in the ribosomal proteins L3 and L4, and in S. haemolyticus, resistance was associated with the presence of cfr gene. Moreover, S. aureus strain harbored optrA and poxtA genes. We identified the first case of staphylococci carrying linezolid resistance genes from patients with chronic sinusitis in Poland. Since both S. aureus and CoNS are the most common etiological factors in laryngological infections, monitoring of such infections combined with surveillance and infection prevention programs is important to decrease the number of linezolid-resistant staphylococcal strains.

Escherichia coli Strains with Virulent Factors Typical for Uropathogens were Isolated from Sinuses from Patients with Chronic Rhinosinusitis-Case Report.

Escherichia coli were isolated from three patients with chronic rhinosinusitis (CRS) by intraoperative sinus tissue biopsy. Taking into account the unusual replicative niche and previous treatment failures, it was decided to focus on the virulence and drug resistance of these bacteria. The strains turned out to be multi-sensitive, but the rich virulence factors profile of bacteria typical for phylogenetic group B2 deserved attention. Tests were carried out for the presence of 32 genes using the PCR method. Particularly noteworthy are the toxins Cnf-1, HlyA, Usp-an extensive iron uptake system (enterobactin, salmochelin, yersiniabactin and outer membrane hemin receptor ChuA)-SPATE autotransporters such as vat and pic, Ag43 autoaggregative protein-important for biofilm formation-and TosA/B which enhance the fitness of E.coli. All these virulence factors are identified predominantly in UPEC strains and provide a fitness advantage during colonization of the sinuses. Patients with CRS should be asked for past or present UTI. The specific virulence factors of E. coli that facilitate the colonization of the GI tract and urinary tract may also favor the colonization of a new ecological niche (sinuses) as a result of microbial imbalance or dysbiosis.

Linezolid-resistant Enterococcus faecium strains isolated from one hospital in Poland -commensals or hospital-adapted pathogens?

One of the most pressing problems of enterococci infections is occurring resistance to linezolid, which is an antibiotic used in the treatment of infections caused by vancomycin-resistant strains (VRE). The main objective of our research was to investigate the relationship of 19 linezolid-resistant E. faecium isolates from 18 patients hospitalized at Clinical Hospital in Gdansk (Poland). One of the LZDREF was isolated in 2003 (K2003), and another 18 were collected from 2013 to 2017. Genotyping with PCR MP method indicated 14 main unrelated genetic profiles and no association with K2003 strain. Two isolates with the same genotype and genetically closely related two sub-types (2 isolates for each sub-type) were hospital-derived colonizations of patients. The other unrelated genotypes were discussed in the context of colonization, nosocomial infections, and commensal origin, taking into account prior exposure to linezolid. We determined the presence of a point mutation G2576T in six loci of 23S rDNA. There was also a significant correlation (p<0.0015) between the presence of MIC>32 value and the presence of G2576T point mutation on the sixth rrn. We also detected 5 virulence genes for all isolates: gelE, cylA, asa1, hyl, esp. Correlation (p≤0.0001) was observed between the presence of gelE gene encoding gelatinase and two other genes: cylA and asa1 encoding cytolysin and collagen binding protein responsible for aggregation of bacterial cells, respectively. Significant correlation was also observed between asa1 and cfr genes encoding 23S rRNA rybonuclease responsible for resistance to PhLOPSA antibiotics (p = 0.0004). The multidimensional analysis has also shown the correlation between cfr gene and GI-tract (p = 0, 0491), which suggests horizontal gene transfer inside the gut microbiota and the risk of colonization with linezolid-resistant strains without previously being treated with the antibiotic. The patient could have been colonized with LZDRVREF strains which in the absence of competitive microbiota quickly settle in ecological niches favourable for them and pose a risk for the patient.

An Overview of the Application of Systems Biology in an Understanding of Chronic Rhinosinusitis (CRS) Development.

Chronic rhinosinusitis (CRS) is an inflammatory disease of the paranasal sinuses. It is defined as the presence of a minimum of two out of four main symptoms such as hyposmia, facial pain, nasal blockage, and discharge, which last for 8-12 weeks. CRS significantly impairs a patient's quality of life. It needs special treatment mainly focusing on preventing local infection/inflammation with corticosteroid sprays or improving sinus drainage using nasal saline irrigation. When other treatments fail, endoscopic sinus surgery is considered an effective option. According to the state-of-the-art knowledge of CRS, there is more evidence suggesting that it is more of an inflammatory disease than an infectious one. This condition is also treated as a multifactorial inflammatory disorder as it may be triggered by various factors, such as bacterial or fungal infections, airborne irritants, defects in innate immunity, or the presence of concomitant diseases. Due to the incomplete understanding of the pathological processes of CRS, there is a continuous search for new indicators that are directly related to the pathogenesis of this disease-e.g., in the field of systems biology. The studies adopting systems biology search for possible factors responsible for the disease at genetic, transcriptomic, proteomic, and metabolomic levels. The analyses of the changes in the genome, transcriptome, proteome, and metabolome may reveal the dysfunctional pathways of inflammatory regulation and provide a clear insight into the pathogenesis of this disease. Therefore, in the present paper, we have summarized the state-of-the-art knowledge of the application of systems biology in the pathology and development of CRS.

Multidrug-resistant strains of coagulase-negative staphylococci isolated from patients with chronic sinusitis - MDR, XDR, PDR strains.

INTRODUCTION: The development of resistance to multiple antimicrobial agents in pathogenic bacteria has become a threat to public health. Multidrug-resistant strains that are particularly dangerous include MDR, XDR and PDR strains. MATERIAL AND METHODS: Aspirate material from paranasal sinuses, obtained from patients with chronic sinusitis undergoing functional endoscopic sinus surgery (FESS) in Medical Center MML in Warsaw, was subjected to bacteriologic analysis. The isolated strains were identified to the species level and tested for antibiotic resistance. Then, minimal inhibitory concentration (MIC) was determined. R esults: The isolated strains of coagulase-negative staphylococci were resistant mainly to macrolides, aminoglycosides and tetracycline. Nine of the isolated strains exhibited multidrug-resistance. DISCUSSION: Bacteria causing chronic sinusitis are becoming increasingly resistant to antimicrobial agents. The diagnostic process for coagulase-negative staphylococci (CNS) is often limited to the identification of species, or even genus of the bacteria. The CNS strains are considered to be non-pathogenic and they are not subject to eradication. This may lead to erroneous therapeutic decisions and, consequently, to the development of antibiotic resistance. CNS infections are classified as nosocomial and therefore, appropriate epidemiological procedures have to be followed. The authors highlight the necessity to determine MIC values for antibiotics and to introduce personalized treatment.

Intra-operative biopsy in chronic sinusitis detects pathogenic Escherichia coli that carry fimG/H, fyuA and agn43 genes coding biofilm formation.

The aim of this study was to investigate whether or not surgical biopsy of sinus tissue in chronic sinusitis, not responsive to treatment, would detect E. coli. We intended to evaluate E. coli virulence genes, therefore dispute the causal role of such an unusual microorganism in chronic sinusitis, as well as consider effective pathogen-targeted therapy. Patients with E. coli isolated by intra-operative puncture biopsy were included in the study. Genetic analysis of E. coli isolates, including phylogenetic grouping and virulence factor characteristics, were done by multiplex PCR. We identified 26 patients with chronic sinusitis, in which 26 E. coli isolates were cultured. The E. coli isolates belonged mainly to pathogenic phylogenetic group B2, and carried multiple virulence genes. Three genes in particular were present in all (100%) of examined isolates, they were (1) marker agn43 gene for forming biofilm, (2) type 1 fimbriae (fimG/H gene) and (3) yersiniabactin receptor (fyuA). Furthermore, a pseudo-phylogenetic tree of virulence genes distribution revealed possible cooperation between agn43, fimG/H, and fyuA in the coding of biofilm formation. Intra-operative-biopsy and culture-based therapy, targeting the isolated E. coli, coincided with long-term resolution of symptoms. This is the first report demonstrating an association between a highly pathogenic E. coli, chronic sinus infection, and resolution of symptoms upon E. coli targeted therapy, a significant finding due to the fact that E. coli has not been considered to be a commensal organism of the oropharynx or sinuses. We postulate that the simultaneous presence of three genes, each coding biofilm formation, may in part account for the chronicity of E. coli sinusitis.

ADSRRS-fingerprinting and PCR MP techniques for studies of intraspecies genetic relatedness in Staphylococcus aureus.

The present study was designed to evaluate the usefulness of two novel molecular typing methods, amplification of DNA fragments surrounding rare restriction sites (ADSRRS-fingerprinting) and the PCR melting profile (PCR MP), for Staphylococcus aureus strain differentiation. Thirty-seven S. aureus strains isolated from patients with a history of furunculosis were studied. The strains were identified by determining several phenotypic properties and were genotyped using three differentiation methods: macrorestriction analysis of the chromosomal DNA by pulsed-field gel electrophoresis (REA-PFGE), ADSRRS-fingerprinting, and PCR MP technique. In some cases the results obtained showed that the S. aureus isolated from the nose was identical to the one from the furuncle of the same patient. The same genotype was also identified for S. aureus strains isolated from two different members of a family with a history of recurrent furunculosis, although the active lesions were present in only one of them when the investigation was done. Results from strain genotyping illustrated that the recently developed ADSRRS-fingerprinting and PCR MP techniques are useful for studies of intraspecies genetic relatedness of S. aureus strains. They are as effective in discriminating closely related strains as the PFGE method, which is currently considered to be "the gold standard" for epidemiological studies.

PCR melting profile method for genotyping analysis of vancomycin-resistant Enterococcus faecium isolates from Hematological Unit patients.

A number of Enterococcus strains with high-level inducible resistance to vancomycin have been identified, and the relative incidence of these strains has increased significantly in the last years. The first outbreak caused by vancomycin-resistant enterococci in Poland was reported in 1999. Vancomycin-resistant Enterococcus faecium is known for its propensity to cause infections which are difficult to eradicate. In this study, we determined the genetic similarities between vancomycin-resistant E. faecium isolates consecutively recovered from single patients to assess the duration of infection or colonization. The isolates taken in the study were identified by the conventional methods as E. faecium. PCR melting profile (PCR-MP) and pulsed-field gel electrophoresis (PFGE) typing revealed that the isolates belonged to six distinct genotypes and that two of them were predominant. Consecutive E. faecium isolates with identical genotypes were found in 7 of 12 (58.0%) patients. The delay between the times of recovery of the first and last isolates of identical genotypes from each patient was from 9 days to about 1 year. In six patients, paired blood and non-blood isolates showed identical genotypes. Data presented here demonstrate the complexity of the epidemiological situation concerning vancomycin-resistant enterococci that may occur in a single medical ward. We also show for the first time the evaluation of PCR-MP technique in enterococci strains differentiation and we revealed that there is at least a similar power of discrimination between the present gold-standard REA-PFGE and a PCR-MP method.

[PCR MP (PCR melting profile) technique--possibilities of application in epidemiological studies]. / Technika PCR MP (PCR melting profile)--mozliwosci zastosowania w badaniach epidemiologicznych.

The performance and convenience of a PCR melting profile (PCR MP) technique based on using low denaturation temperatures during ligation mediated PCR (LM PCR) of bacterial DNA is shown. We found that PCR MP technique is a rapid method that offers good discriminatory power, excellent reproducibility and may be applied for epidemiological studies. Results from strain genotyping illustrate that PCR MP is useful for the study of intraspecific genetic relatedness of strains and is as effective in discriminating closely related strains as the PFGE method, which is currently considered to be the gold standard for epidemiological studies. The usefulness of the PCR MP for molecular typing was shown for clinical strains of Escherichia coli, Enterococcus faecium VRE and Stapylococcus aureus.

[Study of genetic diversity of nontypeable Haemophilus influenzae strains isolated from healthy children and patients with infection symptoms]. / Genetyczna zmiennosc bezotoczkowych szczepów Haemophilus influenzae izolowanych od nosicieli i chorych dzieci z objawami zakazen.

In the study the usefulness of genotyping methods for genetic variability examinations of non-typeable H. influenzae strains circulating in population as well as level the variability of NTHi strains isolated from healthy children and from symptomatic infection cases have been evaluated. Among genotyping methods evaluated, AFLP method of the MfeI/BglII set has been found most useful to study level of genetic variability of NTHi strains population. It has been shown that NTHi strains colonizing nasopharyngeal of healthy children present higher polymorphism level than strains isolated from patient with clinical symptoms of NTHi infection.

[Estimation of the frequency of occurrence of microorganisms isolated from blood cultures of hospitalized patients in the Hospital of Medical University in Gdansk in 2000-2002]. / Ocena czestosci wystepowania drobnoustrojów izolowanych z krwi pacjentów hospitalizowanych w Szpitalu Klinicznym Akademii Medycznej w Gdansku w latach 2000-2002.

The aim of present study was retrospective analysis of the frequencies of occurrence of the most common microorganisms isolated from blood cultures in the Medical University in Gdansk from 2000 to 2002. The blood patterns were taken from adult patients with symptoms suggesting bacteriemia. During the 3 year study period 31788 blood samples were obtained, of which 5520 (17.37%) were positive. The number of Gram-positive bacteria isolated from blood increased and the rate of Gram-negative bacteria decreased over the study period. In addition the increase of frequency of Candida, VRE and Escherichia coli was noted. The number of infections caused by MRSA and Gram-negative ESbetaL+ diminished during time of observation. Acquaintance on the most frequently isolated organisms from blood patterns and they antimicrobial susceptibility should guide the choice of empiric antimicrobial regimens for patients with bacteriemia.

Evidence for tetracycline resistance determinant tet(M) allele replacement in a Streptococcus pneumoniae population of limited geographical origin.

A collection of 185 Streptococcus pneumoniae isolates was tested for their susceptibility to antipneumococcal drugs, with a focus on the distribution of tetracycline resistance determinants tet(M) and tet(O). Resistance patterns were compared with established correlates of multidrug resistance, and tetracycline-resistant isolates were tested for clonality and allelic variation within tet(M). Resistance to tetracyclines, penicillins and macrolides were all strongly related to multidrug resistance. Over one-quarter of the strains were tetracycline resistant, all via the tet(M)-mediated mechanism. Restriction fragment length polymorphism analysis revealed a high degree of allelic variation within tet(M) and gave evidence of a clonal and horizontal spread of selected alleles. A tet(M) variant that emerged with the onset of epidemic multidrug-resistant strains was replacing old alleles in the population.

[Study on genetic diversity of genes encoding main adhesins among nontypeable Haemophilus influenzae strains isolated from children in Poland]. / Badania profilu determinant genetycznych kodujacych glówne adhezyny bezotoczkowych szczepów Haemophilus influenzae izolowanych od dzieci w Polsce.

The study was based on hypothesis that in the nontypeable population of H. influenzae strains isolated from children there are some genetically predisposed to induce symptomatic infection in children and that they might be divided into different groups depending on profiles of genes encoding main adhesins synthesis. The work aimed at analysis of distribution of genes encoding adhesins and evaluation of domination possibility of some strains representing particular adhesins genes profiles among NTHi population. Results of the study revealed that among population of NTHi strains, distribution of genes encoding main adhesins are differing. Among children, NTHi strains harbouring genes encoding HA and HMW1/HMW2 adhesins were more prevalent in healthy children and in children with symptomatic infections, respectively. Analysis of strains harbouring main adhesins profiles might be a useful screening method in monitoring strains circulating among children, in order to determine the most invasive NTHi strains.

[Procalcitonin as a diagnostic marker in systemic inflammatory response syndrome (SIRS) and sepsis]. / Prokalcytonina jako marker diagnostyczny Zespolu Uogólnionej Reakcji Zapalnej (SIRS) i posocznicy.

OBJECTIVE: Evaluation the value of procalcitonin as a diagnostic and prognostic marker in septic patients and patients with systemic inflammatory response syndrome (SIRS). MATERIAL AND METHODS: 126 patients were included into the study. The patients were divided into four groups: 1--septic patients with positive blood cultures, 2--septic patients with negative blood cultures, 3--patients with SIRS, 4--patients without sepsis and SIRS. PCT level was measured by imunoluminometric assay (LUMItest) and immunochromatographic assay (PCT-Q). RESULTS: PCT level is higher in patients with sepsis than in patients with SIRS. PCT level is only slightly elevated in patients without sepsis and SIRS. The highest PCT level is found in patients with septic shock. In patients with the clinical improvement the frequency of PCT level increase is approximately twice lower than in patients who died. CONCLUSIONS: Measurement of PCT level on the first, second and third day of hospitalization has no prognostic value. There is no significant difference in PCT level in sepsis caused by Gram positive and Gram negative bacteria. PCT is a useful marker in diagnosis of sepsis but its role in monitoring the severity of sepsis requires more clinical studies.

[Nosocomial bacteremia]. / Bakteriemie szpitalne.

Nosocomial bacteremia according to different authors can be divided in to bacteremia persistent, polymicrobial bacteremia, alternate bacteremia, breakthrough bacteremia, different bacteremia. Developing techniques of microbiological and molecular diagnostics induce us to verify the definition and partition of term "bacteremia".