Exposing Salmonella Senftenberg and Escherichia coli Strains Isolated from Poultry Farms to Formaldehyde and Lingonberry Extract at Low Concentrations.

European Union (EU) countries strive to improve the quality and safety of food of animal origin. Food production depends on a good microbiological quality of fodder. However, feed can be a reservoir or vector of pathogenic microorganisms, including Salmonella or Escherichia coli bacteria. Salmonella spp. and E. coli are the two most important food-borne pathogens of public health concern. Contamination with these pathogens, mainly in the poultry sector, can lead to serious food-borne diseases. Both microorganisms can form biofilms on abiotic and biotic surfaces. The cells that form biofilms are less sensitive to disinfectants, which in turn makes it difficult to eliminate them from various surfaces. Because the usage of formaldehyde in animal feed is prohibited in European countries, the replacement of this antibacterial with natural plant products seems very promising. This study aimed to assess the inhibitory effectiveness of Vaccinium vitis-idaea extract against biofilm produced by model Salmonella enterica and E. coli strains. We found that formaldehyde could effectively kill both species of bacterial cells in biofilm, while the lingonberry extract showed some antibiofilm effect on S. enterica serovar Senftenberg. In conclusion, finding natural plant products that are effective against biofilms formed by Gram-negative bacteria is still challenging.

Antiviral Potential of Plants against Noroviruses.

Human noroviruses, which belong to the enterovirus family, are one of the most common etiological agents of food-borne diseases. In recent years, intensive research has been carried out regarding the antiviral activity of plant metabolites that could be used for the preservation of fresh food, because they are safer for consumption when compared to synthetic chemicals. Plant preparations with proven antimicrobial activity differ in their chemical compositions, which significantly affects their biological activity. Our review aimed to present the results of research related to the characteristics, applicability, and mechanisms of the action of various plant-based preparations and metabolites against norovirus. New strategies to combat intestinal viruses are necessary, not only to ensure food safety and reduce infections in humans but also to lower the direct health costs associated with them.

The influence of diet on gastrointestinal Candida spp. colonization and the susceptibility of Candida spp. to antifungal drugs

Background: Candida spp. has been identified as the most common member of human gut microbiota. This yeast-like fungus is recognized as an opportunistic organism due to its potential to cause diseases in all parts of the gastrointestinal tract. Objective: The aim of the study was to investigate the relationship between diet and health of the study participants and the presence of gastrointestinal Candida spp. Susceptibility of Candida to antifungal drugs was determined. Material and methods: Material comprised of oral swabs and fecal samples self-collected by the study participants. The participants filled in a nutritional questionnaire. A total of 30 people took part in the study, including 28 women and 2 men. The study was conducted in Wroclaw, Poland. Susceptibility of Candida to antifungal drugs was determined using Bio-Rad's FUNGITEST™ Kit designed for the susceptibility testing of yeasts to six antifungal drugs. Results: In the group with negative Candida spp. cultures, healthier wheat flour substitutes were consumed significantly more frequently than in the group with positive Candida spp. cultures. Yellow cheeses and quark were eaten significantly more frequently in the group with negative Candida spp. cultures. No antifungal resistance was detected in the study group. Conclusions: The increased consumption of purified wheat flour products was linked to the presence of gastrointestinal Candida spp. A higher consumption of cheese was observed in the group with negative Candida spp. cultures, which may indicate the inhibitory effect of saturated fatty acids on the growth of human Candida spp. Sensitivity of C. albicans to antifungal drugs may increase effectiveness of candidiasis treatment.

PCR diagnostics of Chlamydia trachomatis in asymptomatic infection by women.

OBJECTIVES: Chlamydial infection is often asymptomatic. The lack of symptoms may result in the infection developing into a chronic. Chlamydial infections of the genitourinary system in women can lead to serious complications like PID, fallopian tubes infertility, ectopic pregnancy, and chronic pelvic pain. An infection of the genitourinary system does not cause any lasting immune resistance and does not protect against re-infection. The aim of this research was to conduct tests for Chlamydia trachomatis on healthy women without any genital system symptoms and to estimate the frequency of asymptomatic infections. MATERIAL AND METHODS: During preventive examinations a cervical smear was obtained from the patients n = 100. The aver-age age of the patients was 24.86 ± 3.15. The swabs were sampled by gynecologists. During the examinations Geneproof PathogenFree DNA isolation Kit and GeneProof Chlamydia trachomatis PCR kit which detects 16S rRNA conservative coding sequence, conservative region of cryptic plasmid DNA, including deletion mutation in cryptic plasmid (Swedish variant). RESULTS: Swabs were sampled from 100 women aged 18-32 who had no symptoms of chlamydial genitourinary system infection. Within the study group 4% of women received a positive result, i.e. 4/100. CONCLUSIONS: The study confirmed asymptotic infection in 4% of women. In own research it was not possible to confirm cor-relation between the presence of Chlamydia trachomatis and the number of partners or the number of sexual intercourses.

[Selected aspects of Chlamydophila pneumoniae infections]. / Wybrane aspekty zakazenChlamydophila pneumonia.

Chlamydophila pneumoniae was taxonomically separated from strain TWAR - an abbreviation of the strain isolated from humans TW-183 (material from the eye of a child in Taiwan in 1965) and AR-39 (material from a student's throat swab with acute changes within airways in Seattle in 1983). The basis of separation of the C. pneumoniae species was the unique structure of the elementary bodies. Infection caused by C. pneumoniae is often asymptomatic (60-80% of all infections). Symptomatic infections of the upper respiratory tract relate to pharyngitis, laryngitis, sinusitis and the lower respiratory tract: bronchitis and pneumonia. C. pneumoniae infection often transforms into a chronic, clinically oligo- or asymptomatic form. The chronic inflammatory process is associated by many authors with the pathogenesis of coronary artery disease, endocarditis, atherosclerosis, hypertension, vasculitis, multiple sclerosis, sarcoidosis, and asthma. C. pneumoniae has a specific tropism and exhibits cytotoxic activity towards the airway epithelium, in which it proliferates and destroys infected cells by lysis. Entry of these bacteria to the human body leads to activation of first non-specific and then specific resistance mechanisms and the development of a local inflammatory process. Diagnosis of C. pneumoniae should be confirmed only after the exclusion of typical micro-organisms causing respiratory infections. It is important to pay attention to the fact that the epidemiological data on the incidence of C. pneumoniae infections in different age groups of patients are variable depending on the type of diagnostic methods used in the research. Chlamydia are resistant to most antibiotics that are routinely used in respiratory tract infections. These bacteria are susceptible to antibiotics that disrupt the synthesis of DNA and proteins, such as macrolides, tetracyclines, and fluoroquinolones.

[The role of Escherichia coli strain Nissle 1917 in the gastro-intestinal diseases]. / Rola bakterii Escherichia coli szczep Nissle 1917 w chorobach przewodu pokarmowego.

In this paper a review of the researches on the role of Escherichia coli strain Nissle 1917 (EcN) in gastrointestinal diseases was presented. EcN is a non-pathogenic strain of the Enterobacteriaceae family, which has probiotic properties. In a number of studies conducted among humans and  experimental animals the application of EcN in treatment of gastrointestinal diseases was observed. Most studies about EcN has been devoted to this organism efficacy in ulcerative colitis treatment. Comparable results were obtained, by citied authors, in the treatment (sustaining remission) of EcN and mesalazine in ulcerative colitis. Moreover, this probiotic therapy, compared to placebo, contributes to obtaining a faster remission and improvement of intestinal histopathology. The use of EcN in Crohn's disease has not been the subject of as many studies as in the case of ulcerative colitis. Assessing the importance of EcN in treatment of other gastrointestinal disorders, authors of the studies observed, that in patients with irritable bowel syndrome, who receiving this probiotic there was a pain, nausea and bloating reduction. In studies conducted among children a positive impact of EcN in prevention and treatment of diarrhea was demonstrated. Similar results were obtained in studies conducted in experimental animals. Based on the presented review it can be concluded that the strain of Escherichia coli Nissle 1917 is useful in treatment of gastrointestinal diseases, especially in treatment of ulcerative colitis. This probiotic may constitute a part of treatment of irritable bowel syndrome and diarrhea. The effectiveness of this strain in treatment of Crohn's disease is not clearly established and further research are require.

Incidence of Chlamydophila pneumoniae infection in children during 2007-2010.

Chlamydophila pneumoniae is the etiological agent of pharyngitis, bronchitis, and pneumonia. The aim of the study was to evaluate the frequency of chlamydial respiratory infections in children in the Lower Silesia Region in Poland in 2007-2010. There were 2,733 throat swabs examined, obtained from hospitalized patients aged from 20 months to 18 years with various clinical symptoms such as dry cough, productive cough, and from asymptomatic ambulatory patients. An indirect immunofluorescence technique, based on monoclonal antibodies labeled with fluorescein isothiocyanate, was used for detection of Chl. pneumoniae antigen. Overall, there were 1,114, 503, 641, and 475 patients studied in the consecutive 2007, 2008, 2009, and 2010 years. There clearly were fewer patients each next year submitted for Chl. pneumoniae detection procedure, which stemmed from the declining severity of respiratory infections noted in children and thus less demanding diagnostic workup commissioned by physicians. The percentage of results positive for Chl. pneumoniae antigen amounted to 53.3, 41.6, 43.1, and 36.4 % in the consecutive years, respectively. Detection of chlamydial infections had thus a decreasing tendency in the period studied. There also were decreases in Chl. pneumoniae detection rate in cases stratified due to the presenting symptom: dry cough, productive cough, or in asymptomatic cases. A milder course of respiratory infections resulting in a decreased number of children examined for Chl. pneumoniae antigen in consecutive years, makes it difficult to draw definite conclusions on the factual incidence rate. Nevertheless, we believe we have shown, from the clinical standpoint, a dropping rate of Chl. pneumoniae detection in children with respiratory infections.

Detection of Chlamydophila pneumoniae antigens in patients with chronic cough.

The aim of this study was to analyze the rate of Chlamydophila pneumoniae infection in adults with symptoms of chronic cough. The study was conducted in 83 hospitalized patients aged 18-67 suffering of chronic cough. The control group consisted of 20 healthy age-matched subjects without any respiratory symptoms. Bacteriological tests on the presence of Chlamydophila pneumoniae antigen were performed in throat swabs by indirect immunofluorescence technique using monoclonal antibodies labeled with fluorescein isothiocyanate. The rate of Chlamydophila infected patients was examined in relation to age and gender. The Chlamydophila pneumoniae antigen was detected in 15 (18 %) out of the 83 patients; about equally in both genders. Furthermore, we found that the patients aged 28-37 constituted the age group that most frequently tested positive for Chlamydophila pneumoniae. Unraveling the presence of Chlamydia infection in chronic cough patients enables to introduce a timely implementation of effective therapy and thus can prevent distant complications.

Evolution of Antibiotic Resistance in Escherichia coli and Klebsiella pneumoniae Clinical Isolates in a Multi-Profile Hospital over 5 Years (2017-2021).

In recent years, we have witnessed a growing drug resistance among bacteria, which is associated with the use and availability of an increasing number of broad-spectrum antimicrobial agents, as well as with their irrational and excessive use. The present study aims to analyze changes in the drug resistance of Gram-negative Enterobacterales: Escherichia coli and Klebsiella pneumoniae, isolated from infections in a multi-profile hospital over five years (from 2017 to 2021). Among the practical outcomes of the evaluation of these data will be the possibility of determining changes in susceptibility to the antibiotics used in the hospital. In turn, this will help propose new therapeutic options, especially for empirical therapy that is necessary in severe infections. The analysis of the use of individual groups of antibiotics allowed for identification of the causes of the increasing resistance of Gram-negative bacilli. The highest number of infections whose etiological agent was K. pneumoniae ESBL(+) and E. coli ESBL(+) was observed in 2018. In the analyzed five-year period, the number of multi-resistant (MDR) K. pneumoniae strains increased successively, which seems to be related to the growing use, especially in the pandemic period, of broad-spectrum antibiotics, mainly penicillins with inhibitors, third-generation cephalosporins, and carbapenems.

Changes in Antibiotic Resistance of Acinetobacter baumannii and Pseudomonas aeruginosa Clinical Isolates in a Multi-Profile Hospital in Years 2017-2022 in Wroclaw, Poland.

In recent years, we have witnessed increasing drug resistance among bacteria, which is associated with the use and availability of an increasing number of broad-spectrum antimicrobials, as well as with their irrational and excessive use. The present study aims to analyze changes in the drug resistance of Gram-negative Pseudomonas aeruginosa and Acinetobacter baumannii, isolated from infections in a multi-profile hospital over a five-year period (from 2017 to 2022). Among the practical results of the evaluation of these data will be the possibility to determine changes in susceptibility to the antibiotics used in the hospital. This, in turn, will help propose new therapeutic options, especially for empirical therapy, which is essential in severe infections. Analysis of the use of different antibiotic groups has made it possible to identify the causes of increasing resistance in the analyzed Gram-negative bacilli. The highest antibiotic use was observed in the hospital between 2020 and 2022, most probably due to the COVID-19 pandemic and the higher number of patients in severe condition requiring hospitalization. Unfortunately, during the period analyzed, the number of multi-resistant strains of A. baumannii was successively increasing; this seems to be related to the increased use, especially during the pandemic period, of broad-spectrum antibiotics, mainly penicillins with inhibitors, third-generation cephalosporins and carbapenems.

Dentigenous infectious foci - a risk factor of infective endocarditis.

BACKGROUND: Dentigenous, infectious foci are frequently associated with the development of various diseases. The role of such foci in the evolution of endocarditis still remains unclear. This article presents the concluding results of an interdisciplinary study verifying the influence of dentigenous, infectious foci on the development of infective endocarditis. MATERIAL/METHODS: The study subjects were 60 adult patients with history of infective endocarditis and coexistent acquired heart disease, along with the presence at least 2 odontogenic infectious foci (ie, 2 or more teeth with gangrenous pulp and periodontitis). The group had earlier been qualified for the procedure of heart valve replacement. Swabs of removed heart valve tissue with inflammatory lesions and blood were then examined microbiologically. Swabs of root canals and their periapical areas, of periodontal pockets, and of heart valves were also collected. RESULTS: Microbial flora, cultured from intradental foci, blood and heart valves, fully corresponded in 14 patients. This was accompanied in almost all cases by more advanced periodontitis (2nd degree, Scandinavian classification), irrespective of the bacterial co-occurrence mentioned. In the remaining patients, such consistency was not found. CONCLUSIONS: Among various dentigenous, infectious foci, the intradental foci appear to constitute a risk factor for infective endocarditis.

Occurrence and Characteristics of Carbapenem-Resistant Klebsiella pneumoniae Strains Isolated from Hospitalized Patients in Poland-A Single Centre Study.

The global emergence and spread of genes responsible for the production of ESBL (extended-spectrum beta-lactamases) and carbapenemases in Klebsiella pneumoniae isolates poses a serious threat to public health. The aim of this study was to retrospectively analyze the frequency of occurrence and drug resistance of selected alarm agents isolated from patients of the specialist hospital in Wroclaw. A total of 13,528 clinical materials collected from patients of a specialist hospital in Wroclaw were analyzed in the period from 1 January 2020 to 31 December 2020. Overall, 3894 bacterial strains were isolated from clinical materials, including 416 K. pneumoniae isolates. K. pneumoniae that showed resistance to ETP (ertapenem) and/or MEM (meropenem) were tested using phenotypic tests for the detection of KPC (carbapenemase-producing Klebsiella), MBL (metallo-ß-lactamase) and OXA-48 (oxacilinase-48) carbapenemases. In the case of a positive or doubtful result of the phenotypic test, immunochromatographic tests and the CarbaNP test were performed. In total, 58 K. pneumoniae isolates resistant to 1 or more carbapenem antibiotics were isolated. Of the 58 strains, 16 (27.6%) were isolated from rectal swabs conducted on CPE (carbapenemase-producing Enterobacteriaceae) carriers. In the case of CRE (carbapenem-resistant Enterobacteriaceae) K. pneumoniae, carbapenemases were detected in 28/58 (48.3%) isolates. Notably, 23/28 K. pneumoniae isolates produced MBL/NDM (New Delhi metallo-ß-lactamase) (82.1%), 5/28 produced VIM (Verona-intergon-encoded metallo-ß-lactamase) (14.3%), and one produced MBL/NDM + OXA-48. Carbapenemases were detected in 13 of 16 (81.3%) carbapenem-resistant K. pneumoniae isolates derived from rectal swabs. The significant participation of CRE and CPE isolates in the infections proves the need to test patients admitted to hospital wards for their status as a CPE carrier in order to limit the emergence of new epidemic outbreaks.

Comparative Characteristics and Pathogenic Potential of Escherichia coli Isolates Originating from Poultry Farms, Retail Meat, and Human Urinary Tract Infection.

The pathogenicity of many bacterial strains is determined by the acquisition of virulence genes and depends on many factors. The aim of this study was to analyse the phylogenetic background, virulence patterns, and drug susceptibility of 132 E. coli isolates tested in the context of the ExPEC (Extraintestinal Pathogenic E. coli) pathotype and the correlation of these features with bacterial isolation source: food (retail meat), poultry farms (AFEC-Avian Faecal E. coli), and patients with UTI (urinary tract infection) symptoms. The drug-susceptibility results of tested E. coli isolates obtained indicate that the resistance profile-ampicillin/tetracycline/trimethoprim+sulfamethoxazole/ciprofloxacin (AMP/TE/SXT/CIP)-was most frequently observed. The multidrug resistance (MDR) phenotype was found in 31.8% of isolates from poultry farms, 36.8% of strains isolated from food, and 20% of clinical samples. The greatest similarity of virulence profiles applied to isolates derived from poultry farms and food. Most of the AFEC from poultry farms and food-derived isolates belonged to commensals from phylogroups A and B1, while among the isolates from patients with UTI symptoms, the most common was the B2 phylogroup. The collective analysis showed similarity of the three studied groups of E. coli isolates in terms of the presented patterns of antimicrobial resistance, while the virulence profiles of the isolates studied showed great diversity. The phylogroup analysis showed no similarity between the poultry/food isolates and the UTI isolates, which had significant pathogenic potential.

In Vitro Susceptibility of Multi-Drug Resistant Klebsiellapneumoniae Strains Causing Nosocomial Infections to Fosfomycin. A Comparison of Determination Methods.

INTRODUCTION: Over the past few decades, Klebsiella pneumoniae strains increased their pathogenicity and antibiotic resistance, thereby becoming a major therapeutic challenge. One of the few available therapeutic options seems to be intravenous fosfomycin. Unfortunately, the determination of sensitivity to fosfomycin performed in hospital laboratories can pose a significant problem. Therefore, the aim of the present research was to evaluate the activity of fosfomycin against clinical, multidrug-resistant Klebsiella pneumoniae strains isolated from nosocomial infections between 2011 and 2020, as well as to evaluate the methods routinely used in hospital laboratories to assess bacterial susceptibility to this antibiotic. MATERIALS AND METHODS: 43 multidrug-resistant Klebsiella strains isolates from various infections were tested. All the strains had ESBL enzymes, and 20 also showed the presence of carbapenemases. Susceptibility was determined using the diffusion method (E-test) and the automated system (Phoenix), which were compared with the reference method (agar dilution). RESULTS: For the reference method and for the E-test, the percentage of strains sensitive to fosfomycin was 65%. For the Phoenix system, the percentage of susceptible strains was slightly higher and stood at 72%. The percentage of fosfomycin-resistant strains in the Klebsiella carbapenemase-producing group was higher (45% for the reference method and E-test and 40% for the Phoenix method) than in carbapenemase-negative strains (25%, 25%, and 20%, respectively). Full (100%) susceptibility categorical agreement was achieved for the E-test and the reference method. Agreement between the automated Phoenix system and the reference method reached 86%. CONCLUSIONS: Fosfomycin appears to be the antibiotic with a potential for use in the treatment of infections with multidrug-resistant Klebsiella strains. Susceptibility to this drug is exhibited by some strains, which are resistant to colistin and carbapenems. The E-test, unlike the Phoenix method, can be an alternative to the reference method in the routine determination of fosfomycin susceptibility, as it shows agreement in terms of sensitivity categories and only slight differences in MIC values. The Phoenix system, in comparison to the reference method, shows large discrepancies in the MIC values and in the susceptibility category.

Natural Products and Their Potential Anti-HAV Activity.

The role of purified natural products in the prevention and treatment of countless diseases of bacterial, fungal, and viral origin cannot be overestimated. New antiviral drugs have been obtained from natural sources and transformed into preparations for prophylactic and therapeutic purposes. Flavonoids, polyphenols, saponins, proanthocyanins, polysaccharides, organic acids, proteins, polypeptides, and essential oils derived from plants, animals, or microorganisms can control and combat foodborne viral infections, including hepatitis A. The components of essential oils are characterized by numerous therapeutic and antioxidant properties and exhibit a broad spectrum of antimicrobial and antiviral activity. Due to these properties, they can be used to preserve meat, fruit, vegetables, and their products. Over the past two decades, much effort has been made to identify natural products, mostly of plant origin, to combat foodborne viruses. Natural plant extracts have several potential uses, not limited to increasing the safety of food products and improving their quality, but also as natural antiviral agents.

Susceptibility to Clotrimazole of Candida spp. Isolated from the Genitourinary System-A Single Center Study.

The aim of this study was to determine the susceptibility to clotrimazole of 125 isolates of Candida spp. originated from the genitourinary system of hospitalized patients as well as outpatients, tested in the mycological laboratory of Wroclaw Medical University in the years 1999-2018. The minimal inhibitory concentrations of clotrimazole and fluconazole were determined with the use of the microdilution method according to EUCAST, and the MFC was determined by subsequent subculture on Sabouraud agar. For the tested population of Candida yeasts, the MIC values of clotrimazole ranged from 0.008 to 8 mg/L, and MIC90 was 1 mg/L, whereas MIC50 was 0.008 mg/L. The minimal fungicidal concentration ranged between 1 and >8 mg/L. The great majority of the isolates (88%; 110/125) displayed MIC < 1 mg/L and were classified as WT (wild-type), whereas MIC ≥ 1 mg/L was determined for 2/61 (3.2%) isolates of C. albicans, 9/38 (23.6%) of C. glabrata, 1/2 of C. tropicalis, and 3/3 of C. guilliermondii. Six isolates (four of C. glabrata and two of C. albicans), defined as non-WT for clotrimazole, were classified as resistant to fluconazole, according to CBP from EUCAST. The isolates with elevated MIC to clotrimazole originated mostly from patients of the pediatric hematology unit, and their proportion in this population amounted to 17.8% (13 out of 73 isolates). In contrast, among strains from ambulatory patients, the highest observed MIC value was 1 mg/L (1 out of 37 isolates; 2.7%). The data obtained correlate well with those of most published studies on the in vitro susceptibility of Candida spp. to clotrimazole, which is usually very high. However, the existence of reports regarding the growing prevalence of resistant isolates has also to be noted. These results support the need for routinely checking the susceptibility of Candida clinical isolates to this imidazole derivative.

Respiratory infection caused by Chlamydophila pneumoniae in children and adolescents in the Lower Silesia Region of Poland.

OBJECTIVE: To assess the incidence of Chlamydia pneumoniae respiratory tract infection in children and adolescents in the Lower Silesia Region in Poland in 2009. MATERIAL AND METHODS: 641 throat swabs obtained from 326 girls and 315 boys, aged 11 months to 18 years, were assessed diagnostically. The patients enrolled into the study were treated on an outpatient basis due to various, non-specific respiratory ailments. The most common presenting clinical symptom of a respiratory problem was dry cough, which occurred in 295 studied subjects, followed by runny nose and cough with discharge in 176 subjects, and other minor symptoms in 35 subjects. The assessment was conducted by an indirect immunofluorescence antibody (IFA) Chlamydia Testing kit (Cellabs, Sydney, Australia). RESULTS: Overall, Chlamydia infection was detected in the respiratory tract in 43.1% (276/ 641) of the children, with no clear gender differences. Of the 295 subjects presenting with dry cough, 122 (41.4%) had positive tests for Chlamydia. Of the 176 subjects with runny nose and cough and the 35 subjects with other symptoms, 83 (47.2%) and 8 (22.9%) had positive tests for Chlamydia, respectively. In the asymptomatic children who had direct contact with a Chlamydia infected person, there were 29.6% (8/27) positively tested cases, whereas in the children presenting symptoms, the percentage of positive tests was 48.3% (29/60). CONCLUSIONS: In children living in the Lower Silesia Region of Poland, there is a substantial ∼50% rate of Chlamydia infection, transmitted via airborne droplets. The finding of Chlamydia infection should be the signal for testing other subjects from the child's closest environment.

Streptococcus agalactiae and Chlamydia trachomatis detection in women without symptoms of infection.

BACKGROUND: Chlamydia trachomatis (C. trachomatis) and Streptococcus agalactiae (GBS) may be present in the female cervical canal without any symptoms of infection. Chronic chlamydial infections lead to many serious complications and perinatal infections, while the presence of GBS is a reservoir for infections of newborns or invasive streptococcal infection in adults. OBJECTIVES: To examine healthy women for C. trachomatis without symptoms from the reproductive system, assess the frequency of asymptomatic infections, detect GBS in the cervical canal, demonstrate differences in drug susceptibility, and determine the serotype of S. agalactiae strains and correlations among the ones present in the cervical canal. MATERIAL AND METHODS: A total of 315 cervical swabs were collected for genetic and microbiological analysis for the presence of C. trachomatis and S. agalactiae. Latex and diffusion-disk methods were used to determine the serotype and susceptibility of streptococci. RESULTS: Ten out of 315 women (3.2%) were C. trachomatis-positive. Using traditional methods of microscopy, culture and serology, 42 strains (13.3% of the subjects) obtained from patients were identified as S. agalactiae and further analyzed. The most common serotypes identified were II (18/42, 42.9%), V (11/42, 26.2%) and III (10/42, 23.8%). The less common serotypes found were VII (2/10, 4.8%), and Ib (1/10, 2.4%); no Ia, IV or VII serotypes were found. All the strains were susceptible to penicillin, while 71.4% of them were susceptible to erythromycin and 81.0% were susceptible to clindamycin. Seven isolates (16.7%) were concomitantly resistant to erythromycin and clindamycin. CONCLUSIONS: Chlamydia trachomatis was confirmed in 3.2% of the respondents, and GBS was found in 13.3%, despite a lack of symptoms of infection. The incidence of C. trachomatis infections and GBS colonization in Poland is similar to those in other European countries.

Virulence factors, prevalence and potential transmission of extraintestinal pathogenic Escherichia coli isolated from different sources: recent reports.

Extraintestinal pathogenic E. coli (ExPEC) are facultative pathogens that are part of the normal human intestinal flora. The ExPEC group includes uropathogenic E. coli (UPEC), neonatal meningitis E. coli (NMEC), sepsis-associated E. coli (SEPEC), and avian pathogenic E. coli (APEC). Virulence factors (VF) related to the pathogenicity of ExPEC are numerous and have a wide range of activities, from those related to bacteria colonization to those related to virulence, including adhesins, toxins, iron acquisition factors, lipopolysaccharides, polysaccharide capsules, and invasins, which are usually encoded on pathogenicity islands (PAIs), plasmids and other mobile genetic elements. Mechanisms underlying the dynamics of ExPEC transmission and the selection of virulent clones are still poorly understood and require further research. The time shift between colonization of ExPEC and the development of infection remains problematic in the context of establishing the relation between consumption of contaminated food and the appearance of first disease symptoms. What appears to be most difficult is to prove that ExPEC strains cause disease symptoms and to examine the mechanism of transition from the asymptomatic colonization of the intestines to the spreading of the bacteria outside the digestive system. A significant problem for researchers who are trying to ascribe ExPEC transmission to food, people or the environment is to draw the distinction between colonization of ExPEC and infection. Food safety is an important challenge for public health both at the production stage and in the course of its processing and distribution. Examination of the genetic similarity of ExPEC strains will allow to determine their origin from different sources. Many levels of genotyping have been proposed in which the typing of strains, plasmids and genes is compared in order to obtain a more complete picture of this complex problem. The aim of our study was to characterize E. coli strains isolated from humans, animals and food for the presence of bacterial genes encoding virulence factors such as toxins, and iron acquisition systems (siderophores) in the context of an increasing spread of ExPEC infections.

The use of direct immunofluorescence and nested polymerase chain reaction in diagnosing perinatal infections of Chlamydia trachomatis.

BACKGROUND: Chlamydia infection is the most frequently reported infectious, sexually transmitted disease (STD). Generally, Chlamydia trachomatis (C. trachomatis) infection of neonates is the result of perinatal exposure to the mother's infected cervix. OBJECTIVES: The aim of the study was to estimate the frequency of infection caused by C. trachomatis in newborn infants. In this study of C. trachomatis perinatal infection, 107 infants born at the Wroclaw Medical University Clinic of Gynecology and Obstetrics (Poland) were tested to investigate whether C. trachomatis was present in swabs taken from the eyes and throats of children. MATERIAL AND METHODS: Each specimen was tested using the direct immunofluorescence test (DIF) and the nested polymerase chain reaction (PCR) method. RESULTS: The presence of C. trachomatis, irrespective of the origin of the swabs (ocular or from the throat), was confirmed in 62 newborns, amounting to 57.6% of the tested population. The occurrence of C. trachomatis in ocular swabs was confirmed in 35 children (32.7%). In the material taken from the throat, there were 48 newborns considered chlamydia-positive (44.9%). In the specimens taken from both the ocular and pharyngeal locations, there was a higher proportion of positive results while using the nested-PCR method in comparison to the DIF test. The specificity of the DIF method with reference to the nested-PCR was 67.9% for ocular swabs. In the material taken from the throat, the sensitivity of the DIF method with reference to the nested-PCR was 75.0% and the specificity was 62.1%. CONCLUSIONS: Because of the importance of perinatal infections, it is recommended to perform a study among a larger group of patients in order to gain more reliable results.