Evaluation of Chemical Changes in Laboratory-Induced Colistin-Resistant Klebsiella pneumoniae.

This study evaluates the electrical potential and chemical alterations in laboratory-induced colistin-resistant Klebsiella pneumoniae, as compared to the susceptible strain using spectroscopic analyses. The minimal inhibitory concentration (MIC) of colistin, ζ-potential and chemical composition analysis of K. pneumoniae strains are determined. The results obtained for the K. pneumoniaeCol-R with induced high-level colistin resistance (MIC = 16.0 ± 0.0 mg/L) are compared with the K. pneumoniaeCol-S strain susceptible to colistin (MIC = 0.25 ± 0.0 mg/L). Fourier transform infrared (FTIR) and Raman spectroscopic studies revealed differences in bacterial cell wall structures and lipopolysaccharide (LPS) of K. pneumoniaeCol-R and K. pneumoniaeCol-S strains. In the beginning, we assumed that the obtained results could relate to a negative charge of the bacterial surface and different electrostatic interactions with cationic antibiotic molecules, reducing the affinity of colistin and leading to its lower penetration into K. pneumoniaeCol-R cell. However, no significant differences in the ζ-potential between the K. pneumoniaeCol-R and K. pneumoniaeCol-S strains are noticed. In conclusion, this mechanism is most probably associated with recognisable changes in the chemical composition of the K. pneumoniaeCol-R cell wall (especially in LPS) when compared to the susceptible strain.

Synergistic effect of fennel essential oil and hydrogen peroxide on bacterial biofilm.

INTRODUCTION: Staphylococcal biofilm formation significantly challenges wound management. The causes of difficult-to-treat wounds are not only methicillin-resistant staphylococci, but also methicillin-sensitive strains with different patterns of resistance. Bacterial biofilm significantly limits the access and activity of antimicrobials used in dermatological infections. AIM: To evaluate the synergistic effect of fennel essential oil (FEO) and H2O2 on biofilm formation by Staphylococcus aureus (MSSA and MRSA) reference strains. MATERIAL AND METHODS: Minimum inhibitory concentration (MIC) values were determined for FEO and H2O2 against S. aureus reference strains by the broth microdilution method. The combined effects of the FEO and H2O2 were calculated and expressed in terms of a fractional inhibitory concentration index (FICI) using the checkerboard method. The FEO composition was analyzed by the GC-MS method. The data were analysed by one-way ANOVA. RESULTS: Decreased MIC values for FEO combined with H2O2 were observed in comparison to FEO itself. The combinations of FEO and H2O2 determined synergistic effects on all S. aureus reference strains. Subinhibitory concentration of FEO alone and in combination with 0.5 MIC of H2O2 significantly decreased the production of biofilm biomass in S. aureus strains and reduced the metabolic activity of attached cells. CONCLUSIONS: Combination of fennel essential oil containing nearly 80% trans-anethole and H2O2 represents a potential for further basic and applied research on wound management.

The effect of fennel essential oil and trans-anethole on antibacterial activity of mupirocin against Staphylococcus aureus isolated from asymptomatic carriers.

INTRODUCTION: Staphylococcus aureus constitutes the most pathogenic species within the staphylococcal genus. Humans remain the major reservoirs of this pathogen which colonizes mostly anterior nares of healthy individuals. AIM: To investigate the effect of fennel essential oil (FEO) and trans-anethole (tA) on antibacterial activity of mupirocin (MUP) against S. aureus strains isolated from asymptomatic carriers. MATERIAL AND METHODS: The content of the FEO was analysed with use of the GC-MS method. The research done on 43 S. aureus isolates with different resistance patterns, obtained from nasal vestibule. Antibacterial activity of MUP in combination with FEO or tA was examined using the agar dilution method and E-test method. The data analysis was done with the Pearson's χ2 test. RESULTS: The chemical composition of FEO was consistent with the European Pharmacopoeia (EP) for the main constituent - tA (77.9%) according to the EP recommendations. Macrolide-lincosamide-streptogramin B resistance phenotype was prevalent among 39.5% of S. aureus isolates. FEO concentrations of 2.0% and 2.5% revealed antibacterial activity against 76.7% of isolates, whereas tA inhibited S. aureus growth at concentrations > 4.0%. The MIC values for MUP combined with FEO as well as for MUP combined with tA were < 0.064 µg/ml for 79.1% and 86.0% of S. aureus isolates, respectively. CONCLUSIONS: Our experiment revealed FEO and tA influence on MUP effectiveness. The combination of MUP with FEO as well as MUP with tA are worth considering to implement in S. aureus eradication procedures. These findings will be useful in designing efficient antistaphylococcal agents which can limit the emergence of antibiotic resistance.

Epidemiology of infections in kidney transplant recipients - data miner's approach.

Infections remain a frequent complication following organ transplantation. Agents present within the general population remain common in recurrent infections among renal transplant recipients. Data mining methodology has become a promising source of information about patterns in the organ transplant recipient population. The aim of the study was to use data mining to describe the factors influencing single and recurrent infections in kidney transplant recipients. A group of 159 recipients who underwent kidney transplantation between 2005 and 2008 was analysed. RapidMiner and Statistica softwares were used to create decision tree models based on CART Quinlan and C&RT algorithms. There were 171 microbiologically confirmed episodes among 67 recipients (41%), and 191 separate species isolations were performed. Over 50% of the infected patients underwent two or more infectious episodes. Two classification decision tree models were created. The following features were enabled to differentiate the groups with single or recurrent infections: the duration of cold ischaemia, the post-transplant hospitalization period, the cause of chronic kidney disease and pathogens. The post-transplant hospitalization period and the length of cold ischaemia appear to be the principal parameters differentiating the subpopulations analysed. These coexisting factors, connected with recurrent infections in kidney transplant recipients, resemble a network which requires an advanced analysis to support the traditional statistics.

[Analysis of screening tests for Streptococcus agalactiae in pregnant women from the West Pomeranian region]. / Analiza badan przesiewowych w kierunku Streptococcus agalactiae u kobiet w ciazy z regionu Pomorza Zachodniego.

OBJECTIVE: The aim of the study was to determine the degree of colonization Streptococcus agalactiae (GBS--Group B Streptococcus) in women at 35.-37. weeks of pregnancy and to evaluate drug susceptibility of the isolated strains. MATERIAL AND METHODS: We analyzed the results of 1111 tests for GBS colonization performed between 2010-2013 in pregnant women (aged 16-40) from the West Pomeranian region. Swabs were taken from the vagina and the anus of the study subjects at 35.-37. weeks of pregnancy Materials were cultured on Granada Agar and in selective Todd-Hewitt broth, which was next cultured on Granada Agar The degree of GBS colonization was determined by the semi-quantitative method on solid media. The strains were tested for susceptibility to penicillin, erythromycin and clindamycin by disc diffusion method according to the EUCAST standards. RESULTS: Positive cultures for S. agalactiae were found in 22.5% of the pregnant women. The highest (25.4%) and the lowest (15.9%) rates of GBS colonization were observed in the age groups of 31-35 and 16-20 years, respectively Massive GBS colonization was detected in 68.4% of pregnant subjects, with the highest and the lowest rates in the age groups of 31-35 and 16-20 years, (75.3% and 50.0%, respectively). All isolated GBS strains were sensitive to penicillin. Macrolide, lincosamide and streptogramin B resistance (MLSB) was found in 28% of the isolates, resistance only to erythromycin (phenotype M) in 2% of the strains. There were no significant differences in the degree of GBS colonization and drug sensitivity of GBS strains versus the year of our examination. CONCLUSIONS: Monitoring for GBS colonization in the last weeks of pregnancy seems to be necessary for effective prevention of S. agalactiae infections.

Superantigen gene profiles, genetic relatedness and biological activity of exosecretions of Staphylococcus aureus isolates obtained from milk of cows with clinical mastitis.

This study evaluated the superantigen gene profiles, genetic relatedness and biological activity of exosecretions of 50 Staphylococcus aureus isolates obtained from milk of cows with clinical mastitis. Genomic relatedness of S. aureus was determined by pulsed field gel electrophoresis analysis of macro-restricted chromosomes. The presence of genes encoding superantigens was confirmed by multiplex PCR. To study the biological activity of S. aureus exosecretions, the supernatants from bacterial liquid cultures were classified into three groups: those with leukotoxin­like properties, those with superantigen­like properties and those with no particular activity on leukocytes cultured in vitro. It was shown that all analyzed bacterial isolates belonged to the same clonal type and harbored the same combination of superantigen genes, namely sed, selj and ser. However, 22% of all isolates produced factors with superantigen­like and 48% of them with leukotoxin­like activities. Finally, although there were no detectable genetic differences between the analyzed bacterial isolates, the virulence factors secreted by them differed considerably.

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.

Endogenous or exogenous origin of vaginal candidiasis in Polish women?

Vaginal candidiasis is a common problem of clinical practice. Many studies have been conducted to explain its origin but only a few have included Polish women. The aim of the study was to determine the prevalence and similarity of oral, anal and vaginal Candida albicans strains isolated from Polish women with vaginal candidiasis. The study involved 20 from 37 recruited women. Swab samples were collected from their vagina, anus, and oral cavity at two-month intervals. All the women were treated with nystatin. Yeast were recovered and identified by the germ-tube test, API /Vitek system, typed by API ZYM and RAPD-PCR. Chi-square test was used to analyze the data. A total of 170 Candida albicans isolates were recovered from 180 samples collected 3 times from 3 sites of 20 women. Positive yeast vaginal cultures were found in all patients before administration of nystatin. Vaginal yeast recovery rate was decreased statistically significant in both follow-up visits (p= 0.001; p= 0.003). The same and different genotypes/biotypes were found concomitantly in a few body sites and/ or repeatedly at time interval from the same body site. The results support the concept of dynamic exchange of yeast within one woman and endogenous or exogenous origin of vaginal candidiasis.

Bacterial flora in blood samples collected during an autopsy for routine testing of ethanol concentration / Flora bakteryjna w próbkach krwi rutynowo pobranych do badan na zawartosc etanolu podczas autopsji.

Blood samples collected during autopsy for routine ethanol testing, preserved with sodium fluoride were subjected to the following microbiological tests: microscopic evaluation, cultures on differentiating proliferating media and identification of isolated strains. It was found that sodium fluoride did not entirely inhibit bacterial growth. The majority of the isolated bacteria were Gram-negative rods, with E. coli as the most frequent strains.

Similarity Analysis of Klebsiella pneumoniae Producing Carbapenemases Isolated from UTI and Other Infections.

Klebsiella pneumoniae is an important opportunistic pathogen responsible for severe infections, mainly urinary tract infections (UTIs) and pneumonia. Hospital epidemic infections caused by multiresistant strains of carbapenemase-producing K. pneumoniae are the most concerning. NDM-producing strains are resistant to a wide range of antibiotics and have become the most significant threat. Determining the natural reservoirs and routes of infections is essential to end hospital outbreaks. Understanding the relatedness of K. pneumoniae strains is essential to determine the range and nature of the infection. The study compared phylogenetic relatedness between multiresistant K. pneumoniae strains isolated from hospitalized patients. Susceptibility to drugs and mechanisms of resistance were confirmed using phenotypic methods. PFGE was used to analyze the relatedness between strains. We analyzed 69 K. pneumoniae strains from various healthcare units. The isolates were mainly identified from urine. Strains were resistant to ß-lactam antibiotics with ß-lactamase inhibitors, cephalosporins, and quinolones. Their susceptibility to aminoglycosides and carbapenem antibiotics was diverse. Most of the isolated strains produced New Delhi metallo-ß-lactamase (NDM). Although K. pneumoniae strains were classified into several genotype clusters, closely related isolates were confirmed in the same hospital's wards, and in two hospitals in the same province.

Improved RAPD Method for Candida parapsilosis Fingerprinting.

Recently, methods based on the analysis of arbitrarily amplified target sites of genome microorganisms have been extensively applied in microbiological studies, and especially in epidemiological studies. The range of their application is limited by problems with discrimination and reproducibility resulting from a lack of standardized and reliable methods of optimization. The aim of this study was to obtain optimal parameters of the Random Amplified Polymorphic DNA (RAPD) reaction by using an orthogonal array as per the Taguchi and Wu protocol, modified by Cobb and Clark for Candida parapsilosis isolates. High Simpson's index values and low Dice coefficients obtained in this study indicated a high level of interspecies DNA polymorphism between C. parapsilosis strains, and the optimized RAPD method proved useful in the microbiological and epidemiological study.

[Endophthalmitis in course of candidosis--a case report]. / Zapalenie wnetrza galki ocznej w przebiegu kandydozy--opis przypadku.

PURPOSE: Description of a rare case of bilateral fungal endophthalmitis in a patient and the associated diagnostic and therapeutic difficulties. MATERIAL AND METHODS: Patient 28 years old was diagnosed because of bilateral deterioration in endophthalmitis. Therefore, the diagnostic possibilities were run down and material taken from the vitreous chamber were handed to determine the Candida spp. antigen using Elisa test, standardized for serum and cerebrospinal fluid. Combination therapy including drugs and surgery were performed. RESULTS: Ophthalmoscopy OP/OL showed the presence of "clusters of cotton" in vitreous body characteristic for ocular candidosis. Targeted treatment for Candida spp. with voriconazole were based on a very high concentration of mannan antigen in the resulting of the test. The final diagnosis was established after microbiological examination of material taken during vitrectomy. CONCLUSIONS: High level of mannan antigen Candida spp 4259.83 in vitreous body may indicate a fungal endophthalmitis. fungal endophthalmitis, ocular candidosis, endogenic infection of the eye.

Epidemiological Analysis of Extended-Spectrum ß-Lactamase-Producing Klebsiella pneumoniae Outbreak in a Neonatal Clinic in Poland.

Klebsiella pneumoniae is one of the most common etiological agents isolated from epidemic outbreaks in neonatal wards. We describe how an extended-spectrum ß-lactamase-producing K. pneumoniae (ESBL-KP) outbreak in a neonatal ward was extinguished. During the outbreak, which lasted over two months, 26 neonates were tested for K. pneumoniae, and 42 environmental swabs were taken. Drug susceptibility was determined for the isolated strains, and their virulence and phylogenetic similarity were checked. ESBL-KP colonization was confirmed in 18 neonates, and six were also confirmed to be infected. All strains isolated from patients represented one clonal type, K. pneumoniae. One strain isolated from an environmental source was determined to be a unique pulsed-field gel electrophoresis pattern. Gestational age and Apgar score were assessed as statistically significant for neonates with ESBL-KP infection. The epidemiological measures taken have been successful, and no further cases appeared. Immediate tightening of hospital hygiene rules, screening of all hospitalized neonates, and cohorting ESBL-KP-positive patients proved effective in controlling and ending the outbreak. The lack of ESBL-KP in the environment suggests that the outbreak was transmitted by colonized hospital staff. This theory could be confirmed by introducing mandatory screening for medical personnel.

Genetic Diversity of Candida spp. Isolates Colonizing Twins and Their Family Members.

A wide range of options for studying Candida species are available through genetic methods. Twins, particularly monozygotic ones and their families may be fitting subjects for studying those microorganisms. The question is: How specific can yeast flora be in an individual? The study aimed to analyze the strain relatedness among commensal yeasts isolated from various parts of the bodies of healthy people and to compare correlations between the genotypes of the isolates. Yeasts were isolated from 63 twins and their family members (n = 25) from the oral cavity, anus, interdigital space and navel. After species identification, Candida albicans (n = 139), C. parapsilosis (n = 39), C. guilliermondii (n = 25), C. dubliniensis (n = 11) and C. krusei (n = 9) isolates were analyzed using the random amplified polymorphic DNA polymerase chain reaction (RAPD-PCR) optimization method. The similarities between the strains were calculated based on the Dice (Sab) coefficient and are displayed graphically as dendrograms. Using cluster analysis, the following relatedness was distinguished: 13 genotypes and three unique (Un) patterns among C. albicans; 10 genotypes and four Un patterns among C. parapsilosis; three genotypes and one Un pattern among C. guilliermondii and C. dubliniensis; and three genotypes among C. krusei isolates. The presence of identical, similar or both genotypes among the strains isolated from family members shows the transmission of yeasts between ontocenoses in the same person and between individuals. The similarity between the genotypes of C. albicans, C. guilliermondii, C. dubliniensis and C. krusei was more remarkable than between the genotypes of C. parapsilosis in the strains isolated from ontocenoses of the same individual and their family members. The degrees of genetic similarity between Candida spp. strains isolated from monozygotic twins and those obtained from their relatives did not differ.

Association of recurrent furunculosis with Panton-Valentine leukocidin and the genetic background of Staphylococcus aureus.

Staphylococcus aureus is a major cause of skin and soft tissue infections, such as furuncles, carbuncles, and abscesses, but it also frequently colonizes the human skin and mucosa without causing clinical symptoms. Panton-Valentine leukocidin (PVL) is a pore-forming toxin that has been associated with soft tissue infections and necrotizing pneumonia. We have compared the genotypes, virulence gene repertoires, and phage patterns of 74 furunculosis isolates with those of 108 control strains from healthy nasal carriers. The large majority of furunculosis strains were methicillin sensitive. Clonal cluster (CC) 121 (CC121) and CC22 accounted for 70% of the furunculosis strains but for only 8% of the nasal isolates. The PVL-encoding genes luk-PV were detected in 85% of furunculosis strains, while their prevalence among colonizing S. aureus strains was below 1%. luk-PV genes were distributed over several lineages (CCs 5, 8, 22, 30, and 121 and sequence type 59). Even within the same lineages, luk-PV-positive phages characterized furunculosis strains, while their luk-PV-negative variants were frequent among nasal strains. The very tight epidemiological linkage between luk-PV and furunculosis, which could be separated from the genetic background of the S. aureus strain as well as from the gene makeup of the luk-PV-transducing phage, lends support to the notion of an important role for PVL in human furunculosis. These results make a case for the determination of luk-PV in recurrent soft tissue infections with methicillin-sensitive as well as methicillin-resistant S. aureus.

Associations between HLA molecules and ophthalmologic diseases.

The aim of this review was to analyze associations between HLA (human leukocyte antigens) alleles described thus far and an array of ophthalmologic disorders. Highly polymorphic HLA molecules play a crucial role in immunological response to various pathogens. Due to environmental pressures exerted mostly by infectious factors in the past, population frequencies of particular alleles differ greatly and modulate immunological response in various diseases. Associations between HLA alleles and over 500 pathologies, mainly autoimmune, infective and inflammatory diseases, have been previously described. In the course of certain HLA-related diseases described so far, eye manifestations are present. In this paper we review the structure, function and linkage between HLA antigens, ophthalmologic diseases and systemic disorders with eye involvement.

[Is autosomal dominant polycystic kidney disease associated with asymptomatic bacteriuria?]. / Czy u chorych z autosomalna dominujaca wielotorbielowatoscia nerek wystepuje bakteriomocz bezobjawowy?

UNLABELLED: Urinary tract infections (UTIs) are a common complication in patients with autosomal dominant polycystic kidney disease (ADPKD). Asymptomatic bacteriuria (AB) is a factor predisposing to UTI in other populations. The aim of the study was to determine whether AB is more frequent in a group of ADPKD patients with normal kidney function and no diabetes than in a healthy control group. MATERIAL AND METHODS: A group of 49 ADPKD patients (19 men and 30 women) with normal kidney function (creatinine level < 1.35 mg/dl) and no diabetes, with an average age of 35.9 +/- 11.1 years was compared with a group of 50 healthy controls (22 men, 28 women) with similar age (36.7 +/- 9.2 years). All subject were evaluated using medical history and physical examination, urine culture, urinalysis (biochemical and morphological), kidney ultrasonography, oral glucose tolerance test (with 75 g of glucose) and serum creatinine testing. RESULTS: UTIs were significantly more frequent in medical history of ADPKD patients than in control group (26% vs. 0%, p < 0.001). Asymptomatic bacteriuria was found in 2% of ADPKD patients and in 4% of control group (p = 0.69). The presence of protein in urinalysis was observed in 6% of ADPKD and in none of the control patients. Other urine measurements like pH, specific gravity, and morphological examination were normal and did not substantially differ between groups. The kidneys of ADPKD patients were significantly longer than in control group (p < 0.001). CONCLUSIONS: Asymptomatic bacteriuria is not present more frequently in ADPKD patients with normal kidney function and no diabetes, than in healthy people.

The Effect of Subinhibitory Concentrations of trans-Anethole on Antibacterial and Antibiofilm Activity of Mupirocin Against Mupirocin-Resistant Staphylococcus aureus Strains.

Aim: The aim of this study was to evaluate the effect of subinhibitory concentrations of trans-anethole on antibacterial and antibiofilm properties of mupirocin against mupirocin-resistant Staphylococcus aureus strains. Methods: Following parameters were examined: isolates susceptibility to antibiotics, minimum inhibitory concentration (MIC) of trans-anethole, antibacterial activity of mupirocin/trans-anethole combination, detection of ileS2 gene, genotypic relativity of isolates using pulsed-field gel electrophoresis method, and the influence of mupirocin/trans-anethole combination on S. aureus biofilm formation. Results: Our study revealed that trans-anethole combined with mupirocin increased the growth inhibition zone diameter around the mupirocin disk, independently on S. aureus strains susceptibility to this antibiotic. Moreover, combination of subinhibitory (MIC50) concentration of mupirocin and trans-anethole significantly decreased biofilm biomass. Conclusions: trans-Anethole appeared efficient in increasing susceptibility to mupirocin and decreasing biofilm formation in S. aureus strains used in this study. Reduction of biofilm formation can potentially protect against S. aureus recolonization. Moreover, use of trans-anethole in combination with mupirocin can increase the mupirocin activity against methicillin-resistant and mupirocin-resistant S. aureus strains.

[Anaerobic bacteria of periodontal pockets in course of periodontitis and premature labor]. / Flora beztlenowa kieszonek przyzebnych w zapaleniu przyzebia a poród przedwczesny.

The aim of the study is was to evaluate anaerobic periodontal mikrobes in 120 postpartum mothers. Group I consisted of mothers with a birth weight of less than 2,500g and gestational age < 37 weeks. Group II included mothers with normal birth weight infants. All women in both of groups were subjected to a full-mouth periodontal examination to determine a periodontal status. The microbial investigation for anaerobic bacteria of deepest periodontal pockets was performed in 35 cases of periodontits. A significantly higher incidence of preterm low birth weight cases in patiens with periodontitis was documented. In addition higher variety of anaerobic bacteria of periodontal pockets in mothers with preterm low birth weight infants comparison to control group was observed.

[Colonization (infection) of the respiratory tract in outpatients in 2000-2005 years]. / Kolonizacja (zakazenie) dróg oddechowych u chorych leczonych ambulatoryjnie w latach 2000-2005.

UNLABELLED: Infections of the respiratory tract are one of the main causes of family doctor visiting. A variety of etiological factors (mostly viruses, typical and non typical bacteria) causes that the diagnosis of these infections is rarely made in outpatient practice (usually these are nose and throat smears); additionally the carrier state of typical bacteria in the respiratory tract impedes the interpretation of microbiological results. THE AIM OF THE STUDY was to assess the incidence of potential bacterial etiological factors of respiratory tract infections in outpatients in the years 2000-2005. MATERIAL AND METHODS: The 3270 microbiological results obtained from patients at the age of between 1 month and 88 years old with chronic and acute symptoms of respiratory tract infections were analyzed. RESULTS: The positive results of bacteria culture indicating the possible bacterial etiological agent of infection were found from 1051 patients (34.4%), mostly in autumn - spring time. Most often were isolated: H. influenzae - 28.8%, S. pneumoniae - 22.1% and S. aureus - 22.1%, in less percentage M. catarrhalis - 14.1% and S. pyogenes - 13.1. Positive bacteria cultures were received most often from ear secretion- 66.8% (P. aeruginosa, S. aureus), from nose-41.2% (S. pneumoniae, H. influenzae), sputum - 34.9% (S. aureus), throat - 24.3% (H. influenzae, S. pyogenes). CONCLUSIONS: It has been confirmed that predominant participation of viruses in respiratory system infections is observed and also seasonal character of their bacterial nature occurrence (35%). Most often were isolated: H. influenzae, S. pneumoniae, S. aureus, also M. catarrhalis. On the ground of carrier state of these bacteria in nasopharynx it is a clinician's decision to recognize the bacteria as the etiological agent of infection and possible use of antibiotic treatment.