Search

Objective: to evaluate and compare the qualitative and quantitative composition of the intestinal microbiota in patients with malignant neoplasms of various localizations. Material and Methods. The study included patients who received different types of treatment in N.N. Blokhin Oncology Research Center, Moscow, Russia in 2023 for gastric cancer, including cardioesophageal adenocarcinoma (group 1), esophageal squamous cell carcinoma (group 2) and metastatic or locally advanced melanoma of the skin (group 3). All patients had to have morphologic verification of the diagnosis at the time of inclusion, be over 18 years old, have an ECOG performance status of ≤1, and have no evidence of intestinal infection, as well as not take antibiotics within 28 days prior to entry into the study. Stool samples were collected during patients’ hospitalization. The quantitative and qualitative composition of microorganisms of 17 taxonomic groups was evaluated. Microorganisms were cultured according to standard microbiological methods, taking into account the growth conditions of a particular group of microorganisms. Species identification of microbial isolates was obtained by matrix-assisted laser desorption/ionization-time-of-flight mass spectrometry (MALDI-TOF) and MALDI Biotyper v.3.0 software (Bruker daltonics, Germany). Descriptive statistics methods from the SPSS Statistics, v.27 software package were used. To quantitatively describe the species diversity of the gut microbiota, calculations were performed using the Margalef species richness index (d) and Shannon’s (H) diversity index. The criterion of uniformity of microbial species distribution according to their abundance in the population community was evaluated using the Pielow index (E). The Hutcheson’s T-criterion was used to test the significance of differences between sample sets of Shannon index values and to obtain statistically correct estimates of differences (p≤0.05). Results. A total of 63 samples of biological material (feces) were investigated. A change in the quantitative composition of intestinal microbiota in all study groups was found, which may have a negative impact on the general condition of the patient and the effectiveness of antitumor treatment. The increase in the proportion of Proteobacteria (Enterobacterales) can be considered as a risk factor for the development of infectious complications caused by Gram-negative microorganisms. The analysis of factors influencing the taxonomic diversity of intestinal microbiota revealed no significant differences in the composition of intestinal microbiota between the groups of patients with malignant tumors of different nosological forms (p>0.05).

Objective. To conduct a systematic analysis of data on the results of studies published in scientific journals on the pro-carcinogenic and anticarcinogenic role of microbiota, as well as on the therapeutic potential of microorganisms in oncogenesis.Material and Methods. The articles were searched using the Web of Science, Scopus, PubMed, Medline, and eLIBRARY databases. More than 150 sources dedicated to the study of the carcinogenic function of the microbiota and the possible influence of its species and quantitative composition on the efficacy and toxicity of antitumor therapy were found. Data from 71 articles were included in the review.Results. The relationship between the gut microbiota and cancer is multifactorial and bilateral: pro-carcinogenic on the one hand and anti-carcinogenic on the other hand. Microorganisms can induce tumor growth and cancer development through DNA damage and induction of mutagenesis, trigger oncogenic signals, disruption of barrier function, as well as immune response system disruption. Depletion of microbiota, the development of dysbiosis and induction of chronic inflammatory state are negative factors in the development of cancer. The anticancer effect of microorganisms is presumably based on the production of tumor-suppressive metabolites that function through multiple immune reactions. Maintenance of barrier function, competitive exclusion of pathogenic bacteria, and direct action on immune cells to prevent inflammation are also important protective factors. The presence of intratumor microorganisms in various tumors has been noted. Changes in species and quantitative composition of cancer patients’ microbiota are influenced by diet, taking antibacterial drugs, chemo-, immuno- and radiation therapy. In turn, the microbiota can affect the ongoing treatment. Numerous studies on the influence of the gut microbiota on the efficacy of immunotherapy, particularly in disseminated melanoma, have been conducted. It has been suggested that primary resistance to immunotherapy may be related to the abnormal composition of the gut microbiota. The level of gut microfora composition diversity and the number of Faecalibacterium or Bacteroidales in the fecal microbiota have been suggested to be the predictor of response to anti-PD-1 therapy. To change the composition and activity of the gut microbiota, several therapeutic methods, such as the administration of prebiotics, probiotics, synbiotics, postbiotics, fecal microbiota transplantation, as well as the change in the microbiota composition through a specific diet, are available.

Introduction. Interactions between the 2 microbiota components – bacteria and fungi – are of interest as diagnostic and prognostic markers in selection of treatment tactics for oncological patients.Aim. To study microbiota of the oral cavity in patients with primary squamous cell carcinoma of the oropharyngeal area before and after surgical intervention to find biomarkers for rational selection of antifungal drugs.Materials and methods. At the Surgical Department of Head and Neck Tumors of the N. N. Blokhin National Research Center of Oncology, three-component study was performed: investigations of spectrum of Candida spp. isolates, Candida spp. strains’ resistance to antifungals, and oral washes in primary patients before and after surgery. mALDI-Tof microflex LT (Biotyper, Bruker Daltonics, germany) was used for strain identification; Sensititre Yeast ONE, YO10 (Trek Diagnostic System, united kingdom) plates were used for determination of minimal inhibiting concentrations of anti fungals. values of minimal inhibiting concentrations were evaluated based on the European Committee on Antimicrobial Susceptibility Testing (EuCAST) criteria (version 10.0).Results. four-year observation of patients at the surgical department of head and neck tumors of the N. N. Blokhin National Research Center of Oncology showed that the most common species of Candida is C. albicans (73.5 % of cases). Candida spp. resistance to antifungals was detected only for fluconazole (9.3 % of cases) and micafungin (8.0 % of cases), mostly among C. albicans strains. In 31.8 % of primary patients, oral washes prior to surgery showed growth of Candida spp. (probably, tissue colonization). After surgical intervention, Candida spp. growth was detected in 36.4 % of cases, only 1 of which was diagnosed as invasive mycosis. In 54.5 % of cases before and in 72.7 % of cases after surgery, gram-negative rods were detected. After surgical intervention, percentage of enterobacteria and non-fermenters significantly increased: 59.1 % versus 27.3 % (p

Relevance. The global trend of rapid increase in resistance to antifungal drugs due to multiple factors, dictates the need for continuous monitoring of taxonomic structure and susceptibility of nosocomial pathogens, causing invasive fungal infections, for permanent correction of the optimal prevention and treatment strategies.Purpose: to determine antifungal susceptibility of the main yeast pathogens in candidemia in cancer patients, as well as to determine resistance genes and pathogenic factor genes.Material and Methods. Eighty-two strains of Candida spp. isolated from blood of cancer patients from 2015 to 2021 were analyzed. Minimum inhibitory concentrations of fuconazole, voriconazole, posaconazole, anidulafungin and micafungin were determined by a gradient method (E-test, BioMerieux, France). The EUCAST and CLSI criteria were used for MIC value assessment. The genes, associated with pathogenicity factors, and resistance to antifungal drugs were identifed.Results. Our study results based on EUCAST 2020, v.10.0 criteria showed that triazoles, especially fuconazole, were the least effective drugs in empirical therapy for invasive candidiasis (including candidemia). Resistance of Candida spp. fuconazole was superior to that of voriconazole (47.2 % vs 23.2 %, respectively, p0.05). The ERG11 and FKS1 genes associated with resistance to antifungal drugs were detected in 28.6 % of Candida spp. strains. The ERG11 gene was detected in 8.6 % of cases, exclusively in Candida albicans strains. The FKS1 gene was identifed in 20.0 % of strains (85.7 % of them were C. parapsilosis, 7.1 % each were C. tropicalis and C. glabrata). Pathogenic factor genes were identifed in 78.6 % of C. albicans and in 79.1 % of C. parapsilosis strains.Conclusion. Molecular genetic methods for the detection of Candida spp strains carrying resistance genes to antifungal drugs, and the determination of pathogenicity factors are promising trends in searching for biomarkers. They facilitate interpretation of results of microbiological study to assess the ability of Candida spp. strains to develop invasive mycoses.

Introduction. The associative role of the bacterial factor in the development of both primary malignant tumors of the oral mucosa and relapses is being actively discussed today. In the article published earlier, we have already described the possible mechanisms of action of periodontopathogenic microflora and its connection with the development of squamous cell carcinoma of the oral mucosa through cell proliferation, intracellular accumulation of pathogen, DNA replication and affect the signaling pathways of MARK (mitogen-activated protein kinase).Objective – to analyze the impact of periodontal pathogens on the risk of oral squamous cell carcinoma and its recurrence, as well as to evaluate the role of polymerase chain reaction and bacterial culture in the diagnosis of squamous cell carcinoma.Materials and methods. This study included 35 patients with stage Т3–4 squamous cell carcinoma, whose tumor tissue samples were tested for periodontal pathogens using culture and PCR. We analyzed 5 paraffin-embedded and 30 frozen tissue blocks from newly diagnosed (n = 15) and re-treatment (n = 15) patients.Results. We found that PCR was more sensitive than culture for the detection of possible etiological agents and predictors of squamous cell carcinoma (including Porphyromonas gingivalis, Tannerella forsythia, and Treponema denticola) (р

The purpose of the study: to compare the activity of vancomycin, teicoplanin and linezolid and to determine their place in the current treatment of nosocomial infections caused by gram-positive microflora.Material and Methods. 640 gram-positive microorganisms (S. aureus, E. faecium, E. faecalis) isolated in 2018 from various pathological materials from cancer patients treated at N.N. Blokhin National Medical Research Center of Oncology were studied. Literature data from 1982 to 2019, concerning efficacy of glycopeptides (vancomycin, teicoplanin) and linezolid against these pathogens were analyzed.Results. Data analysis showed that percentage of methicillin-resistant Staphylococcus aureus (MRSA) was 89 % and percentage of vancomycinresistant enterococci (VRE) was 5.1 % among Enterococcus faecalis and 16.4 % among Enterococcus faecium. The susceptibility of the studied gram-positive microorganisms to teicoplanin, vancomycin and linezolid ranged from 83.3 to 98.8 % (p>0.5). In general, teicoplanin, vancomycin, and linezolid had equally high microbiological activity against nosocomial strains of S. aureus and Enterococcus spp. Also, according to the literature data, a comparative assessment of the clinical effectiveness and cost-effectiveness of glycopeptides and linezolid was assessed.Conclusion. Vancomycin and teicoplanin are still the main drugs for the treatment of various infections caused by resistant gram-positive microflora. However, teicoplanin, with an efficacy equal to that of vancomycin, has a number of significant advantages over the latter: better tolerability, lower frequency of adverse reactions, and pharmacokinetic features that make it possible to use it once a day both intravenously and intramuscularly. Both drugs, along with linezolid, can be used to treat infections caused by gram-positive microorganisms in cancer patients.

Introduction. Penile cancer (pc) is a rare cancer. The standardized incidence rate of pc in russia is 0.82 cases per 100,000 males. On average, 58 % of patients (20–96 %) with pc have a local infection process: tumor decay, the presence of erosion, tumor ulceration, inflammatory changes in regional lymph nodes, etc. During hospitalization nosocomial pathogens may be possible causes of infection in ulcerative lesions.The aim of the study was to present the results of the treatment of tumor ulcer in a patient with penile cancer infected with multiresistant acinetobacter baumannii and klebsiella pneumoniae.Material and methods. We present a clinical observation of 54-year-old patient diagnosed with penile cancer pt4n3m0, with ulceration of the tumor, localized at the root of the penis and ulceration of metastatic lymph nodes in the left inguinal region and subsequent infection with highly resistant nosocomial microorganisms.Results. The patient received 6 courses of paclitaxel, ifosfamide and cisplatin with clinical effect, such as significant reduction of the tumor and therapeutic pathomorphosis of 3-rd degree. Then ileo-inguinal lymphadenectomy was performed on the left. A few months later the tumor continued to grow in the left groin area. During the 2nd line of chemotherapy (cisplatin, docetaxel and capecitabine), the patient had grade iii–iv neutropenia, febrile neutropenia. High fever and localized infection in the area of tumor ulceration with multiresistant hospital microorganisms was detected. Combined antibiotic therapy had temporary effect. After isolation of multiresistant carbapenemresistant k. Pneumoniae from the ulcer, the patient was prescribed ceftazidim/avibactam 2.5 g 3 times a day. Clinical effect, such as defervescence and significant reduction of the ulceration zone was seen subsequently.Conclusion. Etiotropic antibacterial therapy of the infected tumor ulcer resulted in a significant reduction in the manifestation of the infection process, allowing antitumor therapy to be continued, as well as surgery to be performed.

Introduction. Currently, there is no global consensus regarding the management of breast cancer patients with implant-associated infections. Some studies clearly recommend their removal and surgical debridement with consecutive antimicrobial treatment, while others prefer long-term antibacterial therapy (at least 1 month) with the effectiveness of such conservative approach of 36–73 %.Case description. A 43-year-old patient suffering from brca1-positive right breast cancer t2n0m0 (invasive carcinoma of non-specific type g3, er – 8, pgr – 0, her-2/neu – 0, ki67 (%) – less than 20 %), underwent radical skin-preserving mastectomy on the right with simultaneous implant reconstruction and preventive subcutaneous mastectomy on the left with simultaneous implant reconstruction. Peri-implant infection in the left breast was observed on the 21st day after surgery.Results. The patient received empirical therapy with cefepim. Microbiological examination of the punctate revealed the causative agent of infection – methicillin-resistant staphylococcus aureus (mrsa) (1×105cfu/ml). Daptomycin 6 mg/kg/day was added to therapy. After 8 weeks, the patient received oral moxifloxacin 400 once daily, for another 3 weeks. A complete response was achieved. The patient has no signs of infection for 3 years.Conclusion. Long-term etiotropic antibacterial therapy with daptomycin followed by oral moxifloxacin resulted in a stable clinical effect.

The study objective is to evaluate the effect of periodontal microorganisms on development of squamous-cell carcinoma of the oral mucosa and the risk of its recurrence.Materials and methods. Microbiological study of biomaterials from 150 patients was performed. The study group included 100 patients with T3–T4 squamous-cell carcinoma of the oral mucosa and was subdivided into two subgroups with 50 patients in each. The control group included 50 patients.Results. Analysis of the results obtained in the subgroup of primary patients showed the following trends: in 2 (50 %) of 4 patients with Fusobacterium spp., recurrence of the main disease was observed as well as a case of distant metastasis into the bones. Among 35 patients with Prevotella spp. in the biomaterials, in 16 (45.7 %) recurrence of the tumor was observed. Among 10 patients with Veillonella spp., recurrence was observed in 20 %. The most common aerobic microorganism was Streptococcus spр. Among patients who underwent treatment at the N.N. Blokhin National Medical Research Center of Oncology, recurrence was diagnosed in 28.5 %, distant metastases in 4.7 %. In the subgroup of repeat patients, the following trends were observed: among 27 patients with Fusobacterium spp., recurrence of the main disease was observed in 63 %. Among 26 patients with Prevotella spp. in the biomaterial, in 11 (42.3 %) local recurrence was observed. Among 24 patients with Veillonella spp., recurrence developed in 33.3 %. The most common aerobic microorganism was Streptococcus spр., recurrences developed in 21 % of cases.

Purpose of the study. To conduct typing of toxigenic strains of Clostridium difficile, obtained from oncological patients who are in hospital.Material and Methods. The study included 130 patients with Clostridium difficile – associated diarrhea. First, the presence of toxins A+B+ in the feces was determined by enzyme immunoassay on an automatic miniVidas analyzer from BioMieux SA (France). For screening using real-time PCR, 26 toxigenic Clostridium difficile were selected. For the study used the system GeneXpert company «Cepheid» (Sweden).Results. Of the 1287 patients with diarrhea who were treated in an oncologic hospital, 130 (10,1%) tested positive for toxin A+B+ Clostridium difficile. For the study using real-time PCR, 26 samples were taken. The average age of patients is 57 years. 10 (38,5%) toxigenic strains were identified as hypervirulent ribotype. 7/10 strains were isolated for 3 consecutive month. The average age of patients with hypervirulent strains was 45 years. Patients participating in the study, in most cases were from the surgical departments – 61,5%, from the therapeutic – 34,7%.Conclusion. The study showed that the prevalence of Clostridium difficile infection in our clinic is lower than in other countries. Although hypervirulent strains accounted for 1/3 of all typed Clostridium difficile, special attention should be paid to them. Delayed diagnosis, delay in the onset of specific therapy in cancer patients can lead to a deterioration in the quality of life and in some cases be fatal. PCR diagnostics can determine the hypervirulent ribotype and carry out epidemiological measures aimed at preventing local outbreaks in the hospital.

The purpose of the study: to identify the significance of anaerobic bacteria and analyze their role in the development of infectious complications in cancer patients. Material and Methods. The review includes data from clinical and in vitro studies published in Russian and international press for the period from 1989 to 2018. Results. Data analysis has shown that many aspects related to anaerobic non-sporeforming bacteria are insufficiently studied, although they can cause severe hospital infections. This is especially true for patients with immune system defects, including cancer patients. In this category of patients, anaerobic bacteria can cause infections of the maxillofacial region, intra-abdominal infections, lower respiratory tract infections, urinary infections, and blood flow infections. In cancer patients, infectious complications are more severe, and may adversely affect treatment outcomes. A long process of anaerobic cultivation dictates the need for empirical treatment of infection for an average of 6 to 7 days. Since the middle of the last century, metronidazole was the «gold standard» of therapy. However, today the situation has changed dramatically. More than 80 % of anaerobic strains are resistant to metronidazole. The problem of resistance of anaerobic bacteria to other antibacterial drugs has not been sufficiently studied. Conclusion. It is necessary to develop therapeutic approaches based on current data on the resistance mechanisms of non-sporeforming anaerobic bacteria.

The purpose of the study was to analyze infectious complications caused by multi-drug-resistant organisms depending on anticancer therapy.Material and Methods. A total of 229 cancer patients with infectious complications of cancer therapy were included into the study.Results. Lung cancer was the most predominant cancer (26.6 %) followed by gastric cancer (25.3 %) and esophageal cancer (14.4 %). Infectious complications occurring after surgery were observed in 83.4 % of the patients. Infectious complications caused by Acinetobacter baumannii were the most common (40.6 %), followed by Klebsiella pneumoniae (28.5 %), Pseudomonas aeruginosa (19.5 %), Staphylococcus spp. (9.4 %), and Enterococcus spp. (1.8 %).Conclusion. Infectious complications occurred more frequently in postoperative cancer patients (p

The purpose of the study was to evaluate the frequency of isolation of multi-resistant Acinetobacter baumannii in cancer patients and identify the mechanisms of resistance to carbapenems.Material and Methods. We analyzed 942 strains of A. baumannii isolated from clinical samples of cancer patients in the period 2014–16. The level of resistance to ampicillin-sulbactam, piperacillin-tazobactam, ceftazidime, cefepime, imipenem, meropenem, ciprofloxacin, amikacin, and to other antibiotics was determined. Carbapenem-resistant (Car-R) strains were examined for the presence of carbapenemases.Results. Between 2014 and 2016, the number of strains resistant to: ampicillin-sulbactam was 95.5–74.6 % (p≤0.0001), piperacillin – tazobactam 64.3–98.1 % (p

Aim of the study: To determine clinical course of Burkholderia cenocepacia bacteremia and outcomes in patients receiving cancer therapy. Materials and methods: We indentified 10 adult patients with culture-verified catheter-related Burkholderia cenocepacia bacteremia. Pathogens were identified with protein mass spectrometry of bacteria cells. Testing for the «Microscan WalkAway 40/96 Plus» (Germany) did antibiotic sensitivity or «VITEK 2» (France). Results: In the majority of cases course of bacteremia was indolent; this fact precluded its rapid identification with standard procedures for diagnosing bloodstream infection. All patients developed fever but we revealed neither leukocytosis nor leucopenia which could be attributed to active infection. However, antibiotic treatment was initiated during the 24 h after the first signs of infection in all cases. In one patient bacteremia was complicated with septic shock. We revealed that Burkholderia cenocepacia was able to form biofilms and persist in implanted venous port systems after treatment and in order to eradicate the pathogen venous catheters had to be removed despite effective antibacterial treatment. Initial treatment was prescribed empirically and further antibacterial treatment was adjusted based on sensitivity testing results in 7 patients. Burkholderia cenocepacia eradication rate was 100% and all patients were cured and were able to continue prescribed cancer therapy afterwards. Conclusion: given to the low frequency of Burkholderia cenocepacia sporadic infections, clinicians must be aware of the possibility of drugs and medical supplies contamination with this pathogen. If one reveals ≥1 case of Burkholderia cenocepacia-associated infection the internal investigation must be initiated. Empiric antimicrobial therapy widely prescribed to treat febrile neutropenia in cancer patients is effective in these cases. However, it cannot eradicate the pathogen from inner lumen of implanted venous catheters. Identification of the possible pathogen in blood cultures and antibiotics sensitivity testing using microbiological analyzers prompts the diagnosis of bacteremia and prescription of most effective therapy

The purpose of the study was to evaluate the frequency of isolation of multi-resistant Pseudomonas aeruginosa and identify the mechanisms of resistance to carbapenems.Material and methods. We analyzed 866 strains of Pseudomonos aeruginosaisolated from clinical samples from cancer patients in the period 2014–2016. the level of resistance to piperacillin/tazobactam, ceftazidime, cefepime, imipenem, meropenem, ciprofloxacin, amikacin in dynamics was determined. carbapenem-resistant (car-R) strains were examined for the presence of enzymes.Results. Between 2014 and 2016, the number of strains resistant to piperacillin/tazobactam was 20.1–12.9 %, to ceftazidime – 33.0–32.9 %, to cefepime – 25.6–32.9 %, ciprofloxacin – 36.8–43.8 %, amikacin – 23.8–24.9 %. No statistically significant differences were found (p>0.05). However, an increase in the number of car-R strains from 31.7 to 43.8 % was observed (p

The purpose of the study was to analyze the prevalence of multidrug-resistant (MDR) pathogens (Escherichia coli and Klebsiella pneumonia) isolated from cancer patients. material and methods. 862 strains of E. coli and 1 461 strains of K. pneumoniae isolated from wound, blood, urine and other pathological materials from cancer patients treated at N.N. Blokhin National Medical Research Center of Oncology (Moscow) between 2014 and 2016 were analyzed. results. Over the last 3 years, there has been a significant increase in the number of E.coli resistant to piperacillin-tazobactam (from 8.1 to 25 %), ceftriaxone (from 15.7 to 100 %), ertapenem (from 8.1 to 97.7 %), and amikacin (c 4.5 to 14.6 %). The number of E. coli producing carbapenemases has increased from 5.8 to 20.8 % (p≤0.0001). Among K. pneumoniae, a significant increase in the number of strains resistant to piperacillin-tazobactam (from 59.7 to 89.7 %), ceftazidime (from 62.8 to 82.8 %), ceftriaxone (from 62.8 to 100 %), cefepime (from 63.1 to 83.8 %), ertapenem (from 62.1 to 100 % ), imipenem (from 30.0 to 81.0 %), and meropenem (from 53.9 to 86.8% ) is observed. conclusion. Evaluation of the frequency of isolation of MDR microorganisms over time is an essential element of epidemiological surveillance and is necessary for the correct treatment of patients with infectious complications.

The purpose of the study was to determine the role of antibiotics as a risk factor of Clostridium difficile-associated diarrhea in hospitalized cancer patients.Material and Methods. The study included 844 hospitalized cancer patients with diarrhea. The presence of Clostridium difficile toxins A and B in the fecal samples was determined by enzyme immunoassay.Results. Clostridium difficile toxins A and B were detected in 100 cancer patients (42 % men and 58 % women). The incidence of Clostridium difficile-associated diarrhea was higher in women than in men (р

Skin and soft tissue infections are one of the most common nosocomial infections, which are caused most often by gram-positive bacteria (staphylococci, streptococci, enterococci) with multiple drug resistance. These infections are among the major nosocomial infections in oncology clinics along with respiratory and urinary tract infections, blood flow infections, febrile neutropenia, and fevers of unknown origin.The purpose of the study was to compare the clinical activity of two oxazolidinones: linezolid and tedizolide in patients with skin and soft tissue infections.Material and methods. We analyzed recent publications and data available in websites: rlsnet.ru, eucast.org, and medlux.ru.Results. Clinical trials showed that both oxazolidinones were comparable in clinical efficacy, microbiological activity, and incidence of side effects in skin and soft tissue infections caused by various resistant gram-positive microorganisms: methicillin-resistant staphylococcus aureus (MRSA) and vancomycin-resistant Streptococcus faecalis (VRE), as well as certain streptococci. The treatment regimen of tedizolide (200 mg once daily for 6 days) was compared with linezolid regimen (600 mg twice daily for 10 days). No comparisons were made with the 6-day linezolid regimen, although the authors concluded that shorter duration of treatment with tadizolide resulted in an equal effect. In addition, the minimum inhibitory concentrations (MICs) obtained by comparing the microbiological activity of these two agents showed the advantage of tedizolide against certain strains. However, the comparison was not made according to the EUCAST standards (Committee on Antimicrobial Susceptibility Testing). Concerning the cost of both drugs, treatment with linezolidom was 2-3 times cheaper than treatment with tidezolid, even with its shorter course.Conclusion. Thus, tedisolide was equally effective for linezolid. Data on the microbiological sensitivity of linezolid can be extrapolated to tedizolide in the absence of testing in laboratories. However, lower financial costs and wider range of microbiological activity make linezolid the drug of choice for the treatment of skin and soft tissue infections caused by resistant gram-positive microorganisms.

The differential diagnosis of pulmonary diseases is extremely difficult and requires high qualifications of the radiologist and clinician. The differential diagnosis is used to distinguish different lung diseases: nonspecific inflammatory lung diseases (empyema, abscess, pneumonia), tuberculosis, sarcoidosis, benign tumors, lung cancer, lymphogranulomatosis, metastatic changes, and inflammatory changes in lung tissue. We present a clinical case, in which the differential diagnosis between tumor and inflammatory changes in lung tissue allowed the choice of optimal treatment tactics.

The purpose of the study was to present data on polymixin-based antibiotics with activity against infections caused by multidrug- resistant Gram-negative bacteria, such as Acinetobacter baumannii, Klebsiella pneumoniae, and Pseudomonas aeruginosa.Material and methods. The review includes data from clinical as well as in vitro studies for the period 1998–2017. The search for relevant sources was carried out in the Medline, Cochrane Library, Elibrary and other databases.Results. The analysis of the data showed the presence of synergism and additive activity of polymyxin in combination with carbapenems, rifampicin and azithromycin. However, experimental data showed no direct positive correlation between combination of polymyxim and azithromycin/ rifampicin. In clinical studies, in hospital-acquired pneumonia, including ventilator-associated pneumonia, the clinical response rate of polymyxin B combined with other antibiotics ranged from 38 % to 88 %. High nephro-and neurotoxicity of polymyxin observed in previous studies can be explained by a lack of understanding of its toxicodynamics or the use of an incorrect dose.Conclusion. Polymyxin B in combination with other antibiotics is a promising treatment against infectious complications caused by multidrug resistant Gram-negative bacteria.

Introduction. Urinary tract infections are among the most frequently seen bacterial infections. Worldwide, about 150 million people are diagnosed with urinary tract infections each year, costing the global economy in excess of 3.5 billion US dollars. Urinary tract infections occur more frequently and exhibit more severe symptoms in cancer patients than in patients with other diseases. Material and methods. The paper analyzes the etiology of urinary tract infections in cancer patients during their stay in the hospital. Results. The presented data concern antibiotic-resistant ESKAPE pathogens (Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, and Enterobacter species). Comparative data on the sensitivity to different antibiotics were shown. Recommendations for treatment aimed at reducing the selective pressure of certain groups of antibiotics, in particular carbapenems, were given.

Nosocomial infections caused by gram-positive organisms, including Staphylococcus aureus and enterococci (Enterococcus faecium and Enterococcus faecalis) are steadily increasing in almost all clinics around the world. Cancer patients have a higher risk of hospital-acquired infections than non-cancer patients. Cancer patients are immunosuppressed due to increased use of broad-spectrum antibiotics and chemotherapy drugs, radiation therapy, surgery and use of steroids. This paper presents an analysis of resistance of gram-positive bacterial pathogens to antimicrobial agents to determine treatment strategy for cancer patients.

The problem of prevention and treatment of hospital-acquired (nosocomial) infections excites progressive minds of humanity for centuries. The risk and incidence of nosocomial infections are constantly increasing. It becomes harder and harder to fight with them. Special attention is paid to nosocomial infections caused by resistant gram-negative organisms. This is a problem for clinics in all countries. National programs for the prevention of the development and spread of resistant strains have been developed in the majority of countries. Infectious complications develop more frequently and more severe in cancer patients than in non-cancer patients. Infectious complications in these patients are mainly associated with hospital-acquired infections. Complications caused by resistant gram-negative microorganisms, such as P. aeruginosa, A. baumannii and K. rneumoniae are especially dangerous complications. The clinical management of these patients is difficult and requires teamwork of microbiologists and clinicians.

We have tested 253 strains (13 species) Candida spp. Determination of the minimum inhibitory concentration of amphotericin B was performed by 2 methods: epsilometric method (Etest®, BioMerieux, France) and on the instrument the Vitek2 (BioMerieux, France). In general, resistance was detected in 5 strains (2.1%) (C. parapsilosis – 4, C. tropicalis – 1). There were no resistance to amphotericin B among strains of C. albicans, C. glabrata and C.krusei. Coincidence evaluation results of the minimum inhibitory concentration of amphotericin B for categories sensitivity/resistance when tested strains 2 methods generally occurred in 98% of cases (248 of 253): 100% for the species C. albicans, C. glabrata and C.krusei, 92.2% for C. parapsilosis and 95% for C. tropicalis. The results of our study demonstrate a low degree of resistance of Candida spp. to amphotericin B, which allows the use of the drug in a

Evaluation of susceptibility of systemic antifungal agents against Candida spp. in recent years has been standardized and refined based on species-specific characteristics of Candida. In addition to new values clinical breakpoints were introduced epidemiological cutoff value. This value can serve as a sensitive marker of reduced susceptibility to the systemic antifungal agents. In our study was tested the resistance of fluconazole, voriconazole, posaconazole, anidulafungin, caspofungin, micafungin for 294 clinical strains of Candida spp. (2012–2014) from specimens of cancer patients. Definition of MIC was performed by epsilometric method (Е-test). The resistance to azoles in the average observed in 47.4%, to echinocandins – in 4.2%.