Evaluation of the BioFire® FilmArray® Pneumonia plus Panel for Detecting Bacterial Etiological Agents of Lower Respiratory Tract Infections in an Oncologic Hospital. Comparison with Conventional Culture Method.

Conventional methods used to determine pneumonia pathogens are characterized by low sensitivity and long turnaround times. Introducing new tests with better parameters in patients at higher risk of infections is highly anticipated. The results of the conventional quantitative culture method (CM) in determining the bacterial etiology of pneumonia were compared with the results of the Pneumonia plus Panel test (PNP; BioFire® Diagnostics, USA) in 79 samples of bronchoalveolar lavage (BAL). Materials were collected from 79 patients with suspected pneumonia treated in an oncologic hospital due to solid tumors. Only 16/79 BAL samples (20.3%) were true positive (TP) for bacterial etiology in CM vs. 27/79 samples (34.2%) true positive in the PNP test. The total agreement between methods of interpreting the result (positive or negative) was 84.8%. The most prevalent pathogens in both methods were Staphylococcus aureus, followed by Escherichia coli, Pseudomonas aeruginosa, and Haemophilus influenzae. The PNP test identified several respiratory pathogens that were not grown in culture. The semiquantitative value reported by the PNP test was higher than that reported by culture. The PNP test vs. combined test (PNP test and CM methods) demonstrated positive predictive value (PPV) and negative predictive value (NPV) values of 100.0% and 98.1%, and the sensitivity and specificity were 96.4% and 100.0%. The PNP test is a good tool for determining the etiology of bacterial pneumonia and may support the care of an oncologic patient. However, further large-sample studies are needed to research in strictly defined groups of oncologic patients.

The Impact of Nasal Staphylococcus aureus Carriage on Surgical-Site Infections after Immediate Breast Reconstruction: Risk Factors and Biofilm Formation Potential.

BACKGROUND Despite the benefits of implant-based breast reconstruction in patients with breast cancer, the procedure can be complicated by surgical site infections (SSI). This study aimed to evaluate the association between nasal carriage of Staphylococcus aureus strains and the incidence of SSI among patients who underwent reconstructive procedures. We also assessed the ability of colonizing S. aureus strains to form biofilm. MATERIAL AND METHODS Medical data from 124 patients with 132 post-mastectomy breast reconstructions performed at the Oncology Center in Bydgoszcz, Poland, between June 2020 and August 2021 were analyzed. A 90-day incidence of SSI was found in 7/132 reconstructions (5.3%). The study group included 132 reconstructions, and was divided into those with infection (n=7) and without infection (n=125). Between-group differences were assessed using the t test for continuous variables and chi-square test for categorical variables. Biofilm formation among 32 S. aureus strains was determined by using quantitative and qualitative assays. RESULTS There were no significant differences in relation to the patients' S. aureus colonization status. Infections occurred both in patients colonized and not colonized with S. aureus. S. aureus nasal carriage did not affect the rate of SSI at 90 days after surgery. About 97.0% of the strains had a strong capacity for biofilm formation. CONCLUSIONS There was no association between nasal carriage of strains of S. aureus and the incidence of SSI. However, further investigations on a larger group of patients and longer observation time are needed to investigate this potential risk factor in detail.

Did the COVID-19 Pandemic Truly Adversely Affect Disease Progress and Therapeutic Options in Breast Cancer Patients? A Single-Centre Analysis.

PURPOSE: The uncontrolled spread and transmission of SARS-CoV-2 infections has disrupted most areas of social and economic life all over the world. The most important changes concern problems related to the functioning of healthcare systems. The aim of this study was to evaluate clinical consequences associated with the COVID-19 pandemic for patients with newly diagnosed breast cancer, treated at our centre. METHODS: The study participants were patients first time diagnosed with breast cancer, treated between January 2019 and March 2021, who were provided any type of cancer treatment at our centre. The study determined the grade of clinical and pathological progress of the disease and types of cancer treatment applied in patients. RESULTS: In total, 2863 patients were included in the analysis. The number of hospitalized patients was 1228 (1123 treated surgically, 105 receiving conservative treatment) in 2019, 1318 (1206 and 112 patients, respectively) in 2020, and 317 (288 and 29 patients, respectively) in 2021. CONCLUSIONS: Despite many hazards associated with the new epidemiological situation, we were able to maintain the continuous operation of our centre. We have achieved a measurable success, and even managed to increase the number of treated breast cancer patients.

Clinical and Molecular Findings of Infections Caused by Extended-Spectrum ß-Lactamase-Producing Enterobacterales in Patients with Solid Tumors: A Single-Center Study.

Infectious complications caused by multidrug-resistant bacteria are a serious clinical and therapeutic problem. Our study aimed to analyze the genetic characteristics of extended-spectrum ß-lactamase-producing Enterobacterales (ESBL-E) that cause multidrug-resistant infections in patients with solid tumors. Identification of ESBL-encoding genes was performed by polymerase chain reaction (PCR) and sequencing. The clonal relationship of the isolates was evaluated by pulsed-field gel electrophoresis. Multilocus sequence typing (MLST) was carried out for selected Escherichia coli and Klebsiella pneumoniae isolates. All E. coli strains were classified into phylogenetic groups using the PCR-based approach. There were 735 patients with clinical symptoms of infections tested, of which 44 (6.0%) were positive for ESBL-E on genotypic testing. The most frequent organism was E. coli (n = 24, 54.5%), followed by K. pneumoniae (n = 13, 29.5%), Proteus mirabilis (n = 3, 6.8%), Enterobacter cloacae cplx (n = 2, 4.5%), and Klebsiella oxytoca (n = 2, 4.5%). Overall, 31 (70.5%) of the ESBL-E isolates carried only blaCTX-M-1-like genes, and the genes were found to be blaCTX-M-15 (n = 30, 68.2%) or blaCTX-M-3 (n = 1, 2.3%). Eleven strains (25%) had blaCTX-M-9-like genes, mostly blaCTX-M-27 (n = 10, 22.7%) and unique blaCTX-M-65 (n = 1, 2.3%). One isolate possessed both blaCTX-M-15 and blaCTX-M-27 genes, and another one produced TEM-12 ESBL. MLST analysis revealed E. coli sequence type (ST) 131 and ST361, and K. pneumoniae ST16, ST307, and ST437. Among E. coli isolates, the B2 phylogenetic group was predominant. Most of the strains showed resistance to third-generation cephalosporins and fluoroquinolones, and susceptibility to aminoglycosides and carbapenems. Patients with solid cancer and ESBL-E infections require special management since they are a population with a high threat of antibiotic-resistant infections. Carbapenems and aminoglycosides remain active antibiotics against these infections.

Clinical relevance of a degree of extracapsular extension in a sentinel lymph node in breast cancer patients: a single-centre study.

In some breast cancer (BC) patients, an examination of lymph nodes dissected during sentinel lymph node biopsy (SLNB) demonstrates a presence of metastatic lesions and extracapsular extension (ECE) in a SLN. This study aimed to evaluate clinical relevance of ECE in BC patients. This is a retrospective analysis of 891 patients with cancer metastases to SLN, referred to supplementary axillary lymph node dissection (ALND), hospitalized between Jan 2007 and Dec 2017. Clinical and epidemiological data was evaluated. Long-term treatment outcomes were analysed. In 433 (48.6%) patients, cancer metastases were limited to the SLN (group I), in 61 (6.8%) patients the SLN capsule was exceeded focally (≤ 1 mm-group II). In 397 (44.6%) patients, a more extensive ECE was found (> 1 mm-group III). Metastases to non-sentinel lymph nodes (nSLNs) were diagnosed in 27.0% patients from group I, 44.3% patients from group II and in 49.6% patients from group III. No statistically significant differences were observed in long-term treatment outcomes for compared groups. The presence of ECE is accompanied by a higher stage of metastatic lesions in the lymphatic system. The differences in this respect were statistically significant, when compared to the group of ECE(-) patients. ECE, regardless of its extent, did not impact the long-term treatment results. ECE remains an indication for supplementary ALND and for other equivalent cancer treatment procedures, regardless of ECE size.

Characteristics of ESBL-Producing Enterobacterales Colonizing the Gastrointestinal Tract in Patients Admitted to the Oncological Hospital.

We analyzed the prevalence and genetic characteristics of the extended-spectrum ß-lactamases (ESBLs)-producing Enterobacterales isolated from adult patients hospitalized in the oncological center in 2019. Out of 9372 patients admitted to the hospital, 1373 had been in various medical facilities during the last year, which was an indication to perform a screening test for ESBL-producing Enterobacterales colonizing their gastrointestinal tract. In eighty-three patients (6.1%), 85 ESBL producers were detected. These isolates included the following: Escherichia coli (n = 67; 78.8%), Klebsiella pneumoniae (n = 14; 16.5%), Enterobacter cloacae cplx (n = 3; 3.5%), and Klebsiella oxytoca (n = 1; 1.2%). CTX-M-1-like enzymes were the most common ESBLs (n = 67; 78.8%). Two K. pneumoniae isolates (2/85; 2.4%) additionally produced New Delhi-metallo-ß-lactamases (NDM). All isolates, except for K. oxytoca, were typed by pulsed-field gel electrophoresis (PFGE) and demonstrated high genetic diversity. The most prevalent phylogroups of E. coli were B2 group (n = 30; 44.8%), followed by A group (n = 25; 37.3%). These observations have motivated us to investigate the link between ESBL-E colonization and infection among patients with solid tumors.

Case Report: Echinocandin-Resistance Candida glabrata FKS Mutants From Patient Following Radical Cystoprostatectomy Due to Muscle-Invasive Bladder Cancer.

Invasive Candida glabrata infections are not common complications after radical cystoprostatectomy. Furthermore, resistance to echinocandins arising during the course of a patient's treatment is rarely recognised. We described a case of development of echinocandin resistance in a patient with muscle-invasive bladder cancer (pT2b N0 M0, high grade) diagnosis, subjected to radical cystoprostatectomy and exposed to echinocandins. A male patient with a previous surgical history after a traffic accident, who was operated on due to bladder cancer, underwent an episode of candidemia and mixed postoperative wound and urinary tract infection caused by C. glabrata and extended spectrum ß-lactamase (ESBL)-producing Escherichia coli during hospital treatment. The patient was started on caspofungin. Repeat blood cultures showed clearance of the bloodstream infection; however, infection persisted at the surgical site. Resistance to echinocandins developed within 2 months from the day of initiation of therapy with caspofungin in the C. glabrata strain obtained from the surgical site. The isolates sequentially obtained during the patient's treatment demonstrated resistance to echinocandins due to the mutation in hotspot 1 FKS2. Although resistance to echinocandins is relatively rare, it should be considered in oncological patients with increased complexity of treatment and intestinal surgery.

Incidence of genes encoding vanA/vanB vancomycin resistance in rectal swabs of patients with diagnosed cancer, on the day of admission to hospital, in a non-epidemic period.

INTRODUCTION: Rapid diagnosis is important for preventing infections due to vancomycin-resistant enterococci. AIM: To evaluate the status of gastrointestinal colonisation with strains containing vanA/vanB genes in oncological patients. MATERIAL AND METHODS: A total of 167 samples of rectal swabs taken from 161 patients (mean age: 63, range: 29-93 years) were examined, including 113 patients from surgical wards (70.2%) and 48 patients from non-surgical wards (29.8%), with diagnosed cancer. The tests were carried out within 24 h of admitting the patient to the department, using the Cepheid Xpert vanA/vanB test, with a CE marked GeneXpert® Instrument Systems analyser. Samples with positive vanB gene results were additionally seeded on chromogenic media. RESULTS: The presence of the vanA gene was found in 2.7% and 6.3% of the examined patients, respectively, from the surgical and non-surgical departments, which accounted for 3.7% of all the patients examined. The presence of the vanB gene was detected in 21.1% of the patients, but in no case was there any growth of vancomycin-resistant enterococci on the chromogenic medium. CONCLUSIONS: Patients admitted to non-surgical wards were more often colonised with vanA/vanB genes than were patients admitted to surgical wards, but the differences were not statistically significant.

Significance of Infections in Implant Loss After Breast Reconstruction in the Course of Breast Cancer Treatment.

The aim of the study was to analyze the reasons for removing implants after breast reconstruction in the course of treatment of breast cancer. The study involved 428 patients, who underwent a total of 648 breast reconstruction procedures using artificial implants. 47 out of 648 cases (7.3%) were identified in which the implant had to be removed. Of the 47 cases, 57.4% had undergone deferred reconstruction, and 42.6% immediate reconstruction; 27.7% had undergone pre-operative chemotherapy and radiotherapy, 27.7% pre-operative chemotherapy, and 2.1% pre-operative radiotherapy; 6.4% were diabetic, 4.3% active smokers, and more than 50.0% had BMI greater than 25 kg/m2. In 83.0% of the analyzed cases, the reason for removal of the implant was infection, in 8.5% it was local recurrence of breast cancer, in 4.3% it was damage (leakage) of the implant, and in 2.1% it was post-operative pain. About 87.0% of infections appeared within one year of implantation; however, less than a half developed within 90 days of the reconstructive surgery, and up to 30 days only about 13.0% had appeared. Among the etiological agents of infections were: coagulase-negative Staphylococcus (31.3%), Staphylococcus aureus (18.7%), Enterococcus faecalis (9.4%), Enterobacter cloacae (18.8%), Pseudomonas aeruginosa (12.5%), Acinetobacter lwoffii (3.1%), and other Gram-negative fermenting rods accounted for 6.2%. Infections were the most common reason for removing the implant after breast reconstruction. and occurred most often as late infections (>30 days after surgery). The time of observation for infectious complications should be at least 1 year.The aim of the study was to analyze the reasons for removing implants after breast reconstruction in the course of treatment of breast cancer. The study involved 428 patients, who underwent a total of 648 breast reconstruction procedures using artificial implants. 47 out of 648 cases (7.3%) were identified in which the implant had to be removed. Of the 47 cases, 57.4% had undergone deferred reconstruction, and 42.6% immediate reconstruction; 27.7% had undergone pre-operative chemotherapy and radiotherapy, 27.7% pre-operative chemotherapy, and 2.1% pre-operative radiotherapy; 6.4% were diabetic, 4.3% active smokers, and more than 50.0% had BMI greater than 25 kg/m2. In 83.0% of the analyzed cases, the reason for removal of the implant was infection, in 8.5% it was local recurrence of breast cancer, in 4.3% it was damage (leakage) of the implant, and in 2.1% it was post-operative pain. About 87.0% of infections appeared within one year of implantation; however, less than a half developed within 90 days of the reconstructive surgery, and up to 30 days only about 13.0% had appeared. Among the etiological agents of infections were: coagulase-negative Staphylococcus (31.3%), Staphylococcus aureus (18.7%), Enterococcus faecalis (9.4%), Enterobacter cloacae (18.8%), Pseudomonas aeruginosa (12.5%), Acinetobacter lwoffii (3.1%), and other Gram-negative fermenting rods accounted for 6.2%. Infections were the most common reason for removing the implant after breast reconstruction. and occurred most often as late infections (>30 days after surgery). The time of observation for infectious complications should be at least 1 year.

The analysis of human leukocyte antigen-G level in patients with endometrial cancer by Western blot technique.

PROBLEM: Aberrant expression of human leukocyte antigen-G (HLA-G) in various malignancies has been shown to participate in tumour development by suppressing immune regulation within the tumour microenvironment. The detection of HLA-G has reportedly been correlated with certain clinicopathological parameters in several neoplasms. Both the soluble and membranous forms of HLA-G are biologically active, and therefore, we aimed to evaluate the HLA-G level by Western blot technique. METHOD OF STUDY: The total amount of HLA-G protein was analyzed in the primary tumour in 113 tissue samples derived from patients with endometrial cancer. The HLA-G protein level was measured by Western Blot technique and was analyzed with respect to the clinicopathological parameters. RESULTS: Human leukocyte antigen-G protein levels were statistically significantly higher in the cancerous tissues derived from the women with advanced endometrial cancer than those from women with early stage disease. Moreover, we showed that endometrial cancer patients with lymph node metastases had statistically significantly higher HLA-G levels in the primary uterine tumour. CONCLUSION: The aberrant expression of HLA-G antigens by malignant cells could be one of the strategies tumour cells use to escape immune surveillance. The presence of HLA-G within the cancer nest and its microenvironment would seem to be linked to disease progression.

An analysis of the influence of infection on overall survival rates, following modified posterior pelvic exenteration for advanced ovarian cancer.

Objectives The aim of our study has been to determine the association between the appearance of infection after modified posterior pelvic exenteration (MPE) and TTC (time to adjuvant chemotherapy) and to examine whether the infection impacts clinical results by delaying the start of chemotherapy. Material and methods The present, retrospective study analyzed 77 patients who had undergone MPE followed by adjuvant chemotherapy. Either no residual tumor or tumor less than 2.5 mm was achieved in 76.7% of these patients. Patients were divided into two subgroups for comparison; the first group consisted of 41 patients with infections, the second group of 36 patients without infections. Infection after surgery was monitored within a 90-day postoperative period. Median TTC and OS (overall survival) was determined for those patients who developed infection as well as for those who did not. Results The expected 5-year survival rate was 0.40 (SD=0.09) for those patients without infection and 0.17 (SD=0.07) for those patients with infection. The survival curves of patients with infection and those without infection were statistically significantly different (p=0.038). Median TTC differed significantly for those patients who developed infection vs those patients who did not develop infection (37days vs 27.5 days, p=0.024), and patients without infection were statistically more likely to receive chemotherapy within 25 days following surgery than in the subsequent 25-42-day period compared to those patients who did develop infection (p=0.048). No statistically significant differences were found between the groups in relation to the initiation of chemotherapy within 42 days (p=0.445). Conclusions The absence of postoperative infection was associated with a better survival. Patients with infection were noted a longer time interval from surgery to start of chemotherapy without negative impact to OS.

Rapid Detection of Bloodstream Pathogens in Oncologic Patients with a FilmArray Multiplex PCR Assay: a Comparison with Culture Methods.

The results of the FilmArray® Blood Culture Identification Panel (BCID) (BioFire Diagnostics) and the culture with susceptibility testing of 70 positive blood cultures from oncologic patients were compared. The multiplex PCR assay (BCID) identified 81 of the 83 isolates (97.6%), covered by the panel. The panel produced results in significantly shorter time than standard identification methods, when counted from receiving positive blood cultures bottles to the final results. It is an accurate method for the rapid identification of pathogens and resistance genes from blood culture in oncologic patients.

Analysis of Treg cell population in patients with breast cancer with respect to progesterone receptor status.

Breast cancer is the most frequently diagnosed type of cancer in women worldwide. Both the development and progression of breast cancer are related to tumour evasion of the immune system through a process called cancer immune-editing, in which regulatory lymphocytes play an important role. The infiltration of Treg cells in patients with breast cancer has been proposed as an independent unfavourable prognostic factor. In the present study, we aimed to evaluate the percentages of the Treg cell populations in the peripheral blood of patients with breast cancer with respect to progesterone receptor expression. Peripheral blood samples were collected from 27 patients with breast cancer treated in the Clinical Department of Breast Cancer and Reconstructive Surgery of the Professor Franciszek Lukaszczyk Oncological Centre, Bydgoszcz. Flow cytometry was used to evaluate the percentage of CD25+/FOXP3+/CD127 (-/low) T cells within CD3+/CD4+ T cells. The presence of CD25+/FOXP3+/CD127 (-/low) T cells within CD3+/CD4+ T cells was identified in all the examined blood samples. A statistically significantly higher percentage of CD25+/FOXP3+/CD127 (-/low) T cells within CD3+/CD4+ T cells was observed in progesterone receptor (PR)-negative breast cancer patients when compared to PR-positive breast cancer patients. The observed high percentage of CD25+/FOXP3+/CD127 (-/low) T cells within CD3+/CD4+ T cells in PR (-) breast cancer patients when compared to PR (+) breast cancer patients seems to confirm the unfavourable prognostic significance of these cells in breast cancer patients. This may indicate a rationale for combining standard oncological treatment in breast cancer patients with Treg-depleting therapy.

[Bronchial bacterial colonization in patients with lung cancer]. / Bakteryjna kolonizacja drzewa oskrzelowego u chorych na raka pluca.

INTRODUCTION: Infections are a part of the natural course of lung cancer but few studies have looked at the clinical and microbiological documentation of infections in these patients. The aim of this study is to analyze the profile of potentially pathogenic bacteria that colonize the bronchial tree in patients with primary lung cancer. MATERIAL AND METHODS: The study was conducted from January 2006 to August 2007. It included 44 consecutive patients (34 males and 10 females) with primary lung cancer aged from 38 to 77 (mean age of 57.9 years). In all patients, bronchoalveolar lavage (BAL) was performed during bronchofiberoscopy. Obtained BAL fluid was subjected to microbiological examination. The number of bacteria present in 1 ml of fluid was estimated by quantitative culture. A diagnostic level was set on >or= 104 cfu/ml. RESULTS: In 26 (59.1%) of 44 patients physiologic bacterial flora was found in the bronchial tree. In three cases (6.8%), potentially pathological bacteria were cultured but their number was < 104 cfu/ml. In 15 (34.1%) cases, the colonization of potentially pathogenic bacteria was >or= 104 cfu/ml. Both Gram-positive and Gram-negative bacteria were isolated. The most frequently isolated bacterium in the first group was Streptococcus pneumoniae (n = 7), and in the second group Haemophilus influenzae (n = 3). Multibacterial colonization was found in five patients (11.4%). In four cases (9.1%), the bronchial tree was colonized simultaneously by two and in one case [2.3%] by three types of micro-organism. Multi-drug-resistant strains were not found in the examined materials but among Streptococcus pneumoniae the constitutive MLSB phenotype was observed. CONCLUSIONS: 1. Approximately 30% of patients with lung cancer had a respiratory tract colonized by micro-organisms whose number was higher than the assumed diagnostic level. 2. Among micro-organisms colonizing the lower respiratory tract, Gram-positive cocci such as Streptococcus pneumoniae and Staphylococcus aureus were dominant. 3. The analysis of antibiotic-resistance did not detect multi-drug-resistant micro-organisms but some strains of Streptococcus pneumoniae exhibited resistance to macrolide, lincosamide and streptogramin B.

[Bacteriological and mycological analysis of material taken from lower respiratory tract in patients with malignancy]. / Analiza bakteriologiczna i mikologiczna materialu pobranego z dolnych dróg oddechowych u chorych na nowotwór zlosliwy.

UNLABELLED: The immunosuppression and incorrect function of the natural protection mechanisms are conducive to lower respiratory tract infections. The patients with malignancy, especially with lung cancer, belong to the group at higher risk to develop an infection due to accumulation of numerous risk factors. OBJECTIVE: The aim of this study was to assess the occurrence of bacteria and fungi in materials taken from lower respiratory tract from the patients treated in Thoracic Surgery and Clinical Department of Thoracic Surgery and Tumours from 2000 to 2004. The frequency of occurrence of alert-pathogens was also analyzed. MATERIAL AND METHODS: The retrospective analysis was carried out among 102 positive samples (sputum--68, bronchial secretion--32 and bronchoalveolar lavage--2). The material was obtained from patients treated due to lung cancer (n=84), pulmonary metastases (n=6), primary neoplasms of the chest wall (n=2), lymphoma of the mediastinum (n=3), mesothelioma (n=1) and other malignancies (n=6). The examinations were conducted in compliance with the current procedures, generally accepted in microbiological laboratories. RESULTS: Seventy examined patients (68.63%) had bronchial colonization with bacteria being the potential etiologic agents of lower respiratory tract infections. The presence of yeast-like fungi was confirmed in 62 patients (60.78%). The most frequent strains isolated were: Enterobacteriaceae (40.86%), followed by Staphylococcus aureus (21.51%), Haemophilus influenzae (16.13%) and Streptococcus pneumoniae (7.53%). The nonfermenting gram-negative rods Pseudomonas spp. and Acinetobacter spp. occurred as follows: 6.45% and 3.23%. Among yeast-like fungi the most common species isolated was Candida albicans (63.77%) which occurred more frequently in sputum than in bronchial secretion (p < 0.0004). The strains of Enterobacteriaceae and nonfermenting gram-negative bacillus producing extended-spectrum beta lactamase (ESBL) were not discovered like MBL (metallo- beta lactamase) positive strains. All of the Staphylococcus aureus strains were sensitive to the methicillin. Haemophilus influenzae did not show ampicillin resistance. We observed two strains Streptococcus pneumoniae which were penicillin intermediate but susceptible to the third-generation cephalosporins. CONCLUSIONS: Identification of the potential etiological agents of lower respiratory tract infections can be useful in the rational management of the antibiotics policy in the patients with maliganacy.

[Ability of slime production Staphylococcus aureus strains obtained from clinical materials]. / Wytwarzanie sluzu przez szczepy Staphylococcus aureus pochodzace z materialów klinicznych.

UNLABELLED: Slime production defines the ability of bacterial strains to colonize host tissues and biomaterials. Slime production by coagulase-negative Staphylococcus and its role in disease have been studied intensively in recent years. Much less is known about this trait in species Staphylococcus aureus. The objective of the present study was: assessment of the frequency of slime production by examined isolates of S. aureus, estimation of the influence of strains' origin to occurrence of investigated trait, comparison sample method (broth medium) with solid medium method. MATERIAL AND METHODS: 62 strains of S. aureus were examined. They were obtained from clinical material taken from patients hospitalized in Regional Centre of Oncology, in Bydgoszcz. Slime production was determined by using Christensen's method and Congo red agar method. RESULTS: 50.0% isolates were able to produce slime. The findings obtained in both methods were comparable (p>0.05). Slime was more frequently produced by strains obtained from biomaterials than from purulent materials (p<0.02). CONCLUSIONS: On the basis of the obtained results it may be stated that slime production is a very common trait of S. aureus and depends on the origin of the strains.