The Impact of Pseudomonas aeruginosa Infection in Adult Cystic Fibrosis Patients-A Single Polish Centre Study.

BACKGROUND: Pseudomonas aeruginosa (PA) is one of the most predominant pathogens of lung infections, often causing exacerbations in adult patients with cystic fibrosis (CF). MATERIALS AND METHODS: Microbiological characterization of 74 PA isolates and to evaluate the correlations between the bacterial features and 44 adult Polish CF cohort clinical parameters. RESULTS: The most common variant in the CF transmembrane conductance regulator (CFTR) gene was F508del (76.3%), followed by 3849+10kbC>T (26.3%). A total of 39.4% of the PA isolates showed multiple resistances. In patients with parameters pointing to a decline in lung function, there was a statistically significant moderate correlation with ß-lactam resistance and a weak correlation between hospital frequency and colistin resistance. The mucoidity did not correlate with the biofilm formation ability, which showed 41.9% of the isolates. Proteolytic activity, observed in 60.8% of the clinical isolates, was weakly associated with motility detected in 78.4% of the strains. The genetic profiles of the PA were highly heterogeneous, and a weak positive correlation was established between cluster group and biofilm formation. CONCLUSION: The findings suggest that there is a high variety in P. aeruginosa populations in adult CF patients. There is a need to monitor PA strains in groups of patients with cystic fibrosis, in particular, in terms of the occurrence of antibiotic resistance related to a decline in lung function.

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.

Microbiological Quality of Milk Donated to the Regional Human Milk Bank in Warsaw in the First Four Years of Activity.

As the survival rate for preterm infants increases, more emphasis is placed on improving health-related quality of life through optimal nutritional management. Human Milk Banks (HMBs) provide bioactive nutrients and probiotic microorganisms to premature newborns, especially in the first year of life. Donated milk screening and selection of potential donors ensures the quality and microbiological safety of the donated milk. Therefore we reviewed the basic characteristics of donors and the amounts and contamination of breast milk donated to the Regional Human Milk Bank (RHMB) in Warsaw. In four years, the RHMB collected 1445.59 L of milk, of which 96.60% was distributed among hospitalised infants. Additionally, breastmilk from donor candidates (139 samples from 96 women) was tested at least once in the first year of lactation. First analyses showed that 18 women's milk samples were microbiologically pure, and 78 samples had one or more species of commensal and/or potentially pathogenic bacteria. In human milk samples from 10 women, the bacteria level was above the standard required by the RHMB; therefore, donors were re-educated, and further samples were tested. Most women followed the recommendations on hygienic expression and storage of milk before transfer to the RHMB. Our analysis will help to increase the accessibility and quality of raw donor milk and to meet the needs of more newborns.

Effect of Low Amperage Electric Current on Staphylococcus Aureus-Strategy for Combating Bacterial Biofilms Formation on Dental Implants in Cystic Fibrosis Patients, In Vitro Study.

Cystic fibrosis is an inherited disease that affects multiple organs and systems. The oral cavity can serve as a substantial source of bacteria, causing respiratory infections and diseases which continue to dictate the clinical course of the disease and prognosis in patients with CF. Low voltage and electric current could effectively kill bacteria and biofilms, and the activity of milliampere currents could be used as an effective method of fighting bacteria. This study evaluated the effect of low amperage electric current on the formation of Staphylococcus aureus biofilms on dental implants such as titanium and zirconium in patients with cystic fibrosis. Our studies suggest that a constant electric current at a low intensity of 1 mA and 10 mA is inhibiting bacterial adhesion, detaching biofilm-forming bacteria on biomaterials used in dental implants such as titanium and zirconium, and destroying bacterial cells of Staphylococcus aureus strains. In addition, we observed the selection of an appropriate biomaterial for implants in people affected by chronic diseases, such as CF, should be carefully planned.

Biofilm Formation on Dental Implant Biomaterials by Staphylococcus aureus Strains Isolated from Patients with Cystic Fibrosis.

Implants made of ceramic and metallic elements, which are used in dentistry, may either promote or hinder the colonization and adhesion of bacteria to the surface of the biomaterial to varying degrees. The increased interest in the use of dental implants, especially in patients with chronic systemic diseases such as cystic fibrosis (CF), is caused by an increase in disease complications. In this study, we evaluated the differences in the in vitro biofilm formation on the surface of biomaterials commonly used in dentistry (Ti-6Al-4V, cobalt-chromium alloy (CoCr), and zirconia) by Staphylococcus aureus isolated from patients with CF. We demonstrated that S. aureus adherence and growth depends on the type of material used and its surface topography. Weaker bacterial biofilm formation was observed on zirconia surfaces compared to titanium and cobalt-chromium alloy surfaces. Moreover, scanning electron microscopy showed clear differences in bacterial aggregation, depending on the type of biomaterial used. Over the past several decades, S. aureus strains have developed several mechanisms of resistance, especially in patients on chronic antibiotic treatment such as CF. Therefore, the selection of an appropriate implant biomaterial with limited microorganism adhesion characteristics can affect the occurrence and progression of oral cavity infections, particularly in patients with chronic systemic diseases.

Combination of High-Pressure Processing and Freeze-Drying as the Most Effective Techniques in Maintaining Biological Values and Microbiological Safety of Donor Milk.

BACKGROUND: Human milk banks have a pivotal role in provide optimal food for those infants who are not fully breastfeed, by allowing human milk from donors to be collected, processed and appropriately distributed. Donor human milk (DHM) is usually preserved by Holder pasteurization, considered to be the gold standard to ensure the microbiology safety and nutritional value of milk. However, as stated by the European Milk Banking Association (EMBA) there is a need to implement the improvement of the operating procedure of human milk banks including preserving and storing techniques. AIM: The purpose of this study was to assess the effectiveness and safety of the selected new combination of methods for preserving donor human milk in comparison with thermal treatment (Holder pasteurization). METHODS: We assessed (1) the concentration of bioactive components (insulin, adiponectin, leptin, activity of pancreatic lipase, and hepatocyte growth factor) and (2) microbiological safety in raw and pasteurized, high-pressure processed and lyophilization human breast milk. RESULTS: The combination of two techniques, high-pressure processing and freeze-drying, showed the best potential for preserving the nutritional value of human milk and were evaluated for microbiological safety. Microbiological safety assessment excluded the possibility of using freeze-drying alone for human milk sample preservation. However, it can be used as a method for long-term storage of milk samples, which have previously been preserved via other processes. CONCLUSION: The results show that high-pressure treatment is the best method for preservation that ensures microbiological safety and biological activity but subsequent freeze-drying allowed long-term storage without loss of properties.

Human Milk Oligosaccharides Exhibit Biofilm Eradication Activity Against Matured Biofilms Formed by Different Pathogen Species.

Human milk oligosaccharides (HMOs) have been shown to exhibit plenty of benefits for infants, such as prebiotic activity shaping the gut microbiota and immunomodulatory and anti-inflammatory activity. For some pathogenic bacteria, antimicrobial activity has been proved, but most studies focus on group B streptococci. In the present study, we investigated the antimicrobial and antibiofilm activities of the total and fractionated HMOs from pooled human milk against four common human pathogenic Gram-negative species (Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, and Burkholderia cenocepacia) and three Gram-positive species (Staphylococcus aureus, Enterococcus faecium, and Enterococcus faecalis). The activity of HMOs against enterococci and B. cenocepacia are addressed here for the first time. We showed that HMOs exhibit a predominant activity against the Gram-positive species, with E. faecalis being the most sensitive to the HMOs, both in planktonic bacteria and in biofilms. In further tests, we could exclude fucosyllactose as the antibacterial component. The biological significance of these findings may lie in the prevention of skin infections of the mother's breast as a consequence of breastfeeding-induced skin laceration and/or protection of the infants' nasopharynx and lung from respiratory pathogens such as staphylococci.

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.

Tannic acid-modified silver nanoparticles enhance the anti-Acanthamoeba activity of three multipurpose contact lens solutions without increasing their cytotoxicity.

BACKGROUND: Free-living amoebae of the genus Acanthamoeba are cosmopolitan, widely distributed protozoans that cause a severe, vision-threatening corneal infection known as Acanthamoeba keratitis (AK). The majority of the increasing number of AK cases are associated with contact lens use. Appropriate eye hygiene and effective contact lens disinfection are crucial in the prevention of AK because of the lack of effective therapies against it. Currently available multipurpose contact lens disinfection systems are not fully effective against Acanthamoeba trophozoites and cysts. There is an urgent need to increase the disinfecting activity of these systems to prevent AK infections. Synthesized nanoparticles (NPs) have been recently studied and proposed as a new generation of anti-microbial agents. It is also known that some plant metabolites, including tannins, have anti-parasitic activity. The aim of this study was to evaluate the anti-amoebic activity and cytotoxicity of tannic acid-modified silver NPs (AgTANPs) conjugated with selected multipurpose contact lens solutions. METHODS: The anti-amoebic activities of pure contact lens care solutions, and NPs conjugated with contact lens care solutions, were examined in vitro by a colorimetric assay based on the oxido-reduction of alamarBlue. The cytotoxicity assays were performed using a fibroblast HS-5 (ATCC CRL-11882) cell line. The results were statistically analysed by ANOVA and Student-Newman-Keuls test using P < 0.05 as the level of statistical significance. RESULTS: We show that the NPs enhance the anti-Acanthamoeba activities of the tested contact lens solutions without increasing their cytotoxicity profiles. The activities are enhanced within the minimal disinfection time recommended by the manufacturers. CONCLUSIONS: The conjugation of the selected contact lens solutions with AgTANPs might be a novel and promising approach for the prevention of AK infections among contact lens users.

Fungal infection of cystic fibrosis patients - single center experience.

INTRODUCTION: Cystic fibrosis (CF) is the most common monogenetic autosomal recessive disease in the human population. This systemic disease is characterized by changes in multiple organs, mainly in the lung tissue and digestive tract. More than 59% of CF patients become sensitized to fungal spores, mostly Aspergillus fumigatus. 5-15% of CF patients develop allergic bronchopulmonary aspergillosis. The aim of the study was to analyse the occurrence of yeast and filamentous fungi of the respiratory infections in CF patients and evaluation of drug resistance. MATERIAL AND METHODS: Between 2006 and 2014, mycological evaluation of 42 patients hospitalized at the National Institute of Tuberculosis and Lung Diseases was carried out. RESULTS: 217 specimens from pulmonary tract were collected from 42 patients with cystic fibrosis. 205 (68%) strains of yeast and 96 (32%) filamentous fungi strains were cultured. The most common mould strain was A. fumigatus - 22,2% (67 species). All isolates of filamentous fungi were in vitro 100% susceptible to itraconazole, voriconazole, posaconazole and amphotericin B. CONCLUSIONS: A. fumigatus and C. albicans were the most common etiological agents of fungal respiratory pathogens associated with CF patients. A. fumigatus strains were in vitro 100% susceptible to azole and amphotericin B. Two strains of C. albicans and one strain of C. tropicalis were non-susceptible to azole (fluconazole, itraconazole and voriconazole). Scedosporium apiospermum was resistant to amphotericin B (MIC > 32 mg/l) and susceptible to voriconazole (MIC 0.094 mg/l).

[Frequency of detection of soluble antigens of Candida spp. and Aspergillus spp. using serological assays in body fluids of patients of Central Clinical Hospital in Warsaw].

INTRODUCTION: Immunodeficient patients, e.g. transplant recipients, patients treated with corticosteroids, people with AIDS and individuals undergoing prolonged antibiotic therapy are at high risk of invasive fungal infections, especially invasive aspergillosis. Basic method for detection of organ/systemic fungal infection is serological monitoring in body fluids, first of all in serum, bu also in broncho-alveolar lavages (BALF). Proven invasive fungal infection should be diagnosed by culture of the pathogen or histopathological examination of infected tissues, however the detection of soluble fungal antigens in body fluids gives enough information for diagnosis of probable fungal infection, according to European Organization for Research and Treatment of Cancer recommendations, what allows introduction of antifungal therapy. Aim of the study was to asses the frequency of detection of circulation soluble fungal antigens with use of immunoenzymatic techniques in patients hospitalized between 2010 and 2015 in Independent Public Central Clinical Hospital (IPCCH) in Warsaw. Methods: In IPCCH, between 2010 and 2015, 6475 serum samples, taken from 2096 patients, was tested for Candida spp. mannan antigen, and 7745 sera from 2243 patients were tested for Candida spp. mannan antigen, and 7745 sera from 2243 patients were tested for galactomannan antigen of Aspergillus spp, as well as 64 samples of BALF. Material was collected mainly from haematopoietic stem cell transplant recipients, hospitalized in Haematology and Oncology Clinics, during their routine pos-transplant monitoring. Testing was performed with use of quantitative (Candida antigen) or semiquantitative (Aspergillus antigen) immunoenzymatic methods (BioRad-Platelia), according to respective protocols. Results: During examined period, increase in number of examinations was observed, starting from 1311 tests performed in 2010, up to 3052 examination in 2015. In 2015 testing for Aspergillus antigen in BALF samples was also introduced, resulting in 64 samples tested. Candida spp. antigen was detected in 171 samples (2,7% of all tested samples), and Aspergillus galactomannan was detected in 645 serum samples (8,4%) and 8 BALF samples (12,5%). Majority of examinations was performed for patients hospitalized in Haematology and Oncology Clinics (72,7%), Blood Vessel Surgery and Transplantology Clinics (3,8%), as well as in patients under care of post-transplantation (8,3%) and haematology (4,2%) out-patients clinics. Conclusions: (i) In the 2015-2015 visible increase in number of fungal antigens examinations was observed, (ii) significant number of examinations was performed in onco-haematological patients (88,7%), what also indicates main risk group, (iii) 8,3% of fungal antigen testing was performed in solid organ transplant recipients, the second risk group for invasive fungal infection.

[Mycological analysis of clinical materials of patients receiving total parenteral nutrition]. / Mikologiczna analiza próbek materialu klinicznego uzyskanego od chorych zywionych pozajelitowo.

The most frequent etiological factors of fungal infections in patients receiving total parenteral nutrition (TPN) belong to Candida genus of the yeastlike fungi. In the TPN patients the several infectious complications can develop: venous catheter infection, catheter candidemia (fungemia), fungal endocarditis or fungal ophtalmitis. The capability of hydrolytic (proteolytic, lipolytic) enzymes secretion as well as biofilm formation on artificial surfaces are the most important factors of fungal strains pathogenity. In the study from clinical materials of 37 patients receiving total parenteral nutrition 31 strains of Candida glabrata (56.4%), 13 strains of Candida albicans (23.6%), 3 Candida tropicalis strains, 2 Candida krusei strains, 2 Candida lusitaniae strains and 1 strain of Candida inconspicua were identified. The phenotypic analysis of isolated strains were performed using API YM (bioMerieux) tests for the enzymatic activity determination. Simultaneously the proteolytic and lipolytic activity analysis were performed. Candida albicans isolates secreted 10 out of 19 enzymes and Candida glabrata 7. The secretion of proteases was demonstrated in 12 C. albicans strains. All Candida glabrata isolates from examined and from control group secreted proteolitic enzymes. Candida glabrata is the dominant species in clinical materials of patients receiving total parenteral nutrition. The numerous isolation of C. glabrata from clinical materials of patients receiving total parenteral nutrition might be connected with the selection of azole resistant strains and also to ability of creatin biofilm on the biomaterial surfaces.