Urine Bacteriology in Post-Kidney Transplant Patients with Double-J Stents

Background: Kidney transplantation is the gold standard treatment modality for patients with end-stage renal disease. Ureteric stenting is commonly used during kidney transplantation to reduce the incidence of ureteric complications post-transplantation. The presence of ureteric stents could be complicated by bacterial colonisation and urinary tract infections. Objective: To identify the urinary flora in patients with double-J stents following kidney transplantation and establish bacteria colonisation and their antimicrobial susceptibility. Methods: Over one-year, single urine samples of consecutive 100 post-renal transplant patients were subjected to bacteriologic analysis. Early morning midstream urine was obtained into a sterile bottle from all the participants for laboratory analysis. Results: The mean age of post kidney transplantation patients was 47.6 ±12.3 years. Hypertension and diabetes were the commonest co-morbidities associated with End-Stage-Renal-Disease (ESRD), accounting for 61% and 28%, respectively. E. coli was the commonest isolate (70.4%). Microbiological evidence of Urinary Tract Infection (UTI) revealed by pyuria (pus cells >4/HPF) was found in 40.9%. Tigecycline, nitrofurantoin and tetracycline showed the highest sensitivity pattern in 9%, 8% and 8%, respectively, with significant resistance against cephalosporins and fluoroquinolones. Conclusion: The fourth week of double-J ureteric stent insertion in kidney transplant recipients showed a high incidence of urinary bacterial colonisation.

Influence of Selected Restorative Materials on the Environmental pH: In Vitro Comparative Study

In dental caries treatment, it is worth using such restorative materials that may limit plaque accumulation. The pH of the filling seems to be an important factor affecting the potential bacterial colonisation. Our study aimed to assess how selected restorative materials influence the environmental pH. A total of 150 specimens (30 of each: Ketac Molar, Riva LC, Riva SC, Filtek Bulk Fill, and Evetric) were placed in 100 sterile hermetic polyethene containers with saline and stored in 37 °C. The pH of each sample was measured using the electrode Halo HI13302 (Hanna Instruments, Poland) at specific points in time for 15 days. The initial pH levels were significantly lower for glass ionomer cements (3.9–4.7) compared to composites (5.9–6.0). With time, the pH increased for samples with glass ionomer cements (by nearly 1.5), whereas it decreased for samples with composites (maximally by 0.8). In the end, all materials were in the pH range between 5.3 and 6.0. The highest final pH was obtained with Ketac Molar at about 5.9. Double samples had lower pH values than single samples, irrespective of the type of material. In conclusion, immediately after application, restorative materials decreased the environmental pH, especially light-cured glass ionomer cements. For glass ionomers, within two weeks, the pH increased to levels comparable with composites.

Tyrosine Kinase Self-Phosphorylation Controls Exopolysaccharide Biosynthesis in Gluconacetobacter diazotrophicus Strain Pal5

The biosynthesis of exopolysaccharides (EPSs) is essential for endophytic bacterial colonisation in plants bacause this exopolymer both protects bacterial cells against the defence and oxidative systems of plants and acts on the plant colonisation mechanism in Gluconacetobacter diazotrophicus. The pathway involved in the biosynthesis of bacterial EPS has not been fully elucidated, and several areas related to its molecular regulation mechanisms are still lacking. G. diazotrophicus relies heavily on EPS for survival indirectly by protecting plants from pathogen attack as well as for endophytic maintenance and adhesion in plant tissues. Here, we report that EPS from G. diazotrophicus strain Pal5 is a signal polymer that controls its own biosynthesis. EPS production depends on a bacterial tyrosine (BY) kinase (Wzc) that consists of a component that is able to phosphorylate a glycosyltranferase or to self-phosphorylate. EPS interacts with the extracellular domain of Wzc, which regulates kinase activity. In G. diazotrophicus strains that are deficient in EPS production, the Wzc is rendered inoperative by self-phosphorylation. The presence of EPS promotes the phosphorylation of a glycosyltransferase in the pathway, thus producing EPS. Wzc-mediated self-regulation is an attribute for the control of exopolysaccharide biosynthesis in G. diazotrophicus.

Evaluation of Streptococcus oralis adhesion and biofilm formation on laser-processed titanium

To prevent implant-associated infections, surface modifications need to be developed that prevent bacterial colonisation and biofilm formation. In the present study, titanium surfaces were processed by nanosecond-pulsed laser ablation to generate a variety of different structures (anatase, rutile, Osteon, as well as Osteon additionally coated with silver and clove nanoparticles). Analysis of adhesion and biofilm formation of the oral pioneer bacterium Streptococcus oralis could demonstrate antibacterial properties of anatase surfaces. For clinical translation, the effect should be enhanced by further adaption and combined with the osseointegrative Osteon structure

Airway Bacteria Quantification Using Polymerase Chain Reaction Combined with Neutrophil and Eosinophil Counts Identifies Distinct COPD Endotypes

Background: Chronic obstructive pulmonary disease (COPD) inflammatory endotypes are associated with different airway microbiomes. We used quantitative polymerase chain reaction (qPCR) analysis of sputum samples to establish the bacterial load upper limit in healthy controls; these values determined the bacterial colonisation prevalence in a longitudinal COPD cohort. Bacteriology combined with sputum inflammatory cells counts were used to investigate COPD endotypes. Methods: Sixty COPD patients and 15 healthy non-smoking controls were recruited. Sputum was analysed by qPCR (for Haemophilus influenzae, Moraxella catarrhalis, Streptococcus pneumoniae and Psuedomonas aeruginosa) and sputum differential cell counts at baseline and 6 months. Results: At baseline and 6 months, 23.1% and 25.6% of COPD patients were colonised with H. influenzae, while colonisation with other bacterial species was less common, e.g., S. pneumoniae—1.9% and 5.1%, respectively. H. influenzae + ve patients had higher neutrophil counts at baseline (90.1% vs. 67.3%, p < 0.01), with similar results at 6 months. COPD patients with sputum eosinophil counts ≥3% at ≥1 visit rarely showed bacterial colonisation. Conclusions: The prevalence of H. influenzae colonisation was approximately 25%, with low colonisation for other bacterial species. H. influenzae colonisation was associated with sputum neutrophilia, while eosinophilic inflammation and H. influenzae colonisation rarely coexisted.

Bacterial colonisation during regular daily use of a power-driven water flosser and risk for cross-contamination. Can it be prevented?

Objective To assess whether bacterial colonisation in a power-driven water flosser can be prevented. Materials and methods Twenty-four patients undergoing supportive periodontal treatment used 2 power-driven water flossers [Sonicare AirFloss (SAF), AirFloss Ultra (SAFU)] for 12 weeks each as follows: (a) with bottled water (BW); (b) with BW and cleaning the device extra-orally twice per week with chlorhexidine gluconate or (c) essential-oil-based (EO) mouth-rinse; (d) with EO only. Water-jet samples were taken after 6 and 12 weeks with the used nozzle and after exchanging to a brand-new nozzle. After 12 weeks, all devices underwent an intensive cleaning procedure. Samples were analysed by PCR-based method for cariogenic and periodontal pathogens and culture for staphylococci, aerobe gram-negative bacteria, and Candida sp. Results Contamination of SAF/SAFU with Streptococcus mutans was found in > 95% of the samples; periodontal pathogens and aerobe gram-negative bacteria were detected in 19–56% of the samples, while Staphylococcus aureus and Candida sp. were identified only in few samples. Contamination rate was basically unaffected by time-point, device, or way of use. Further, exchanging the nozzle did not prevent transmission of a contaminated water-jet, but the intensive cleaning reduced most of the pathogens significantly, except of S. mutans. Conclusion Neither a specific way of use nor exchanging the nozzle prevented bacterial colonisation and transmission of biofilm components via the water-jet of SAF/SAFU. Clinical relevance Bacterial colonisation in a power-driven water flosser seems impossible to prevent; to restrict the risk of cross-contamination within a household, one device per person should be recommended.

Infections in CSF Shunts and External Ventricular Drainage

Infection in those with hydrocephalus shunts or external drains (EVDs) can cause serious central nervous system damage with lasting sequelae. The infections usually involve bacterial colonisation and biofilm formation in the catheters. The nature and sources of pathogens and preventive measures are discussed. The risks of infection in shunts and EVDs is different. Infection in shunts is almost always initiated at their insertion or revision (exceptions are described). In contrast, in EVDs, the risk of infection persists throughout their use. The pathogen profile is also different. These factors are important considerations when planning preventive measures. Newer strategies such as antimicrobial catheters are discussed. Diagnosis of EVD infections in an already ill patient is difficult but guidelines can be useful. Treatment of the shunt and EVD infections are also addressed, with reference to modes and routes of antibiotic administration.