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result(s) for
"Klim, Aleksandra"
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Microbial co-occurrences on catheters from long-term catheterized patients
by
Bergeron, Karla
,
Dodson, Karen W.
,
Flores-Mireles, Ana L.
in
631/326/1320
,
631/326/2565/107
,
692/4025
2024
Catheter-associated urinary tract infections (CAUTIs), a common cause of healthcare-associated infections, are caused by a diverse array of pathogens that are increasingly becoming antibiotic resistant. We analyze the microbial occurrences in catheter and urine samples from 55 human long-term catheterized patients collected over one year. Although most of these patients were prescribed antibiotics over several collection periods, their catheter samples remain colonized by one or more bacterial species. Examination of a total of 366 catheter and urine samples identify 13 positive and 13 negative genus co-occurrences over 12 collection periods, representing associations that occur more or less frequently than expected by chance. We find that for many patients, the microbial species composition between collection periods is similar. In a subset of patients, we find that the most frequently sampled bacteria,
Escherichia coli
and
Enterococcus faecalis
, co-localize on catheter samples. Further, co-culture of paired isolates recovered from the same patients reveals that
E. coli
significantly augments
E. faecalis
growth in an artificial urine medium, where
E. faecalis
monoculture grows poorly. These findings suggest novel strategies to collapse polymicrobial CAUTI in long-term catheterized patients by targeting mechanisms that promote positive co-associations.
The authors examine temporal polymicrobial community composition in patients with long-term urinary catheters to identify species co-occurrences and demonstrate uropathogenic
Escherichia coli
augments growth of a prevalent opportunistic uropathogen in urine.
Journal Article
Longitudinal multi-omics analyses link gut microbiome dysbiosis with recurrent urinary tract infections in women
2022
Recurrent urinary tract infections (rUTIs) are a major health burden worldwide, with history of infection being a significant risk factor. While the gut is a known reservoir for uropathogenic bacteria, the role of the microbiota in rUTI remains unclear. We conducted a year-long study of women with (
n
= 15) and without (
n
= 16) history of rUTI, from whom we collected urine, blood and monthly faecal samples for metagenomic and transcriptomic interrogation. During the study 24 UTIs were reported, with additional samples collected during and after infection. The gut microbiome of individuals with a history of rUTI was significantly depleted in microbial richness and butyrate-producing bacteria compared with controls, reminiscent of other inflammatory conditions. However,
Escherichia coli
gut and bladder populations were comparable between cohorts in both relative abundance and phylogroup. Transcriptional analysis of peripheral blood mononuclear cells revealed expression profiles indicative of differential systemic immunity between cohorts. Altogether, these results suggest that rUTI susceptibility is in part mediated through the gut–bladder axis, comprising gut dysbiosis and differential immune response to bacterial bladder colonization, manifesting in symptoms.
Multi-omics analyses of faecal, urine and blood samples from women with and without recurrent urinary tract infections reveal that gut dysbiosis and differential immune responses may play a role in risk of infection via the gut–bladder axis.
Journal Article
Fibrinolytic-deficiencies predispose hosts to septicemia from a catheter-associated UTI
2024
Catheter-associated urinary tract infections (CAUTIs) are amongst the most common nosocomial infections worldwide and are difficult to treat partly due to development of multidrug-resistance from CAUTI-related pathogens. Importantly, CAUTI often leads to secondary bloodstream infections and death. A major challenge is to predict when patients will develop CAUTIs and which populations are at-risk for bloodstream infections. Catheter-induced inflammation promotes fibrinogen (Fg) and fibrin accumulation in the bladder which are exploited as a biofilm formation platform by CAUTI pathogens. Using our established mouse model of CAUTI, here we identified that host populations exhibiting either genetic or acquired fibrinolytic-deficiencies, inducing fibrin deposition in the catheterized bladder, are predisposed to severe CAUTI and septicemia by diverse uropathogens in mono- and poly-microbial infections. Furthermore, here we found that
Enterococcus faecalis
, a prevalent CAUTI pathogen, uses the secreted protease, SprE, to induce fibrin accumulation and create a niche ideal for growth, biofilm formation, and persistence during CAUTI.
Catheter-associated urinary tract infections can often lead to secondary bloodstream infections, and catheter-induced bladder inflammation. In this work, authors utilise murine models to probe defective fibrinolysis drives extravascular fibrin formation, potentially predisposing hosts to severe CAUTI.
Journal Article
Optimization of DNA extraction from human urinary samples for mycobiome community profiling
by
Anger, Jennifer Tash
,
Underhill, David M.
,
Ackerman, James E.
in
Analysis
,
Bacteria
,
Bacterial genetics
2019
Recent data suggest the urinary tract hosts a microbial community of varying composition, even in the absence of infection. Culture-independent methodologies, such as next-generation sequencing of conserved ribosomal DNA sequences, provide an expansive look at these communities, identifying both common commensals and fastidious organisms. A fundamental challenge has been the isolation of DNA representative of the entire resident microbial community, including fungi.
We evaluated multiple modifications of commonly-used DNA extraction procedures using standardized male and female urine samples, comparing resulting overall, fungal and bacterial DNA yields by quantitative PCR. After identifying protocol modifications that increased DNA yields (lyticase/lysozyme digestion, bead beating, boil/freeze cycles, proteinase K treatment, and carrier DNA use), all modifications were combined for systematic confirmation of optimal protocol conditions. This optimized protocol was tested against commercially available methodologies to compare overall and microbial DNA yields, community representation and diversity by next-generation sequencing (NGS).
Overall and fungal-specific DNA yields from standardized urine samples demonstrated that microbial abundances differed significantly among the eight methods used. Methodologies that included multiple disruption steps, including enzymatic, mechanical, and thermal disruption and proteinase digestion, particularly in combination with small volume processing and pooling steps, provided more comprehensive representation of the range of bacterial and fungal species. Concentration of larger volume urine specimens at low speed centrifugation proved highly effective, increasing resulting DNA levels and providing greater microbial representation and diversity.
Alterations in the methodology of urine storage, preparation, and DNA processing improve microbial community profiling using culture-independent sequencing methods. Our optimized protocol for DNA extraction from urine samples provided improved fungal community representation. Use of this technique resulted in equivalent representation of the bacterial populations as well, making this a useful technique for the concurrent evaluation of bacterial and fungal populations by NGS.
Journal Article
Food-induced anaphylaxis in children less than 2 years of age
by
Cichocka-Jarosz, Ewa
,
Klim, Liliana
,
Jedynak-Wąsowicz, Urszula
in
Allergies
,
Anaphylaxis
,
Pediatrics
2025
Anaphylaxis is an acute, life-threatening condition representing a systemic hypersensitivity reaction, particularly triggered by food in young children. Its rising prevalence in the paediatric population has made it a critical topic in clinical practice, with epinephrine as the recommended treatment.
This study aimed to characterize severe allergic reactions in children aged 0-2 years, focusing on gender, age, allergens, symptoms, and treatments applied.
A retrospective study was conducted using the hospital database to review anaphylaxis cases in children under 2 years of age hospitalized in a paediatric allergy department.
Between 2014 and 2023, 87 patients (54 boys; mean age: 12.3 months, median age: 10 months, range: 4-24 months) with anaphylaxis were admitted to our department, comprising approximately 1% of all annual paediatric hospitalizations. The average onset time for symptoms was 17 min. Cow's milk and hen's egg were the most frequent triggers. Mucocutaneous symptoms (urticaria, angioedema; 81 patients; 93.1%) often appeared with respiratory symptoms. Asthma and hen's egg protein allergy were identified as risk factors for more severe reactions. Grade 4 anaphylaxis was observed in 38 cases (approximately 43% of all cases), though only 8 patients (10.5% of patients who received medication administered by professional staff) received epinephrine. Glucocorticosteroids were the most common treatment administered by medical staff.
Anaphylaxis is a multifaceted, life-threatening condition in infants, with significant diagnostic challenges. Our findings confirm insufficient use of epinephrine in managing severe allergic reactions in this age group.
Journal Article