The environmental occurrence of Pseudomonas aeruginosa Crone, Stephanie; Vives‐Flórez, Martha; Kvich, Lasse ...
APMIS : acta pathologica, microbiologica et immunologica Scandinavica,
March 2020, Volume:
128, Issue:
3
Journal Article
Peer reviewed
Pseudomonas aeruginosa is generally described as ubiquitous in natural settings, such as soil and water. However, because anecdotal observations and published reports have questioned whether or not ...this description is true, we undertook a rigorous study using three methods to investigate the occurrence of P. aeruginosa: We investigated environmental samples, analyzed 16S rRNA data, and undertook a systematic review and meta‐analysis of published data. The environmental sample screening identified P. aeruginosa as significantly associated with hydrocarbon and pesticide‐contaminated environments and feces, as compared to uncontaminated environments in which its prevalence was relatively low. The 16S rRNA data analysis showed that P. aeruginosa sequences were present in all habitats but were most abundant in samples from human and animals. Similarly, the meta‐analysis revealed that samples obtained from environments with intense human contact had a higher prevalence of P. aeruginosa compared to those with less human contact. Thus, we found a clear tendency of P. aeruginosa to be present in places closely linked with human activity. Although P. aeruginosa may be ubiquitous in nature, it is usually scarce in pristine environments. Thus, we suggest that P. aeruginosa should be described as a bacterium largely found in locations associated with human activity.
We have been monitoring the antifungal resistance in Candida parapsilosis isolates collected from inpatients at Madrid metropolitan area hospitals for the last 3 years. The study aimed to elucidate ...the presence of fluconazole-resistant C. parapsilosis genotypes in Madrid. From January 2019 to December 2021, a total of 354 C. parapsilosis isolates (
= 346 patients) from blood (76.6%) or intraabdominal samples were collected and genotyped using species-specific microsatellite markers. Antifungal susceptibilities to amphotericin B, the triazoles, micafungin, anidulafungin, and ibrexafungerp were performed according to EUCAST E.Def 7.3.2; the
gene was sequenced in fluconazole-resistant isolates. A total of 13.6% (
= 48/354) isolates (one per patient) were found to be resistant to fluconazole and non-wild-type to voriconazole but fully susceptible to ibrexafungerp. Resistant isolates were mostly sourced from blood (
= 45/48, 93.8%) and were detected in five hospitals. Two hospitals accounted for a high proportion of resistant isolates (
= 41/48). Resistant isolates harbored either the Y132F ERG11p amino acid substitution (
= 43) or the G458S substitution (
= 5). Isolates harboring the Y132F substitution clustered into a clonal complex involving three genotypes (one genotype accounted for
= 39/43 isolates) that were found in four hospitals. Isolates harboring the G458S substitution clustered into another genotype found in a fifth hospital. C. parapsilosis genotypes demonstrating resistance to fluconazole have been spreading across hospitals in Madrid, Spain. Over the last 3 years, the frequency of isolation of such isolates and the number of hospitals affected is on the rise.
We previously conducted a multicenter surveillance study on
epidemiology and antifungal resistance in Madrid (CANDIMAD study; 2019-2021), detecting an increase in fluconazole-resistant
. We here ...present data on isolates collected in 2022. Furthermore, we report the epidemiology and antifungal resistance trends during the entire period, including an analysis per ward of admission.
spp. incident isolates from blood cultures and intra-abdominal samples from patients cared for at 16 hospitals in Madrid, Spain, were tested with the EUCAST E.Def 7.3.2 method against amphotericin B, azoles, micafungin, anidulafungin, and ibrexafungerp and were molecularly characterized. In 2022, we collected 766
sp. isolates (686 patients; blood cultures, 48.8%).
was the most common species found, and
was undetected. No resistance to amphotericin B was found. Overall, resistance to echinocandins was low (0.7%), whereas fluconazole resistance was 12.0%, being higher in blood cultures (16.0%) mainly due to fluconazole-resistant
clones harboring the Y132F-R398I ERG11p substitutions. Ibrexafungerp showed
activity against the isolates tested. Whereas
was the dominant species in most hospital wards, we observed increasing
proportions in blood. During the entire period, echinocandin resistance rates remained steadily low, while fluconazole resistance increased in blood from 6.8% (2019) to 16% (2022), mainly due to fluconazole-resistant
(2.6% in 2019 to 36.6% in 2022). Up to 7 out of 16 hospitals were affected by fluconazole-resistant
. In conclusion, rampant clonal spreading of
fluconazole-resistant genotypes is taking place in Madrid.
Abstract
Objectives
We prospectively monitored the epidemiology and antifungal susceptibility of Candida spp. from blood cultures and intra-abdominal samples in patients admitted to hospitals in the ...Madrid area.
Methods
Between 2019 and 2021, we prospectively collected incident isolates one per species, patient and compartment (blood cultures versus intra-abdominal samples) from patients admitted to any of 16 hospitals located in Madrid. We studied the antifungal susceptibilities to amphotericin B, triazoles, micafungin, anidulafungin and ibrexafungerp following the EUCAST E.Def 7.3.2 procedure.
Results
A total of 2107 Candida spp. isolates (1895 patients) from blood cultures (51.7%) and intra-abdominal samples were collected. Candida albicans, the Candida glabrata complex, the Candida parapsilosis complex, Candida tropicalis and Candida krusei accounted for 96.9% of the isolates; in contrast, Candida auris was undetected. Fluconazole resistance in Candida spp. was higher in blood cultures than in intra-abdominal samples (9.1% versus 8.2%; P > 0.05), especially for the C. parapsilosis complex (16.6% versus 3.6%, P < 0.05), whereas echinocandin resistance tended to be lower in blood cultures (0.5% versus 1.0%; P > 0.05). Resistance rates have risen, particularly for fluconazole in blood culture isolates, which increased sharply in 2021. Ibrexafungerp showed in vitro activity against most isolates. Species distributions and resistance rates varied among hospitals.
Conclusions
Whereas no C. auris isolates were detected, fluconazole-resistant C. parapsilosis isolates have been spreading across the region and this has pulled up the rate of fluconazole resistance. In contrast, the rate of echinocandin resistance continues to be low.
•National Forest Inventory (NFI) data were analysed.•Biomass equations were used for tree species and components, including roots.•Most C stocks were estimated using regional-specific equations and ...C-content data.•Assumption of a C-content of 50% led to overestimation of C stocks.•Increasing both forest and C-density (Mg C ha−1) increases live tree C stocks.
Almost 50% of the land in Galicia (NW Spain) is covered by forest (minimum area of land of 1 ha with tree crown cover of more than 10%) and the region is the top timber–producing area in Spain. Regional changes in forest live tree biomass and carbon stocks were estimated from National Forest Inventory (NFI) data covering almost 40 years, i.e. between NFI-1 (1972) and NFI–4 (2009). Carbon stocks were estimated from biomass of different tree species and components, including roots. Biomass equations were applied to the tree stock data for different species and diameter classes. The biomass increased in all species or groups for the period considered. However, although the biomass of softwood species (mainly Pinus spp.) increased, because of the increase in the number of trees belonging to the largest diameter classes (DC), the balance of the number of small trees (DC < 25 cm) was negative. The estimated total tree dry biomass (above- and below-ground) in the region increased from 94.77 Tg (teragrams) to 217.09 Tg between the first (1972) and fourth NFI (2009). This is the equivalent of an increase in carbon stocks from 45.51 Tg to 102.83 Tg. Most of the carbon stocks were estimated by applying regional-specific biomass equations and C-content data for different tree species and components. Assuming a global carbon content of 50% led to overestimation of the total carbon stocks by between 4.1% and 5.6%. Although harvesting intensity in the region is one of the highest in Europe, the live tree C stocks have increased; this was attributed to the increase in forestland area as well as to the increased C density, i.e. from 40 Mg (megagrams) C ha−1 in NFI-1 to 72 Mg C ha−1 in NFI-4.
Candidaemia and invasive candidiasis are typically hospital-acquired. Genotyping isolates from patients admitted to different hospitals may be helpful in tracking clones spreading across hospitals, ...especially those showing antifungal resistance.
We characterized
clusters by studying
isolates (
,
= 1041;
,
= 354, and
,
= 125) from blood cultures (53.8%) and intra-abdominal samples (46.2%) collected as part of the CANDIMAD (
in Madrid) study in Madrid (2019-2021). Species-specific microsatellite markers were used to define the genotypes of
spp. found in a single patient (singleton) or several patients (cluster) from a single hospital (intra-hospital cluster) or different hospitals (widespread cluster).
We found 83 clusters, of which 20 were intra-hospital, 49 were widespread, and 14 were intra-hospital and widespread. Some intra-hospital clusters were first detected before the onset of the COVID-19 pandemic, but the number of clusters increased during the pandemic, especially for
. The proportion of widespread clusters was significantly higher for genotypes found in both compartments than those exclusively found in either the blood cultures or intra-abdominal samples. Most
and
-resistant genotypes were singleton and presented exclusively in either blood cultures or intra-abdominal samples. Fluconazole-resistant
isolates belonged to intra-hospital clusters harboring either the Y132F or G458S ERG11p substitutions; the dominant genotype was also widespread.
the number of clusters-and patients involved-increased during the COVID-19 pandemic mainly due to the emergence of fluconazole-resistant
genotypes.
AQP4 (aquaporin-4)-immunoglobulin G (IgG)-mediated neuromyelitis optica spectrum disorder (NMOSD) is an inflammatory demyelinating disease that affects the central nervous system, particularly the ...spinal cord and optic nerve; remyelination capacity in neuromyelitis optica is yet to be determined, as is the role of AQP4-IgG in cell differentiation.
We included three groups-a group of patients with AQP4-IgG-positive neuromyelitis optica, a healthy group, and a sham group. We analyzed differentiation capacity in cultures of neurospheres from the subventricular zone of mice by adding serum at two different times: early and advanced stages of differentiation. We also analyzed differentiation into different cell lines.
The effect of sera from patients with NMOSD on precursor cells differs according to the degree of differentiation, and probably affects oligodendrocyte progenitor cells from NG2 cells to a lesser extent than cells from the subventricular zone; however, the resulting oligodendrocytes may be compromised in terms of maturation and possibly limited in their ability to generate myelin. Furthermore, these cells decrease in number with age. It is very unlikely that the use of drugs favoring the migration and differentiation of oligodendrocyte progenitor cells in multiple sclerosis would be effective in the context of neuromyelitis optica, but cell therapy with oligodendrocyte progenitor cells seems to be a potential alternative.
Several recent works have raised the possibility of the contribution of the lymphocyte activation gene 3 (LAG3) protein in the inflammatory processes of multiple sclerosis (MS). Results of studies on ...the possible association between
gene variants and the risk of MS have been inconclusive. In this study, we tried to show the possible association between the most common single nucleotide variants (SNVs) in the
and
genes (these two genes are closely related) and the risk of MS in the Caucasian Spanish population. We studied the genotypes and allelic variants
,
, and
in 300 patients diagnosed with MS and 400 healthy patients using specific
-based qPCR assays. We analyzed the possible influence of the genotype frequency on age at the onset of MS, the severity of MS, clinical evolutive subtypes of MS, and the
genotype. The frequencies of the
,
, and
genotypes and allelic variants were not associated with the risk of MS and were unrelated to gender, age at onset and severity of MS, the clinical subtype of MS, and
genotype. The results of the current study showed a lack of association between the
,
, and
SNVs and the risk of developing MS in the Caucasian Spanish population.
According to several studies, inflammatory factors could be related to the pathogenesis of idiopathic restless legs syndrome (RLS). In addition, RLS and Parkinson's disease (PD) have shown a possible ...relationship, and recent studies have shown an association between
rs1922452 and
rs951818 single nucleotide variants (SNVs) and the risk for PD. For these reasons, we investigated the possible association between common variants in the
genes (which encoded proteins involved in inflammatory and autoimmune responses) and the risk for RLS in a Caucasian Spanish population. We assessed the frequencies of
rs1922452,
rs951818, and
rs870849 genotypes and allelic variants in 285 patients with idiopathic RLS and 350 healthy controls using a specific
-based qPCR assay. We also analyzed the possible influence of the genotypes' frequencies on several variables, including age at onset of RLS, gender, family history of RLS, and response to drugs commonly used in the treatment of RLS. We found a lack of association between the frequencies of genotypes and allelic variants of the 3 SNVs studied and the risk of RLS, and a weak though significant association between the
rs1922452 GG genotype and an older age at onset of RLS. With the exception of this association, our findings suggest that common SNVs in the
genes are not associated with the risk of developing idiopathic RLS in Caucasian Spanish people.
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