Die Rolle der 11β-hydroxysteroid dehydrogenase 1 bei der Regulation der Hypothalamus-Hypophysen-Nebennierenrinden-Achse in rheumatoider Arthritis

Background Patients with rheumatoid arthritis exhibit abnormal hypothalamic- pituitary-adrenal (HPA) axis activity. The basis for this abnormality is not known. Rheumatoid arthritis is associated with increased extra-adrenal synthesis of active glucocorticoids by the 11β-hydroxysteroid dehydrogenase type 1 (11β-HSD1) enzyme. 11β-HSD1 is expressed in the central nervous system, including regions involved in HPA axis regulation. This study examined whether altered 11β-HSD1 expression within these regions contributes to HPA axis dysregulation during arthritis. Methods The expression of 11β-HSD1, and other components of glucocorticoid signalling, were examined in various brain regions and the pituitary gland of mice with experimentally-induced arthritis. Two arthritis protocols were employed: The K/BxN spontaneous arthritis model for chronic arthritis and the K/BxN serum transfer arthritis model for acute arthritis. Results 11β-HSD1 was expressed in the hippocampus, hypothalamus, cortex, cerebellum and pituitary gland. Hypothalamic 11β-HSD1 expression did not change in response to arthritis in either model. Pituitary 11β-HSD1 expression was however significantly increased in both chronic and acute arthritis models. Hippocampal 11β-HSD1 was decreased in acute but not chronic arthritis. Chronic, but not acute, arthritis was associated with a reduction in hypothalamic corticotropin-releasing hormone and arginine vasopressin expression. In both models, serum adrenocorticotropic hormone and corticosterone levels were no different from non-inflammatory controls. Conclusion These findings demonstrate inflammation-dependent regulation of 11β-HSD1 expression in the pituitary gland and hippocampus. The upregulation of 11β-HSD1 expression in the pituitary during both chronic and acute arthritis, and thus an increase in glucocorticoid negative feedback, could contribute to the abnormalities in HPA axis activity seen in immune-mediated arthritis.Einleitung Patienten mit rheumatoider Arthritis (RA) weisen Auffälligkeiten in der Aktivität ihrer Hypothalamus-Hypophysen-Nebennierenrinden-Achse (HHN- Achse) auf. Der Grund für diese Auffälligkeiten ist bisher unbekannt. RA ist assoziiert mit einer Zunahme der extraadrenalen Glucocorticoid-Synthese durch das Enzym 11β-Hydroxysteroid-Dehydrogenase 1 (11β-HSD1). 11β-HSD1 wird im zentralen Nervensystem exprimiert, unter anderem in Regionen die an der Regulation der HHN-Achse beteiligt sind. In dieser Studie wurde untersucht, inwieweit eine veränderte Expression von 11β-HSD1 in diesen Regionen zu der beschriebenen HHN-Achsen-Dysregulation in Patienten mit RA beiträgt. Methodik Die Expression von 11β-HSD1 und anderen Komponenten der Glucocorticoid- Signalübertragung wurde in verschiedenen Hirnarealen sowie der Hypophyse untersucht in Mäusen mit experimentell induzierter Arthritis. Hierfür wurden zwei Protokolle verwendet: Das K/BxN-Spontan-Arthritis-Modell als eine chronische Form der Arthritis und das K/BxN-Serumübertragungs-Arthritis- Modell, als eine akute Form der Arthritis. Ergebnisse Die Expression von 11β- HSD1 wurde nachgewiesen in Hippocampus, Hypothalamus, Cortex, Cerebellum und Hypophyse. In beiden Mausmodellen kam es zu keiner Veränderung der 11β- HSD1-Expression im Hypothalamus in den arthritischen Mäusen. Im Gegensatz dazu war die 11β-HSD1-Expression in der Hypophyse signifikant erhöht in den arthritischen Mäusen beider Modelle. Die 11β-HSD1-Expression im Hippocampus war erniedrigt in den akuten, jedoch nicht in den chronischen Arthritis- Mausmodellen. Chronische, jedoch nicht akute Arthritis, war assoziiert einer reduzierten Expression von Corticotropin-releasing Hormone und Arginin- Vasopressin im Hypothalamus. In beiden Mausmodellen unterschieden sich die Serumspiegel von Adrenocorticotropin und Corticosteron nicht zwischen den arthritischen Mäusen und ihren Kontrollen. Schlussfolgerungen Diese Ergebnisse zeigen eine entzündungsabhängige Regulation der 11β-HSD1-Expression in der Hypophyse und dem Hippocampus. Die Hochregulierung der 11β-HSD1-Expression in der Hypophyse in chronischer und akuter Arthritis, und ein dementsprechend verstärktes negatives Feedback durch Glucocorticoide, könnten zu den HHN- Achsen-Auffälligkeiten beitragen, die in rheumatoider Arthritis beobachtet werden

Evaluation of CARBA PAcE, a novel rapid test for detection of carbapenemase-producing Enterobacterales

Introduction. Carbapenemase-producing Enterobacterales (CPE) are an increasing threat to global health. Fast detection is crucial for patient management and outbreak control. Hypothesis/Gap statement. Recently, a new commercial colorimetric test, CARBA PAcE, was released that has not yet been scientifically evaluated. Aim. Our goals were to evaluate the performance of CARBA PAcE using a large variety of different CPE. Methodology. CARBA PAcE was challenged with 107 molecularly characterized CPE and 53 non- CPE controls. Isolates were grown on MuellerHinton agar (MHA); in the case of a falsenegative result, isolates were additionally inoculated on Columbia blood agar (CBA) and CARBA PAcE was repeated. The test was performed according to the manufacturer's protocol. Results. CARBA PAcE showed an overall sensitivity and specificity of 72 % [confidence interval (CI) 62-80 %] and 91 % (CI 79-97 %), respectively, when isolates were grown on MHA. With growth on CBA, detection improved (especially of metallo-fllactamases), resulting in an extrapolated sensitivity of 89 % (CI 81-94 %) for all carbapenemases and 96 % (CI 89-99 %) for the four major carbapenemases (NDM, OXA-48- like, KPC, VIM). Conclusion. CARBA PAcE is a simple and very rapid test for the detection of CPE which performs well for the major carbapenemases when isolates are grown on CBA. Laboratories should be aware of the limitations of this assay, such as moderate sensitivity when isolates are grown on more challenging agars such as MHA and the poor detection of some rare carbapenemases (e.g. IMI, OXA-58)

Systematic Comparison of Three Commercially Available Combination Disc Tests and the Zinc-Supplemented Carbapenem Inactivation Method (zCIM) for Carbapenemase Detection in Enterobacterales Isolates

Detection of carbapenemases in Enterobacterales is crucial for patient treatment and infection control. Among others, combination disc tests (CDTs) with different inhibitors (e.g., EDTA) and variations of the carbapenem inactivation method (CIM) are recommended by EUCAST or the CLSI and are used by many laboratories as they are relatively inexpensive. In this study, we compare three commercially available CDTs, faropenem disc testing (FAR), and the zinc-supplemented CIM (zCIM) test for the detection of carbapenemase-producing Enterobacterales (CPE). The Rosco KPC/MBL and OXA-48 Confirm kit (ROS-CDT), the Liofilchem KPC&MBL&OXA-48 disc kit (LIO-CDT), Mastdiscs Combi Carba plus (MAST-CDT), FAR, and zCIM were challenged with 106 molecularly characterized CPE and 47 non-CPE isolates. The sensitivities/specificities were 86% (confidence interval [CI], 78 to 92%)/98% (CI, 89 to 100%) for MAST-CDT and ROS-CDT, 96% (CI, 91 to 99%)/87% (CI, 74 to 95%) for LIO-CDT, and 99% (CI, 95 to 100%)/81% (CI, 67 to 91%) for FAR compared to 98% (CI, 93 to 100%)/100% (CI, 92 to 100%) for zCIM. The CDTs showed great performance differences depending on the carbapenemase class, with MAST-CDT and LIO-CDT best detecting class B, ROS-CDT best detecting class A, and LIO-CDT best detecting class D carbapenemases. The overall performance of commercially available CDTs was good but varied greatly for different carbapenemases and between manufacturers, compared with FAR and zCIM, which performed well for all carbapenemase types. For reliable carbapenemase detection, CDTs should preferably not be used as the sole test but can be part of a diagnostic strategy when combined with other assays (e.g., CIM-based, immunochromatographic, or molecular tests)

In vitro activity of mecillinam, temocillin and nitroxoline against MDR Enterobacterales

Background With increasing resistance to common antibiotics the treatment of urinary tract infections has become challenging and alternative therapeutic options are needed. In the present study, we evaluate the activity of three older and less frequently used antibiotics against MDR Enterobacterales. Methods Susceptibility of mecillinam, temocillin and nitroxoline was assessed in Enterobacterales isolated from urinary specimens with elevated MICs of third-generation cephalosporins. Susceptibility was determined by the recommended reference MIC methods and additionally by disc diffusion. All isolates were characterized for common beta-lactamases by phenotypic and molecular assays. Results In total 394 Enterobacterales were included. The most common resistance mechanisms were ESBLs (n = 273), AmpC (n = 132), carbapenemases [n = 12, including OXA-48-like (n = 8), VIM (n = 2), KPC (n = 1) and NDM (n = 1)] or others (n = 2). Resistance was observed in 59% of isolates to ceftazidime, in 41% to piperacillin/tazobactam and in 54% to ciprofloxacin. In comparison, resistance was less frequent against mecillinam (15%), temocillin (13%) or nitroxoline (2%). Mecillinam showed higher activity in Enterobacter spp., Escherichia coli and in OXA-48-like-producing isolates compared with temocillin, which was more active in Proteus mirabilis and in ESBL-producing isolates. Activity of nitroxoline was high against all isolates, including carbapenemase-producing isolates. Correlation between disc diffusion and MIC methods was good for mecillinam and moderate for temocillin and nitroxoline. Conclusions Mecillinam, temocillin and nitroxoline show good to excellent in vitro activity in MDR Enterobacterales. The activity of mecillinam and temocillin was higher in certain species and restricted depending on beta-lactamase production while nitroxoline showed universally high activity irrespective of species or beta-lactamase present

Comparison of Two Commercially Available qPCR Kits for the Detection of Candida auris

Contains fulltext : 231352.pdf (publisher's version ) (Open Access

Emergence of Tn1999.7, a New Transposon in bla(OXA-48)-Harboring Plasmids Associated with Increased Plasmid Stability 1999.7

OXA-48 is the most common carbapenemase in Enterobacterales in Germany and many other European countries. Depending on the genomic location of bla(OXA-48), OXA-48-producing isolates vary in phenotype and intra- and interspecies transferability of bla(OXA-48). In most bacterial isolates, bla(OXA-48) is located on one of seven variants of Tn1999 (Tn1999.1 to Tn1999.6 and invTn1999.2). Here, a novel Tn1999 variant, Tn1999.7, is described, which was identified in 11 clinical isolates from 2016 to 2020. Tn1999.7 differs from Tn1999.1 by the insertion of the 8,349-bp Tn3 family transposon Tn7442 between the lysR gene and bla(OXA-48) open reading frame. Tn7442 carries genes coding for a restriction endonuclease and a DNA methyltransferase as cargo, forming a type III restriction modification system. Tn1999.7 was carried on an similar to 71-kb IncL plasmid in 9/11 isolates. In one isolate, Tn1999.7 was situated on an similar to 76-kb plasmid, harboring an additional insertion sequence in the plasmid backbone. In one isolate, the plasmid size is only similar to 63 kb due to a deletion adjacent to Tn7442 that extends into the plasmid backbone. Mean conjugation rates of the Tn1999.7-harboring plasmids in J53 ranged from 4.47 x 10(-5) to 2.03 x 10(-2), similar to conjugation rates of other pOXA-48-type IncL plasmids. The stability of plasmids with Tn1999.7 was significantly higher than that of a Tn1999.2-harboring plasmid in vitro. This increase in stability could be related to the insertion of a restriction-modification system, which can promote postsegregational killing. The increased plasmid stability associated with Tn1999.7 could contribute to the further spread of OXA-48

Surface water in Lower Saxony: A reservoir for multidrug-resistant Enterobacterales

The emergence of extended-spectrum β-lactamase and carbapenemase-producing Enterobacterales (ESBL-E and CPE, respectively) is a threat to modern medicine, as infections become increasingly difficult to treat. These bacteria have been detected in aquatic environments, which raises concerns about the potential spread of antibiotic resistance through water. Therefore, we investigated the occurrence of ESBL-E and CPE in surface water in Lower Saxony, Germany, using phenotypic and genotypic methods. Water samples were collected from two rivers, five water canals near farms, and 18 swimming lakes. ESBL-E and CPE were isolated from these samples using filters and selective agars. All isolates were analyzed by whole genome sequencing. Multidrug-resistant Enterobacterales were detected in 4/25 (16%) water bodies, including 1/2 rivers, 2/5 water canals and 1/18 lakes. Among all samples, isolates belonging to five different species/species complexes were detected: Escherichia coli (n = 10), Enterobacter cloacae complex (n = 4), Citrobacter freundii (n = 3), Citrobacter braakii (n = 2), and Klebsiella pneumoniae (n = 2). Of the 21 isolates, 13 (62%) were resistant at least to 3rd generation cephalosporins and eight (38%) additionally to carbapenems. CPE isolates harbored blaKPC-2 (n = 5), blaKPC-2 and blaVIM-1 (n = 2), or blaOXA-181 (n = 1); additionally, mcr-9 was detected in one isolate. Two out of eight CPE isolates were resistant to cefiderocol and two to colistin. Resistance to 3rd generation cephalosporins was mediated by ESBL (n = 10) or AmpC (n = 3). The presence of AmpC-producing Enterobacterales, ESBL-E and CPE in northern German surface water samples is alarming and highlights the importance of aquatic environments as a potential source of MDR bacteria

OXA-484, an OXA-48-Type Carbapenem-Hydrolyzing Class D beta-Lactamase From Escherichia coli

OXA-48-like carbapenemases are among the most frequent carbapenemases in Gram-negative Enterobacterales worldwide with the highest prevalence in the Middle East, North Africa and Europe. Here, we investigated the so far uncharacterized carbapenemase OXA-484 from a clinical E. coli isolate belonging to the high-risk clone ST410 regarding antibiotic resistance pattern, horizontal gene transfer (HGT) and genetic support. OXA-484 differs by the amino acid substitution 214G compared to the most closely related variants OXA-181 (214R) and OXA-232 (214S). The bla(OXA)(-)(484) was carried on a self-transmissible 51.5 kb IncX3 plasmid (pOXA-484) showing high sequence similarity with plasmids harboring bla(OXA)(-)(181). Intraspecies and intergenus HGT of pOXA-484 to different recipients occurred at low frequencies of 1.4 x 10(-7) to 2.1 x 10(-6). OXA-484 increased MICs of temocillin and carbapenems similar to OXA-232 and OXA-244, but lower compared with OXA-48 and OXA-181. Hence, OXA-484 combines properties of OXA-181-like plasmid support and transferability as well as beta-lactamase activity of OXA-232

OXA-48-like carbapenemases in Proteus mirabilis – novel genetic environments and a challenge for detection

ABSTRACTOXA-48-like enzymes represent the most frequently detected carbapenemases in Enterobacterales in Western Europe, North Africa and the Middle East. In contrast to other species, the presence of OXA-48-like in Proteus mirabilis leads to an unusually susceptible phenotype with low MICs for carbapenems and piperacillin-tazobactam, which is easily missed in the diagnostic laboratory. So far, there is little data available on the genetic environments of the corresponding genes, blaOXA-48-like, in P. mirabilis. In this study susceptibility phenotypes and genomic data of 13 OXA-48-like-producing P. mirabilis were investigated (OXA-48, n = 9; OXA-181, n = 3; OXA-162, n = 1). Ten isolates were susceptible to meropenem and ertapenem and three isolates were susceptible to piperacillin-tazobactam. The gene blaOXA-48 was chromosomally located in 7/9 isolates. Thereof, in three isolates blaOXA-48 was inserted into a P. mirabilis genomic island. Of the three isolates harbouring blaOXA-181 one was located on an IncX3 plasmid and two were located on a novel MOBF plasmid, pOXA-P12, within the new transposon Tn7713. In 5/6 isolates with plasmidic location of blaOXA-48-like, the plasmids could conjugate to E. coli recipients in vitro. Vice versa, blaOXA-48-carrying plasmids could conjugate from other Enterobacterales into a P. mirabilis recipient. These data show a high diversity of blaOXA-48-like genetic environments compared to other Enterobacterales, where genetic environments are quite homogenous. Given the difficult-to-detect phenotype of OXA-48-like-producing P. mirabilis and the location of blaOXA-48-like on mobile genetic elements, it is likely that OXA-48-like-producing P. mirabilis can disseminate, escape most surveillance systems, and contribute to a hidden spread of OXA-48-like

High Prevalence of Cysticercosis in People with Epilepsy in Southern Rwanda

<div><p>Background</p><p>Neurocysticercosis (NCC), the central nervous system infection by <i>Taenia solium</i> larvae, is a preventable and treatable cause of epilepsy. In Sub-Saharan Africa, the role of NCC in epilepsy differs geographically and, overall, is poorly defined. We aimed at contributing specific, first data for Rwanda, assessing factors associated with NCC, and evaluating a real-time PCR assay to diagnose NCC in cerebrospinal fluid (CSF).</p><p>Methodology/Principal findings</p><p>At three healthcare facilities in southern Rwanda, 215 people with epilepsy (PWE) and 51 controls were clinically examined, interviewed, and tested by immunoblot for cysticerci-specific serum antibodies. Additionally, CSF samples from PWE were tested for anticysticercal antibodies by ELISA and for parasite DNA by PCR. Cranial computer tomography (CT) scans were available for 12.1% of PWE with additional symptoms suggestive of NCC. The Del Brutto criteria were applied for NCC diagnosis. Cysticerci-specific serum antibodies were found in 21.8% of PWE and 4% of controls (odds ratio (OR), 6.69; 95% confidence interval (95%CI), 1.6–58.7). Seropositivity was associated with age and lack of safe drinking water. Fifty (23.3%) PWE were considered NCC cases (definitive, based on CT scans, 7.4%; probable, mainly based on positive immunoblots, 15.8%). In CSF samples from NCC cases, anticysticercal antibodies were detected in 10% (definitive cases, 25%) and parasite DNA in 16% (definitive cases, 44%). Immunoblot-positive PWE were older (medians, 30 <i>vs.</i> 22 years), more frequently had late-onset epilepsy (at age >25 years; 43.5% <i>vs.</i> 8.5%; OR, 8.30; 95%CI, 3.5–20.0), and suffered from significantly fewer episodes of seizures in the preceding six months than immunoblot-negative PWE.</p><p>Conclusions/Significance</p><p>NCC is present and contributes to epilepsy in southern Rwanda. Systematic investigations into porcine and human cysticercosis as well as health education and hygiene measures for <i>T. solium</i> control are needed. PCR might provide an additional, highly specific tool in NCC diagnosis.</p></div