Composition and changes of blood microbiota in adult patients with community-acquired sepsis: A pilot study from bench to bedside

BackgroundCharacteristics of the blood microbiota among adult patients with community-acquired sepsis are poorly understood. Our aim was to analyze the composition of blood microbiota in adult patients with community-acquired sepsis, and correlate changes with non-septic control patients.MethodsA prospective observational study was carried out by including adult patients hospitalized for community-acquired sepsis at our center between January and November 2019, by random selection from a pool of eligible patients. Study inclusion was done on the day of sepsis diagnosis. Community acquisition was ascertained by a priori exclusion criteria; sepsis was defined according to the SEPSIS-3 definitions. Each included patient was matched with non-septic control patients by age and gender in a 1:1 fashion enrolled from the general population. Conventional culturing with BacT/ALERT system and 16S rRNA microbiota analysis were performed from blood samples taken in a same time from a patient. Abundance data was analyzed by the CosmosID HUB Microbiome software.ResultsAltogether, 13 hospitalized patients were included, 6/13 (46.2%) with sepsis and 7/13 (53.8%) with septic shock at diagnosis. The most prevalent etiopathogen isolated from blood cultures was Escherichia coli, patients mostly had intraabdominal septic source. At day 28, all-cause mortality was 15.4% (2/13). Compared to non-septic control patients, a relative scarcity of Faecalibacterium, Blautia, Coprococcus and Roseburia genera, with an abundance of Enhydrobacter, Pseudomonas and Micrococcus genera was observed among septic patients. Relative differences between septic vs. non-septic patients were more obvious at the phylum level, mainly driven by Firmicutes (25.7% vs. 63.1%; p<0.01) and Proteobacteria (36.9% vs. 16.6%; p<0.01). The alpha diversity, quantified by the Chao1 index showed statistically significant difference between septic vs. non-septic patients (126 ± 51 vs. 66 ± 26; p<0.01). The Bray-Curtis beta diversity, reported by principal coordinate analysis of total hit frequencies, revealed 2 potentially separate clusters among septic vs. non-septic patients.ConclusionIn adult patients with community-acquired sepsis, specific changes in the composition and abundance of blood microbiota could be detected by 16S rRNA metagenome sequencing, compared to non-septic control patients. Traditional blood culture results only partially correlate with microbiota test results

Investigation of Delafloxacin Resistance in Multidrug-Resistant Escherichia coli Strains and the Detection of E. coli ST43 International High-Risk Clone

Delafloxacin is a novel fluoroquinolone agent that is approved for clinical application. In this study, we analyzed the antibacterial efficacy of delafloxacin in a collection of 47 Escherichia coli strains. Antimicrobial susceptibility testing was performed by the broth microdilution method and minimum inhibitory concentration (MIC) values were determined for delafloxacin, ciprofloxacin, levofloxacin, moxifloxacin, ceftazidime, cefotaxime, and imipenem. Two multidrug-resistant E. coli strains, which exhibited delafloxacin and ciprofloxacin resistance as well as extended-spectrum beta-lactamase (ESBL) phenotype, were selected for whole-genome sequencing (WGS). In our study, delafloxacin and ciprofloxacin resistance rates were 47% (22/47) and 51% (24/47), respectively. In the strain collection, 46 E. coli were associated with ESBL production. The MIC50 value for delafloxacin was 0.125 mg/L, while all other fluoroquinolones had an MIC50 value of 0.25 mg/L in our collection. Delafloxacin susceptibility was detected in 20 ESBL positive and ciprofloxacin resistant E. coli strains; by contrast, E. coli strains that exhibited a ciprofloxacin MIC value above 1 mg/L were delafloxacin-resistant. WGS analysis on the two selected E. coli strains (920/1 and 951/2) demonstrated that delafloxacin resistance is mediated by multiple chromosomal mutations, namely, five mutations in E. coli 920/1 (gyrA S83L, D87N, parC S80I, E84V, and parE I529L) and four mutations in E. coli 951/2 (gyrA S83L, D87N, parC S80I, and E84V). Both strains carried an ESBL gene, blaCTX-M-1 in E. coli 920/1 and blaCTX-M-15 in E. coli 951/2. Based on multilocus sequence typing, both strains belong to the E. coli sequence type 43 (ST43). In this paper, we report a remarkable high rate (47%) of delafloxacin resistance among multidrug-resistant E. coli as well as the E. coli ST43 international high-risk clone in Hungary

Comparison of Streptococcus mutans strains from children with caries-active, caries-free and gingivitis clinical diagnosis by pulsed-field gel electrophoresis

A study was conducted to compare the DNA structure of Streptococcus mutans strains in children with caries-active, caries-free, and gingivitis clinical diagnosis. Twenty-eight Streptococcus mutans strains from 100 children’s plaques were examined by pulsed-field gel electrophoresis (PFGE) method. The classified strains were closely related to one another, though the strains originated from different disease groups. Three identical pairs were found, but the pairs in two cases belonged to different disease groups.The results of the PFGE experiments suggest that there is no correlation between the different DNA patterns of S. mutans strains and their cariogenecity. So the different DNA strains of S. mutans are not the only determining factor in the development of dental caries

Felnőttek központi idegrendszeri tuberkulózisa = Central nervous system tuberculosis in adult patients

A központi idegrendszeri tuberkulózis az ötödik leggyakoribb, egyben legsúlyosabb lefolyású extrapulmonalis tuberkulózisforma. A nem specifikus tünetekkel kezdődő kórkép korai diagnózisa és a terápia elkezdése kulcsfontosságú a betegség kimenetele szempontjából. A szerzők egy esetismertetés és tizenöt beteg kórtörténetének retrospektív feldolgozása által mutatják be a kórkép jellemzőit, összefoglalják a diagnosztikus és terápiás lehetőségeket. Betegek és módszerek: 1998. január 1. és 2009. szeptember 1. között az Egyesített Szent István és Szent László Kórház Neuroinfektológiai Osztályán 15 központi idegrendszeri tuberkulózissal kezelt beteg orvosi dokumentációinak elemzése történt meg retrospektív módon. Eredmények: A betegek átlagéletkora 54,5 év, 40%-uk nő volt. A kezdeti kémiai liquorparaméterek emelkedett fehérjét [1,54 g/l; 95%-os konfidenciaintervallum (KI): 1,01–2,05] és sejtszámot (átlag: 337/μl; KI: 171,9–502,5), csökkent cukorindexet (0,32; KI: 0,15–0,52) mutattak. A betegek 93,3%-ánál (15/14 beteg) hyponatraemiát észleltünk. Átlagosan 16,3 (1–40) napos kezdeti panaszokkal érkeztek a betegek. Fizikális vizsgálattal kilenc betegnél (60%) meningealis izgalmi jeleket nem lehetett észlelni. Fejfájás és tudatzavar 53%-ban, míg fejfájás, láz, tarkókötöttség együttesen 33,3%-ban volt jelen felvételkor. Az esetek 46,7%-ában támasztotta alá a diagnózist tenyésztés és/vagy a polimerázláncreakció-vizsgálat. A betegek kétharmadát tudták követni legalább egy éven át, kilenc betegnél tapasztaltak neurológiai maradványtünetet. A szerzők megállapították, hogy kezdetben jellegtelen tünetek vezetik be a betegséget, amelyhez később progrediáló tudatzavar, agyidegbénulás, konvulziók társulhatnak. A betegek között a fejfájás és alterált tudat bizonyult vezető tünetnek. A diagnosztikában az arany standard eljárás ma is a tenyésztés szilárd és folyékony táptalajon. A polimeráz láncreakciós módszer érzékenysége átlagosan 27–85%-os. A korai diagnózishoz segít a hajlamosító tényezők (immunhiány, HIV-fertőzés, korábbi tbc-expozíció) feltérképezése. A négyes kombinációban alkalmazott gátlószeres kezelés 12 hónapig való alkalmazása a betegeket meggyógyította, de még a korán felismert és megfelelően kezelt megbetegedések esetén is változó súlyosságú idegrendszeri maradványtünetekkel, esetenként halállal kell számolni. Következtetések: A központi idegrendszeri tuberkulózis ritka, de rendszeresen előforduló, jellegtelen tünetegyüttessel jelentkező kórkép, aminek felismerése nehéz. Minden szubakut jellegű, fejfájással, tudatzavarral, emelkedett liquorfehérjével és alacsony liquorcukorértékkel járó betegség kapcsán a központi idegrendszeri tuberkulózisnak szerepelnie kell differenciáldiagnosztikai gondolkodásunkban. Orv. Hetil., 2011, 152, 588–596. | Central nervous system tuberculosis is the fifth most frequent and at the same time most severe form of extrapulmonary tuberculosis diseases. It presents with no typical signs, thus early diagnosis and treatment is of high importance concerning the outcome. Authors present the characteristics, diagnostic and therapeutic alternatives of central nervous system tuberculosis through a case report and a retrospective study of 15 patients. Patients and methods: Authors performed a retrospective analysis of medical records of patients with central nervous system tuberculosis in an academic teaching hospital (Department of Neurology and Infectious Diseases, United Szent István-Szent László Hospital, Budapest, Hungary). Results: Median age of patients was 54.5 years, and 6 (40%) were females. Cerebrospinal fluid findings at admission showed elevated protein (1.54 g/l; 95% confidence interval (CI): 1.01–2.05), cell count (mean: 337/μl; CI: 171.9–502.5), and decreased glucose index (0.32; CI: 0.15–0.52). 14 patients (93.3%) had hyponatremia. Average duration of symptoms were 16.3 days (1–40). On physical examination meningeal irritation was absent in 9 patients (60%). On admission headache and altered consciousness was present in 53%, while headache, fever, nuchal rigidity was present in only 33.3%. Diagnosis was culture and/or PCR confirmed in 46.7% of the cases. Two third of patients were followed-up at least for one year, and nine patients presented neurological sequel. Authors found that patients with central nervous system tuberculosis present with unspecific symptoms, but later progressive disorientation, cranial nerve palsies and convulsions may develop. Headache and altered consciousness proved to be the leading symptoms among these patients. Even today, diagnostic gold standard procedure is cultivating M. tuberculosis on solid and liquid medium. The polymerase chain reaction, which is known to have sensitivity between 27% and 86%, was positive in two of eight samples. Revealing predisposing factors (immunodeficiency, HIV infection, previous tuberculosis exposure) promotes setting up early diagnosis. Co-administration of four antituberculotic drugs for 12 months cured all patients, but authors note that even in cases with early diagnosis and optimal treatment various neurological impairment and seldom death can occur. Conclusions: Central nervous system tuberculosis is a rare but regularly emerging disease with unspecific signs and symptoms. The diagnosis may be difficult. It should be considered as a differential diagnostic issue in patients with uncharacteristic subacute conditions with headache, disorientation, elevated protein and low glucose in cerebrospinal fluid. Orv. Hetil., 2011, 152, 588–596

A multicentre evaluation of the NG-test DetecTool OXA-23 for the rapid detection of OXA-23 carbapenemase directly from blood cultures

Objectives: A multicentre study evaluating NG-Test DetecTool OXA-23 for the detection of OXA-23 carbapenemase directly from positive blood cultures (PBCs). Methods: The NG-Test DetecTool OXA-23 is an immunoassay that integrates a sample preparation device. We evaluated NG-Test DetecTool OXA-23 on 189 spiked and 126 clinical PBCs. The clinical samples' standard-of-care procedure consisted of bacterial identification from the first day of positivity by MALDI-TOF MS, conventional culture and antimicrobial susceptibility testing. The immunoassay results were verified molecularly. The strains used for the spiked samples consisted of well-characterized Acinetobacter baumannii and Proteus mirabilis strains. Results: The NG-Test DetecTool OXA-23 was evaluated on 315 PBCs and revealed sensitivity of 100% (95% CI: 98.21%-100.00%) and specificity of 100% (95% CI: 96.73%-100.00%). It provided 204 true-positive results for OXA-23 in 196 bottles with carbapenem-resistant A. baumannii (CRAB) and 8 bottles with carbapenem-resistant P. mirabilis and also provided 111 true-negative results. There were no false-positive and no false-negative results. Among the 315 PBCs studied, 83 clinical blood cultures collected in the ICU of a Greek university hospital, which were tested prospectively, all yielded CRAB, and OXA-23 was correctly detected in all samples from the first day of positivity using the NG-Test DetecTool OXA-23. Conclusions: The NG-Test DetecTool OXA-23 has exhibited excellent sensitivity and specificity for OXA-23 detection in PBCs and can provide valuable information for appropriate selection of antibiotic therapy and early implementation of infection control measures

Rapid detection of CTX-M-type ESBLs and carbapenemases directly from biological samples using the BL-DetecTool

International audienceAbstract Background Lateral flow immunoassays (LFIA) have shown their usefulness for detecting CTX-M- and carbapenemase-producing Enterobacterales (CPEs) in bacterial cultures. Here, we have developed and validated the BL-DetecTool to detect CTX-M enzymes and carbapenemases directly from clinical samples. Methods The BL-DetecTool is an LFIA that integrates an easy sample preparation device named SPID (Sampling, Processing, Incubation and Detection). It was evaluated in three University hospitals on urine, blood culture (BC) and rectal swab (RS) specimens either of clinical origin or on spiked samples. RS evaluation was done directly and after a 24 h enrichment step. Results The CTX-M BL-DetecTool was tested on 485 samples (154 BC, 150 urines, and 181 RS) and revealed a sensitivity and specificity of 97.04% (95% CI 92.59%–99.19%) and 99.43% (95% CI 97.95%–99.93%), respectively. Similarly, the Carba5 BL-DetecTool was tested on 382 samples (145 BC, 116 urines, and 121 RS) and revealed a sensitivity and specificity of 95.3% (95% CI 89.43%–98.47%) and 100% (95% CI 98.67%–100%), respectively. While with the Carba5 BL-DetecTool five false negatives were observed, mostly in RS samples, with the CTX-M BL-DetecTool, in addition to four false-negatives, two false-positives were also observed. Direct testing of RS samples revealed a sensitivity of 78% and 86% for CTX-M and carbapenemase detection, respectively. Conclusions BL-DetecTool showed excellent biological performance, was easy-to-use, rapid, and could be implemented in any microbiology laboratory around the world, without additional equipment, no need for electricity, nor trained personnel. It offers an attractive alternative to costly molecular methods

A multicentre evaluation of the NG-test DetecTool OXA-23 for the rapid detection of OXA-23 carbapenemase directly from blood cultures

Objectives A multicentre study evaluating NG-Test DetecTool OXA-23 for the detection of OXA-23 carbapenemase directly from positive blood cultures (PBCs). Methods The NG-Test DetecTool OXA-23 is an immunoassay that integrates a sample preparation device. We evaluated NG-Test DetecTool OXA-23 on 189 spiked and 126 clinical PBCs. The clinical samples’ standard-of-care procedure consisted of bacterial identification from the first day of positivity by MALDI-TOF MS, conventional culture and antimicrobial susceptibility testing. The immunoassay results were verified molecularly. The strains used for the spiked samples consisted of well-characterized Acinetobacter baumannii and Proteus mirabilis strains. Results The NG-Test DetecTool OXA-23 was evaluated on 315 PBCs and revealed sensitivity of 100% (95% CI: 98.21%–100.00%) and specificity of 100% (95% CI: 96.73%–100.00%). It provided 204 true-positive results for OXA-23 in 196 bottles with carbapenem-resistant A. baumannii (CRAB) and 8 bottles with carbapenem-resistant P. mirabilis and also provided 111 true-negative results. There were no false-positive and no false-negative results. Among the 315 PBCs studied, 83 clinical blood cultures collected in the ICU of a Greek university hospital, which were tested prospectively, all yielded CRAB, and OXA-23 was correctly detected in all samples from the first day of positivity using the NG-Test DetecTool OXA-23. Conclusions The NG-Test DetecTool OXA-23 has exhibited excellent sensitivity and specificity for OXA-23 detection in PBCs and can provide valuable information for appropriate selection of antibiotic therapy and early implementation of infection control measures