Evaluation of the mycobacteria MBT kit for identification of nontuberculous mycobacteria by MALDI-TOF Biotyper (Bruker).

Identification of mycobacteria is crucial for clinical management of patients. The new MBT Mycobacteria kit from the Easy MycoEx protocol (Bruker) is used for the identification of mycobacteria by MALDI Biotyper. The Easy MycoEx protocol was compared to the MycoEx protocol (1) for identification of various mycobacterial isolates collected from samples in 2021, (2) for prospective identification on primary culture during 2 periods. For 44 isolates in MGIT broth, identification rates were high and similar for both protocols (98% vs 95% at cut-off 1.6 and 91% vs 82% at cut-off 1.8). For 42 mycobacteria on Coletsos agar, identification rates were 88% versus 90% at cut-off 1.6 and 76% for both protocols at cut-off 1.8. For slow-growing mycobacteria in MGIT, reproducibility of deposit results was superior with Easy MycoEx. No difference of score was observed between 2 protocols performed on primary culture. Clinical laboratories can easily implement the Easy MycoEx protocol.

[Recommendations for functional evaluation and rehabilitation of chronic low back pain]. / Recommandations pour l'évaluation et la rééducation fonctionnelles du patient souffrant d'une lombalgie chronique.

The majority of non-specific low back pain has a favourable evolution within a short period of time but in some cases the pain becomes persistent or recurrent. These chronic forms are responsible for most of the social and economic burden of low back pain. The crucial role of psycho-social factors in the chronicisation of low back pain justifies a thorough bio-psycho-social assessment. An active semi-intensive ambulatory multidisciplinary programme (Spine Unit Center) that complies with international and national recommendations (KCE and INAMI) has demonstrated its effectiveness in chronic low back pain in terms of algo-functional, physical and psycho-social components. In contrast to intensive programmes requiring hospitalisation, this outpatient treatment allows the patient to remain in his/her social and professional network. The active participation and motivation of the patient are essential for the success of the treatment. The multidisciplinary team will help the patient to define his/her functional objectives and to manage, via the psychologist, emotional aspects. The programme includes therapeutic education and physical reconditioning sessions including progressive aerobic training, group exercises, and individualised and progressive strengthening of the trunk muscles. The introduction of physical activity at home will be encouraged in order to sustain the changes in the patient's behaviour.

La majorité des lombalgies non spécifiques présente une évolution favorable dans un délai assez court, mais, dans certains cas, les douleurs deviennent persistantes ou récurrentes. Ces formes chroniques sont responsables de l'essentiel du poids social et économique des lombalgies. Le rôle crucial des facteurs psycho-sociaux dans la chronicisation de la lombalgie justifie une évaluation bio-psycho-sociale approfondie. Un programme pluridisciplinaire ambulatoire actif semi-intensif («Clinique du Dos¼) répondant aux recommandations internationales et nationales (KCE et INAMI) a démontré une efficacité sur les composantes algo-fonctionnelles, physiques et psycho-sociales du patient lombalgique chronique. Contrairement aux programmes intensifs imposant une hospitalisation, cette prise en charge ambulatoire permet au patient de rester dans son réseau social et professionnel. La participation active et la motivation du patient constituent les éléments essentiels pour la réussite du traitement. L'équipe pluridisciplinaire l'aidera à définir ses objectifs fonctionnels et à gérer, via le psychologue, certains aspects émotionnels en lien avec la douleur. Le programme comprend des séances d'éducation thérapeutique et de reconditionnement physique, incluant un entraînement aérobie progressif, une gymnastique collective de tonification et un renforcement individualisé et graduel des muscles du tronc. L'instauration d'une activité physique à domicile sera encouragée de manière à pérenniser les changements de comportement du patient.

Effectiveness of resisted training through translation of the pelvis in chronic low back pain.

BACKGROUND: Resisted training of the trunk muscles improves outcomes in chronic low back pain (CLBP). The Itensic b-effect machine was designed to provide resisted training through posterior translation of the pelvis in a seated, forward-tilted position, in contrast with traditional machines that involve extension of the trunk. OBJECTIVE: To study the effectiveness of lumbopelvic training on the Itensic b-effect machine in individuals with CLBP. METHODS: Participants were allocated to 4 weeks of either progressive Itensic (I) training in addition to an education/exercise (EE) program (I+EE group, n= 23) or the education/exercise program alone (EE group, n= 22). PRIMARY OUTCOME: Roland Morris Disability Questionnaire (RMDQ). SECONDARY OUTCOMES: pain (0-10 numeric rating scale), trunk extensor endurance (Sorensen test), motor control (thoraco-lumbar dissociation test) and mobility (finger-to-floor test). RESULTS: RMDQ score improved more in the I+EE group than in the EE group (with a between-group difference at the pos-test). Pain and mobility improved in the I+EE group only, motor control improved in both groups with no between-group difference and the Sorensen test did not improve significantly in either group. CONCLUSIONS: Resisted posterior pelvic translation using the Itensic machine in addition to an education/exercise program improved disability, pain and mobility more than the education/exercise program alone.

Impact of EUCAST rapid antimicrobial susceptibility testing (RAST) on management of Gram-negative bloodstream infection.

OBJECTIVES: During bloodstream infections, reducing the time to antimicrobial susceptibility testing is crucial to initiation of early appropriate antibiotic therapy. For Gram-negative infections, a phenotypic approach remains necessary. Rapid antimicrobial testing (RAST) is a recently developed phenotypic EUCAST method. The goal of this study was to evaluate the accuracy and clinical impact of RAST. PATIENTS AND METHODS: From September 2020 to August 2021, Gram-negative episodes with positive blood culture detected in the morning were included in the RAST group. Categorical agreement of RAST with conventional antimicrobial testing on strains was determined. To assess antibiotic management and patient outcomes, the RAST group was compared with a control group (CG) with positive blood culture detected in the afternoon for which overnight antimicrobial testing was performed. RESULTS: The RAST group included 61 episodes from 61 patients, while the CG group included 49 episodes from 48 patients. While RAST performed on 41 E. coli, 11 K. pneumoniae and 9 P. aeruginosa strains highlighted 99.3 % of categorical agreement, 7.4 % of unreadable zones and 9.4 % of technical uncertainty area at 4 h incubation were also reported. For the RAST group, effective antibiotic therapy was prescribed in 100 % of patients on the day of positive blood culture (day 1) vs 88 % in CG (p = 0,007). As for beta-lactams on day 1, RAST led to 9 escalations and 6 de-escalations. Mortality and length of hospital stay did not significantly differ between the two groups. CONCLUSION: RAST improves management of antibiotic therapy in patients with Gram-negative sepsis.

Distribution of Achromobacter Species in 12 French Cystic Fibrosis Centers in 2020 by a Retrospective MALDI-TOF MS Spectrum Analysis.

Achromobacter spp. are nonfermenting Gram-negative bacilli mainly studied among cystic fibrosis (CF) patients. The identification of the 19 species within the genus is time-consuming (nrdA-sequencing), thus data concerning the distribution of the species are limited to specific studies. Recently, we built a database using MALDI-TOF mass spectrometry (MS) (Bruker) that allows rapid and accurate species identification and detection of the multiresistant epidemic clones: A. xylosoxidans ST137 spreading among CF patients in various French and Belgium centers, and A. ruhlandii DES in Denmark. Here, we first assessed whether species identification could be achieved with our database solely by analysis of MS spectra without availability of isolates. Then, we conducted a multicentric study describing the distribution of Achromobacter species and of the clone ST137 among French CF centers. We collected and analyzed with our local database the spectra of Achromobacter isolates from 193 patients (528 samples) from 12 centers during 2020. In total, our approach enabled to conclude for 502/528 samples (95.1%), corresponding to 181 patients. Eleven species were detected, only five being involved in chronic colonization, A. xylosoxidans (86.4%), A. insuavis (9.1%), A. mucicolens (2.3%), A. marplatensis (1.1%) and A. genogroup 3 (1.1%). This study confirmed the high prevalence of A. xylosoxidans in chronic colonizations and the circulation of the clone A. xylosoxidans ST137 in France: four patients in two centers. The present study is the first to report the distribution of Achromobacter species from CF patients samples using retrospective MALDI-TOF/MS data. This easy approach could enable future large-scale epidemiological studies.

Matrix-Assisted Laser Desorption Ionization-Time of Flight Mass Spectrometry for Rapid Detection of Isolates Belonging to the Epidemic Clones Achromobacter xylosoxidans ST137 and Achromobacter ruhlandii DES from Cystic Fibrosis Patients.

Achromobacter spp. are increasingly reported among cystic fibrosis patients. Genotyping requires time-consuming methods such as multilocus sequence typing or pulsed-field gel electrophoresis. Therefore, data on the prevalence of multiresistant epidemic clones, especially A. xylosoxidans ST137 (AxST137) and the Danish epidemic strain A. ruhlandii (DES), are lacking. We recently developed and published a database for Achromobacter species identification by matrix-assisted laser desorption-ionization-time of flight mass spectrometry (MALDI-TOF MS; Bruker Daltonics). The aim of this study was to evaluate the ability of the MALDI-TOF MS to distinguish these multiresistant epidemic clones within Achromobacter species. All the spectra of A. xylosoxidans (n = 1,571) and A. ruhlandii (n = 174) used to build the local database were analyzed by ClinProTools, MALDI Biotyper PCA, MALDI Biotyper dendrogram, and flexAnalysis software for biomarker peak detection. Two hundred two isolates (including 48 isolates of AxST137 and 7 of DES) were tested. Specific biomarker peaks were identified: absent peak at m/z 6,651 for AxST137 isolates and present peak at m/z 9,438 for DES isolates. All tested isolates were well typed by our local database and clustered within distinct groups (ST137 or non-ST137 and DES or non-DES) no matter the MALDI-TOF software or only by simple visual inspection of the spectra by any user. The use of MALDI-TOF MS allowed us to identify isolates of A. xylosoxidans belonging to the AxST137 clone that spread in France and Belgium (the Belgian epidemic clone) and of A. ruhlandii belonging to the DES clone. This tool will help the implementation of segregation measures to avoid interpatient transmission of these resistant clones.

Sputum versus nasopharyngeal samples for the molecular diagnosis of respiratory viral infection in cystic fibrosis: A pilot study.

Viruses are important agents in lung function deterioration in Cystic Fibrosis (CF). To date, no standard operating procedures (SOPs) have been established to determine which sampling method is the most effective for an optimal virological diagnosis of respiratory viral infections in CF. Here we investigated the performances of two sampling sites, sputum samples versus nasopharyngeal (NP) swabs, for thirty participants from three CF centres presenting an acute respiratory infection. Sputum and NP samples were simultaneously collected and multiplex PCR targeting 16 to 18 viruses were performed. Viruses were detected for 18/30 patients (60%). A high concordance between the sputum and NP samples was observed in 25 (83%) paired samples of which 13 tested positive and 12 tested negative. These results highlighted the relevance of sputum sampling for diagnostic of respiratory viruses in CF, which is less invasive and better accepted by CF patients than NP, and allows accurate bacterial detection.

Rapid identification of fungi from respiratory samples by Bruker Biotyper matrix-assisted laser desorption/ionisation time-of-flight using ID-FUNGI plates.

Identification of moulds is crucial for the clinical management of patients. The goal of this study was to evaluate the new ID-FUNGI plate (IDFP) for the identification of moulds by MALDI Biotyper. IDFP was compared with Sabouraud with gentamicin and chloramphenicol plate (SAB) for the identification of 80 moulds from respiratory samples and eight reference strains. With the direct transfer method, species identification rose from 6% with SAB to 68% with IDFP using score cut-off 2 and from 20 to 75% using cut-off 1.7 (p < 0.001). Our study highlights that the new IDFP improves mycological diagnostic and workflow in laboratories.

[Contribution and evolution of blood culture quality indicators]. / Apports et perspectives d'évolution des indicateurs qualité de l'hémoculture.

The monitoring of quality indicators, combined with a detailed risk analysis, validates the process of automated blood culture. Here we report the methodology of 5 years monitoring for 5 indicators at the Biology Department of Foch Hospital: volume sampled, proportion of contaminants, proportion of positive blood cultures in each instrument and drawer, epidemiological indicator and proportion of false-positive instrument signals. The results obtained were outside the expected target for the volume sampled and were acceptable for the other indicators. The analysis of these results leads us to discuss the evolution of quality indicators and more particularly the implementation of corrective measures, their periodicity, their relevance as well as the need to refine their results to carry out targeted actions.

Mutations in epilepsy and intellectual disability genes in patients with features of Rett syndrome.

Rett syndrome and neurodevelopmental disorders with features overlapping this syndrome frequently remain unexplained in patients without clinically identified MECP2 mutations. We recruited a cohort of 11 patients with features of Rett syndrome and negative initial clinical testing for mutations in MECP2. We analyzed their phenotypes to determine whether patients met formal criteria for Rett syndrome, reviewed repeat clinical genetic testing, and performed exome sequencing of the probands. Using 2010 diagnostic criteria, three patients had classical Rett syndrome, including two for whom repeat MECP2 gene testing had identified mutations. In a patient with neonatal onset epilepsy with atypical Rett syndrome, we identified a frameshift deletion in STXBP1. Among seven patients with features of Rett syndrome not fulfilling formal diagnostic criteria, four had suspected pathogenic mutations, one each in MECP2, FOXG1, SCN8A, and IQSEC2. MECP2 mutations are highly correlated with classical Rett syndrome. Genes associated with atypical Rett syndrome, epilepsy, or intellectual disability should be considered in patients with features overlapping with Rett syndrome and negative MECP2 testing. While most of the identified mutations were apparently de novo, the SCN8A variant was inherited from an unaffected parent mosaic for the mutation, which is important to note for counseling regarding recurrence risks.

Progenitor "Mycobacterium canettii" clone responsible for lymph node tuberculosis epidemic, Djibouti.

"Mycobacterium canettii," an opportunistic human pathogen living in an unknown environmental reservoir, is the progenitor species from which Mycobacterium tuberculosis emerged. Since its discovery in 1969, most of the ≈70 known M. canettii strains were isolated in the Republic of Djibouti, frequently from expatriate children and adults. We show here, by whole-genome sequencing, that most strains collected from February 2010 through March 2013, and associated with 2 outbreaks of lymph node tuberculosis in children, belong to a unique epidemic clone within M. canettii. Evolution of this clone, which has been recovered regularly since 1983, may mimic the birth of M. tuberculosis. Thus, recognizing this organism and identifying its reservoir are clinically important.

Effects of subinhibitory concentrations of antibiotics on virulence factor expression by community-acquired methicillin-resistant Staphylococcus aureus.

OBJECTIVES: To examine the effect of subinhibitory concentrations (sub-MICs) of antistaphylococcal drugs on Panton-Valentine leucocidin (PVL), α-haemolysin (Hla) and protein A (SpA) expression by community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA). METHODS: Five clinical isolates representing the main worldwide CA-MRSA clones were grown with sub-MICs (1/8, 1/4 and 1/2 MIC) of five antibiotics (clindamycin, daptomycin, linezolid, tigecycline and vancomycin). After 4 and 6 h of incubation, culture pellets were used for relative quantitative RT-PCR with primers specific for pvl, hla, spa and gyrB. The PVL, Hla and SpA concentrations were measured in the supernatant (for PVL and Hla) and in the cell pellet (for SpA) using specific ELISAs. RESULTS: For all strains tested, clindamycin and linezolid dramatically reduced mRNA levels of PVL and SpA. Tigecycline also decreased the PVL and SpA mRNA levels of 3/5 and 4/5 strains tested, respectively, whereas daptomycin and vancomycin had no significant effect. PVL and SpA quantification confirmed the concentration-dependent inhibition of PVL and SpA production by clindamycin and, to a lesser extent, by linezolid and tigecycline. Only clindamycin decreased Hla mRNA expression, whereas linezolid, tigecycline and daptomycin showed heterogeneous strain-dependent results, and vancomycin had no significant effect. Analysis of the Hla level revealed a stronger concentration-dependent inhibition of Hla release by clindamycin than by linezolid. CONCLUSIONS: The effect of sub-MICs on virulence expression depended on the antibiotic and the virulence factor. Clindamycin and linezolid consistently suppressed the expression of different virulence factors by CA-MRSA, whereas tigecycline specifically suppressed PVL expression. Daptomycin and vancomycin seem to have no significant effects at these concentrations.

SLC25A22 is a novel gene for migrating partial seizures in infancy.

OBJECTIVE: To identify a genetic cause for migrating partial seizures in infancy (MPSI). METHODS: We characterized a consanguineous pedigree with MPSI and obtained DNA from affected and unaffected family members. We analyzed single nucleotide polymorphism 500K data to identify regions with evidence of linkage. We performed whole exome sequencing and analyzed homozygous variants in regions of linkage to identify a candidate gene and performed functional studies of the candidate gene SLC25A22. RESULTS: In a consanguineous pedigree with 2 individuals with MPSI, we identified 2 regions of linkage, chromosome 4p16.1-p16.3 and chromosome 11p15.4-pter. Using whole exome sequencing, we identified 8 novel homozygous variants in genes in these regions. Only 1 variant, SLC25A22 c.G328C, results in a change of a highly conserved amino acid (p.G110R) and was not present in control samples. SLC25A22 encodes a glutamate transporter with strong expression in the developing brain. We show that the specific G110R mutation, located in a transmembrane domain of the protein, disrupts mitochondrial glutamate transport. INTERPRETATION: We have shown that MPSI can be inherited and have identified a novel homozygous mutation in SLC25A22 in the affected individuals. Our data strongly suggest that SLC25A22 is responsible for MPSI, a severe condition with few known etiologies. We have demonstrated that a combination of linkage analysis and whole exome sequencing can be used for disease gene discovery. Finally, as SLC25A22 had been implicated in the distinct syndrome of neonatal epilepsy with suppression bursts on electroencephalogram, we have expanded the phenotypic spectrum associated with SLC25A22.

Ceftobiprole efficacy in vitro against Panton-Valentine leukocidin production and in vivo against community-associated methicillin-resistant Staphylococcus aureus osteomyelitis in rabbits.

Community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) can cause osteomyelitis with severe sepsis and/or local complications in which a Panton-Valentine leukocidin (PVL) role is suspected. In vitro sub-MIC antibiotic effects on growth and PVL production by 11 PVL(+) MRSA strains, including the major CA-MRSA clones (USA300, including the LAC strain; USA400; and USA1000), and 11 PVL(+) methicillin-susceptible S. aureus (MSSA) strains were tested in microplate culture. Time-kill analyses with ceftobiprole at its MIC were also run with LAC. Efficacies of ceftobiprole (40 mg/kg of body weight subcutaneously [s.c.] four times a day [q.i.d.]) or vancomycin (60 mg/kg intramuscularly [i.m.] twice a day [b.i.d.]) alone or combined with rifampin (10 mg/kg b.i.d.) against rabbit CA-MRSA osteomyelitis, induced by tibial injection of 3.4 × 10(7) CFU of LAC, were compared. Treatment, started 14 days postinoculation, lasted 14 days. In vitro, 6/11 strains cultured with sub-MICs of ceftobiprole produced 1.6- to 4.8-fold more PVL than did the controls, with no link to specific clones. Rifampin decreased PVL production by all tested strains. In time-kill analyses at the LAC MIC (0.75 mg/liter), PVL production rose transiently at 6 and 8 h and then declined 2-fold at 16 h, concomitant with a 2-log(10)-CFU-count decrease. In vivo, the mean log(10) CFU/g of bone for ceftobiprole (1.44 ± 0.40) was significantly lower than that for vancomycin (2.37 ± 1.22) (P = 0.034), with 7/10 versus 5/11 bones sterilized, respectively. Combination with rifampin enhanced ceftobiprole (1.16 ± 0.04 CFU/g of bone [P = 0.056], 11/11 sterile bones) and vancomycin (1.23 ± 0.06 CFU/g [P = 0.011], 11/11 sterile bones) efficacies. Ceftobiprole bactericidal activity and the rifampin anti-PVL effect could play a role in these findings, which should be of interest for treating CA-MRSA osteomyelitis.

Development and biomechanical testing of a new osteosynthesis plate (TCP) designed to stabilize mandibular condyle fractures.

INTRODUCTION: In this paper, the different steps of development and experimental validation of a new type of three-dimensional (3-D) trapezoidal osteosynthesis plate (Modus TCP 2.0, Medartis, Basel, Switzerland) is described. These plates have been designed to stabilize sub-condylar and condylar neck fractures of the mandible. MATERIAL AND METHODS: In order to apply the principles of functionally stable osteosynthesis to the mandibular condyle, i.e. to put the plate as close as possible to the tensile strain lines occurring during function, two new 4- and 9-hole 3-D trapezoidal plates were designed. Tests were conducted on fresh human mandibles before and after osteosynthesis of a standardised unilateral sub-condylar 'fracture', and a static biting exercise between the ipsilateral first molars was reproduced on a test bench. The resulting condylar fragment displacement in the sagittal plane was measured and the alterations of the condylar tensile strain lines induced by the osteosynthesis were investigated by using photoelastic strain tests. RESULTS: None of the plates broke. No macroscopic condylar displacement was noted when assessing the quality of the primary stabilization. Strain analysis showed the ability of these 3-D plates to transmit physiological strains across the fracture line and the absence of potentially damaging strains around the plate. DISCUSSION: These results were accredited to the 3-D and trapezoidal features of the plates. CONCLUSION: The Modus TCP plates experimentally fulfil the principles of functionally stable osteosynthesis in the condylar region and are able to resist physiological strains.