The role of familial factors and neuroticism in the association between exposure to offensive behaviors at work and long-term sickness absence due to common mental disorders - a prospective twin study.

OBJECTIVES: The aim of this study was to investigate associations between exposure to work-related violence/threats and harassment, and future sickness absence (SA) due to common mental disorders (CMDs), taking familial factors (shared genetics and early-life environment) and neuroticism into account. METHODS: The study sample included 8795 twin individuals from the Swedish Twin Project of Disability Pension and Sickness Absence (STODS), including survey data from the Study of Twin Adults: Genes and Environment (STAGE). Self-reported work-related violence and/or threats as well as work-related harassment (including bullying) and national register data on SA due to CMDs were analyzed using standard logistic regression, and conditional logistic regression among complete twin pairs discordant on exposures. Individuals were followed for a maximum of 13 years. Interactions between neuroticism and exposures were assessed using both multiplicative and additive interaction analyses. RESULTS: Exposure to work-related violence/threats was associated with higher odds of SA due to CMDs when adjusting for age, sex, marital status, children, education, type of living area, work characteristics, and symptoms of depression and burnout (OR 2.11, 95% CI 1.52-2.95). Higher odds of SA due to CMDs were also found for exposure to harassment (OR 1.52, 95% CI 1.10-2.11) and a combined indicator of exposure to violence/threats and/or harassment (OR 1.98, 95% CI 1.52-2.59), compared with the unexposed. Analyses of twins discordant on exposure, using the unexposed co-twin as reference, showed reduced ORs. These ORs were still elevated but no longer statistically significant, potentially due to a lack of statistical power. No multiplicative interaction was found between neuroticism and exposure to work-related violence/threats, or harassment. However, a statistically significant additive interaction was found between neuroticism and exposure to violence/threats, indicating higher odds of SA due to CMDs in the group scoring lower on neuroticism. CONCLUSIONS: Exposure to work-related offensive behaviors was associated with SA due to CMDs. However, the results indicated that these associations may be partly confounded by familial factors. In addition, an interaction between exposure and neuroticism was suggested. Thus, when possible, future studies investigating associations and causality between offensive behaviors at work and mental health-related outcomes, should consider familial factors and neuroticism.

Exposure to work-related violence and/or threats of violence as a predictor of certified sickness absence due to mental disorders: a prospective cohort study of 16,339 Swedish men and women in paid work.

OBJECTIVES: The aim of this prospective cohort study was to investigate if exposure to work-related violence and/or threats of violence predict certified sickness absence due to mental disorders. METHODS: Information on work-related exposure to violence and/or threats of violence were derived from the biannual Swedish Longitudinal Occupational Survey of Health (SLOSH) study 2012-2016, including individuals in paid work across Sweden and from different occupations/sectors (n = 16,339). Certified sickness absence due to mental disorders were ascertained from register data from the Swedish Social Insurance Agency. Odds ratios of certified sickness absence due to mental disorders according to exposure to work-related violence were estimated using multiple logistic regression. Several potential confounding variables, such as demographic and socio-economic factors, age, sex, cohabitation, children living at home, socio-economic status, educational level, as well as other types of psychosocial work environmental factors, were adjusted for in the analyses. RESULTS: In the total study sample, 9% reported exposure to violence and/or threats of violence and the prevalence of sickness absence due to mental disorders was 5%. Exposure to work-related violence and/or threats of violence was associated prospectively with certified sickness absence due to mental disorders (odds ratio 1.46, 95% confidence interval 1.17-1.82, p < 0.01). Analysis of possible interaction showed no difference in association when comparing women to men and different age groups. CONCLUSIONS: Exposure to work-related violence and/or threats of violence appear to increase the odds of certified sickness absence due to mental disorders. Preventive measures aiming to lower the risk of exposure is thus of great importance.

Ancient and recent differences in the intrinsic susceptibility of Mycobacterium tuberculosis complex to pretomanid.

OBJECTIVES: To develop a robust phenotypic antimicrobial susceptibility testing (AST) method with a correctly set breakpoint for pretomanid (Pa), the most recently approved anti-tuberculosis drug. METHODS: The Becton Dickinson Mycobacterial Growth Indicator Tube™ (MGIT) system was used at six laboratories to determine the MICs of a phylogenetically diverse collection of 356 Mycobacterium tuberculosis complex (MTBC) strains to establish the epidemiological cut-off value for pretomanid. MICs were correlated with WGS data to study the genetic basis of differences in the susceptibility to pretomanid. RESULTS: We observed ancient differences in the susceptibility to pretomanid among various members of MTBC. Most notably, lineage 1 of M. tuberculosis, which is estimated to account for 28% of tuberculosis cases globally, was less susceptible than lineages 2, 3, 4 and 7 of M. tuberculosis, resulting in a 99th percentile of 2 mg/L for lineage 1 compared with 0.5 mg/L for the remaining M. tuberculosis lineages. Moreover, we observed that higher MICs (≥8 mg/L), which probably confer resistance, had recently evolved independently in six different M. tuberculosis strains. Unlike the aforementioned ancient differences in susceptibility, these recent differences were likely caused by mutations in the known pretomanid resistance genes. CONCLUSIONS: In light of these findings, the provisional critical concentration of 1 mg/L for MGIT set by EMA must be re-evaluated. More broadly, these findings underline the importance of considering the global diversity of MTBC during clinical development of drugs and when defining breakpoints for AST.

Genotypic Resistance of Pyrazinamide but Not Minimum Inhibitory Concentration Is Associated With Longer Time to Sputum Culture Conversion in Patients With Multidrug-resistant Tuberculosis.

BACKGROUND: Pyrazinamide (PZA) resistance in multidrug-resistant tuberculosis (MDR-TB) is common; yet, it is not clear how it affects interim and treatment outcomes. Although rarely performed, phenotypic drug susceptibility testing (pDST) is used to define PZA resistance, but genotypic DST (gDST) and minimum inhibitory concentration (MIC) could be beneficial. We aimed to assess the impact of PZA gDST and MIC on time to sputum culture conversion (SCC) and treatment outcome in patients with MDR-TB. METHODS: Clinical, microbiological, and treatment data were collected in this cohort study for all patients diagnosed with MDR-TB in Sweden from 1992-2014. MIC, pDST, and whole-genome sequencing of the pncA, rpsA, and panD genes were used to define PZA resistance. A Cox regression model was used for statistical analyses. RESULTS: Of 157 patients with MDR-TB, 56.1% (n = 88) had PZA-resistant strains and 49.7% (n = 78) were treated with PZA. In crude and adjusted analysis (hazard ratio [HR], 0.49; 95% conficence interval [CI], .29-.82; P = .007), PZA gDST resistance was associated with a 29-day longer time to SCC. A 2-fold decrease in dilutions of PZA MIC for PZA-susceptible strains showed no association with SCC in crude or adjusted analyses (HR, 0.98; 95% CI, .73-1.31; P = .89). MIC and gDST for PZA were not associated with treatment outcome. CONCLUSIONS: In patients with MDR-TB, gDST PZA resistance was associated with a longer time to SCC. Rapid PZA gDST is important to identify patients who may benefit from PZA treatment.

Minimum Inhibitory Concentrations of Fluoroquinolones and Pyrazinamide Susceptibility Correlate to Clinical Improvement in Multidrug-resistant Tuberculosis Patients: A Nationwide Swedish Cohort Study Over 2 Decades.

BACKGROUND: Minimum inhibitory concentration (MIC) testing, unlike routine drug susceptibility testing (DST) at a single critical concentration, quantifies drug resistance. The association of MICs and treatment outcome in multidrug-resistant (MDR)-tuberculosis patients is unclear. Therefore, we correlated MICs of first- and second-line tuberculosis drugs with time to sputum culture conversion (tSCC) and treatment outcome in MDR-tuberculosis patients. METHODS: Clinical and demographic data of MDR-tuberculosis patients in Sweden, including DST results, were retrieved from medical records from 1992 to 2014. MIC determinations were performed retrospectively for the stored individual Mycobacterium tuberculosis (Mtb) isolates using broth microdilution in Middlebrook 7H9. We fitted Cox proportional hazard models correlating MICs, DST results, and clinical variables to tSCC and treatment outcome. RESULTS: Successful treatment outcome was observed in 83.5% (132/158) of MDR-tuberculosis patients. Increasing MICs of fluoroquinolones, diabetes, and age >40 years were significantly associated with unsuccessful treatment outcome. Patients treated with pyrazinamide (PZA) had a significantly shorter tSCC compared to patients who were not (median difference, 27 days). CONCLUSIONS: Increasing MICs of fluoroquinolones were correlated with unsuccessful treatment outcome in MDR-tuberculosis patients. Further studies, including MIC testing and clinical outcome data to define clinical Mtb breakpoints, are warranted. PZA treatment was associated with shorter tSCC, highlighting the importance of PZA DST.

Detection of Mycobacterium tuberculosis pncA Mutations by the Nipro Genoscholar PZA-TB II Assay Compared to Conventional Sequencing.

Pyrazinamide (PZA) is a standard component of first-line treatment regimens for Mycobacterium tuberculosis and is included in treatment regimens for drug-resistant M. tuberculosis whenever possible. Therefore, it is imperative that susceptibility to PZA be assessed reliably prior to the initiation of therapy. Currently available growth-based PZA susceptibility tests are time-consuming, and results can be inconsistent. Molecular tests have been developed for most first-line antituberculosis drugs; however, a commercial molecular test is not yet available for rapid detection of PZA resistance. Recently, a line probe assay, the Nipro Genoscholar PZA-TB II assay, was developed for the detection of mutations within the pncA gene, including the promoter region, that are likely to lead to PZA resistance. The sensitivity and specificity of this assay were evaluated by two independent laboratories, using a combined total of 249 strains with mutations in pncA or its promoter and 21 strains with wild-type pncA Overall, the assay showed good sensitivity (93.2% [95% confidence interval, 89.3 to 95.8%]) and moderate specificity (91.2% [95% confidence interval, 77.0 to 97.0%]) for the identification of M. tuberculosis strains predicted to be resistant to PZA on the basis of the presence of mutations (excluding known PZA-susceptible mutations) in the pncA coding region or promoter. The assay shows promise for the molecular prediction of PZA resistance.

Progression of clinical tuberculosis is associated with a Th2 immune response signature in combination with elevated levels of SOCS3.

In this study, we explored the local cytokine/chemokine profiles in patients with active pulmonary or pleural tuberculosis (TB) using multiplex protein analysis of bronchoalveolar lavage and pleural fluid samples. Despite increased pro-inflammation compared to the uninfected controls; there was no up-regulation of IFN-γ or the T cell chemoattractant CCL5 in the lung of patients with pulmonary TB. Instead, elevated levels of IL-4 and CCL4 were associated with high mycobacteria-specific IgG titres as well as SOCS3 (suppressors of cytokine signaling) mRNA and progression of moderate-to-severe disease. Contrary, IL-4, CCL4 and SOCS3 remained low in patients with extrapulmonary pleural TB, while IFN-γ, CCL5 and SOCS1 were up-regulated. Both SOCS molecules were induced in human macrophages infected with Mycobacterium tuberculosis in vitro. The Th2 immune response signature found in patients with progressive pulmonary TB could result from inappropriate cytokine/chemokine responses and excessive SOCS3 expression that may represent potential targets for clinical TB management.

In vitro activity of AZD5847 against geographically diverse clinical isolates of Mycobacterium tuberculosis.

The MIC of the novel antituberculosis (anti-TB) drug AZD5847 was determined against 146 clinical isolates from diverse geographical regions, including eastern Europe, North America, Africa, and Asia, using the automated Bactec Mycobacterial Growth Indicator Tube (MGIT) 960 system. These isolates originated from specimen sources such as sputum, bronchial alveolar lavage fluid, pleural fluid, abscess material, lung biopsies, and feces. The overall MIC90 was 1.0 mg/liter (range, 0.125 to 4 mg/liter). The MICs of AZD5847 for isolates of Mycobacterium tuberculosis were similar among drug-sensitive strains, multidrug-resistant (MDR) strains, and extensively drug resistant (XDR) strains. The good in vitro activity of AZD5847 against M. tuberculosis and the lack of cross-resistance make this agent a promising anti-TB drug candidate.

In vitro activity of new combinations of ß-lactam and ß-lactamase inhibitors against the Mycobacterium tuberculosis complex.

As meropenem-clavulanic acid is recommended for the treatment of drug-resistant tuberculosis, the repurposing of new carbapenem combinations may provide new treatment options, including oral alternatives. Therefore, we studied the in vitro activities of meropenem-vaborbactam, meropenem-clavulanic acid, and tebipenem-clavulanic acid. One hundred nine Mycobacterium tuberculosis complex (MTBC) clinical isolates were tested, of which 69 were pan-susceptible and the remaining pyrazinamide- or multidrug-resistant. Broth microdilution MICs were determined using the EUCAST reference method. Meropenem and tebipenem were tested individually and in combination with vaborbactam 8 mg/L and clavulanic-acid 2 and 4 mg/L, respectively. Whole-genome sequencing was performed to explore resistance mechanisms. Clavulanic acid lowered the modal tebipenem MIC approximately 16-fold (from 16 to 1 mg/L). The modal meropenem MIC was reduced twofold by vaborbactam compared with an approximately eightfold decrease by clavulanic acid. The only previously described high-confidence carbapenem resistance mutation, crfA T62A, was shared by a subgroup of lineage 4.3.4.1 isolates and did not correlate with elevated MICs. The presence of a ß-lactamase inhibitor reduced the MTBC MICs of tebipenem and meropenem. The resulting MIC distribution was lowest for the orally available drugs tebipenem-clavulanic acid. Whether this in vitro activity translates to similar or greater clinical efficacy of tebipenem-clavulanic acid compared with the currently WHO-endorsed meropenem-clavulanic acid requires clinical studies. IMPORTANCE Repurposing of already approved antibiotics, such as ß-lactams in combination with ß-lactamase inhibitors, may provide new treatment alternatives for drug-resistant tuberculosis. Meropenem-clavulanic acid was more active in vitro compared to meropenem-vaborbactam. Notably, tebipenem-clavulanic acid showed even better activity, raising the potential of an all-oral treatment option. Clinical data are needed to investigate whether the better in vitro activity of tebipenem-clavulanic acid correlates with greater clinical efficacy compared with the currently WHO-endorsed meropenem-clavulanic acid.

Multicentre testing of the EUCAST broth microdilution reference method for MIC determination on Mycobacterium tuberculosis.

OBJECTIVES: The first objective of the European Committee on Antimicrobial Susceptibility Testing (EUCAST) subcommittee for antimycobacterial susceptibility testing (AMST), launched in 2016, was to set a reference method for determining the MICs of antituberculous agents, since many protocols are used worldwide and a consensus one is needed for the determination of microbiological breakpoints. METHODS: During 2017 and 2018, MIC determination protocols were evaluated prospectively in a multicentre study within the four AMST laboratories. MIC results were obtained for isoniazid, levofloxacin and amikacin on the reference strain Mycobacterium tuberculosis H37Rv ATCC 27294. Broth microdilution (BMD) in Middlebrook 7H9 and solid medium dilution (SMD) in Middlebrook 7H10 were performed using two inoculum concentrations. MICs were interpreted with regard to visual and 99% inhibition after 7, 14 or 21 days of incubation for BMD and 21 days for SMD. RESULTS: Following the EUCAST reference protocol, intra- and inter-assay agreements were within ±1 MIC dilution for >95% of the observations for the three drugs in both methods. MIC values, presented as MIC mode (range) for BMD and SMD respectively, were: 0.03 (0.015-0.06) mg/L and 0.12 (0.06-0.25) mg/L for isoniazid, 0.25 mg/L (0.25-0.5) and 0.5 mg/L (0.12-0.5) for levofloxacin, and 0.5 mg/L (0.5-1.0) and 0.5 mg/L (0.5-1.0) for amikacin. CONCLUSIONS: Both SMD and BMD were reproducible and eligible as a reference method for MIC determination of the Mycobacterium tuberculosis complex (MTBC). BMD was finally selected as the EUCAST reference method. From now on it will be used to set epidemiological cut-off values and clinical breakpoints of new and old antituberculous agents.

Antimicrobial susceptibility testing of Mycobacterium tuberculosis complex isolates - the EUCAST broth microdilution reference method for MIC determination.

SCOPE: Several methods are used worldwide for antibiotic susceptibility testing (AST) for the Mycobacterium tuberculosis complex (MTBC). The variability in the results obtained with these methods hampers setting epidemiological cut-off (ECOFF) values and clinical breakpoints according to EUCAST guidelines. Methods for susceptibility testing and determination of the minimal inhibitory concentrations (MICs) need to be standardized for MTBC isolates for old and new agents. Our objective was to establish a standardized reference method for MIC determination for MTBC. METHODS: The EUCAST antimycobacterial susceptibility testing subcommittee (AMST) compared protocols of MIC determination with regard to medium, inoculum preparation, antituberculous agent preparation, incubation, reading of the results and interpretation. RECOMMENDATIONS: The EUCAST reference method of MIC determination for MTBC is the broth microdilution method in Middlebrook 7H9-10% OADC medium. The final inoculum is a 105 CFU/mL suspension, obtained from a 10-2 dilution of a 0.5 McFarland suspension prepared after vortexing bacterial colonies with glass beads before suspending them in sterile water. The culture is maintained in a U-shaped 96-well polystyrene microtitre sterile plate with a lid incubated at 36° ± 1°C. Reading is done using an inverted mirror as soon as the 1:100 diluted control (i.e. 103 CFU/mL suspension) shows visual growth. The MIC, expressed in mg/L, is the lowest concentration that inhibits visual growth. Mycobacterium tuberculosis H37Rv ATCC 27294 is used as the reference strain and its targeted MIC values are within the range 0.03-0.12 for isoniazid, 0.12-0.5 for levofloxacin and 0.25-1 mg/L for amikacin. CONCLUSIONS: The EUCAST reference method for MTBC was endorsed by EUCAST after public consultation and will from now on be used to define EUCAST ECOFFs and clinical breakpoints. This reference method is not primarily intended to be used under routine conditions and the AST methods will need to be calibrated against this reference method to be used with EUCAST breakpoints.

Multidrug-resistant Myobacterium tuberculosis caused by the Beijing genotype and a specific T1 genotype clone (SIT No. 266) is widely transmitted in Minsk.

SETTING: This study was performed in the city of Minsk in Belarus, where a very severe problem with MDR-TB was demonstrated in a recent drug resistant survey. OBJECTIVE: The aim of this study was to use molecular typing of MDR and pan-susceptible clinical isolates of Mycobacterium tuberculosis to increase the understanding of the transmission patterns and possible differences between the strains causing susceptible and drug-resistant tuberculosis. STUDY POPULATION AND METHODS: Consecutive isolates from pulmonary TB patients in Minsk were collected at the Belarusian National Reference Laboratory. Isolates found to be either pan-susceptible or MDR were included in the study, which totally comprised 81 MDR and 82 pan-susceptible clinical isolates. All isolates were characterized by spoligotyping. The major clusters were characterized using sequencing of the pncA gene. RESULTS: Three out of four MDR cases were caused by one out of two drug-resistant clones of M. tuberculosis belonging to the Beijing and T1 genotypes, respectively. A single T1 clone, SIT No. 266, found exclusively in the MDR cohort, was shown to cause no less than 30% of all MDR-TB cases. DISCUSSION: The findings indicate that the major cause of MDR-TB in Minsk is an ongoing transmission of certain already resistant M. tuberculosis strains. CONCLUSION: The significant transmission of MDR-TB in Minsk underlines the urgent need for strengthened infection control measures to limit the transmission in order to better control MDR-TB.