Higher plasma interleukin - 6 levels are associated with lung cavitation in drug-resistant tuberculosis.

BACKGROUND: Lung cavitation is associated with heightened TB transmission and poor treatment outcomes. This study aimed to determine the relationship between systemic inflammation and lung cavitation in drug-resistant TB patients with and without HIV co-infection. METHODS: Plasma samples were obtained from 128 participants from the CAPRISA 020 Individualized M(X)drug-resistant TB Treatment Strategy Study (InDEX) prior to treatment initiation. Lung cavitation was present in 61 of the 128 drug-resistant TB patients with 93 being co-infected with HIV. The plasma cytokine and chemokine levels were measured using the 27-Plex Human Cytokine immunoassay. Modified Poisson regression models were used to determine the association between plasma cytokine/chemokine expression and lung cavitation in individuals with drug-resistant TB. RESULTS: Higher Interleukin-6 plasma levels (adjusted risk ratio [aRR] 1.405, 95% confidence interval [CI] 1.079-1.829, p = 0.011) were associated with a higher risk of lung cavitation in the multivariable model adjusting for age, sex, body mass index, HIV status, smoking and previous history of TB. Smoking was associated with an increased risk of lung cavitation (aRR 1.784, 95% CI 1.167-2.729, p = 0.008). An HIV positive status and a higher body mass index, were associated with reduced risk of lung cavitation (aRR 0.537, 95% CI 0.371-0.775, p = 0.001 and aRR 0.927, 95% CI 0.874-0.983, p = 0.012 respectively). CONCLUSION: High plasma interleukin-6 levels are associated with an increased risk of cavitary TB highlighting the role of interleukin-6 in the immunopathology of drug-resistant TB.

Corrigendum: An in vitro study to elucidate the effects of Product Nkabinde on immune response in peripheral blood mononuclear cells of healthy donors.

[This corrects the article DOI: 10.3389/fphar.2024.1308913.].

An in vitro study to elucidate the effects of product Nkabinde on immune response in peripheral blood mononuclear cells of healthy donors.

Introduction: A significant number of the South African population still rely on traditional medicines (TM) as their primary healthcare due to their belief in their holistic healing and immune-boosting properties. However, little to no scientific data is available on the effects of most TM products on cytokine and cellular biomarkers of the immune response. Here, we evaluated the impact of traditional medicine [Product Nkabinde (PN)] in inducing cellular and cytokine biomarkers of inflammation in peripheral blood mononuclear cells (PBMCs) from eight healthy volunteers. Methods: PN was supplied by a local Traditional Health Practitioner (THP). The IC50 (half maximum concentration) of the standardized extract on isolated PBMCs was established using the cell viability assay over 24 h of incubation. Luminex and flow cytometry assays were used to measure cytokine and cellular levels in PBMCs stimulated with PN and/or PHA over 24, 48, and 72 h, respectively. Results: The IC50 concentration of PN in treated PBMCs was established at 325.3 µg/mL. In the cellular activation assay, the percentages of CD38-HLA-DR + on total CD4+ T cells were significantly increased in PBMCs stimulated with PN compared to unstimulated controls after 24 h (p = 0.008). PN significantly induced the production of anti-inflammatory IL-10 (p = 0.041); proinflammatory cytokines IL-1α (p = 0.003), TNF-α (p < 0.0001); and chemokine MIP-1ß (p = 0.046) compared to the unstimulated control after 24 h. At 48 h incubation, the production of proinflammatory cytokines IL-1α (p = 0.034) and TNF-α (p = 0.011) were significantly induced following treatment with PN. Conclusion: We conclude that the PN possesses in vitro immunomodulatory properties that may influence immune and inflammatory responses. More studies using PN are needed to further understand key parameters mediating induction, expression, and regulation of the immune response in the context of pathogen-associated infections.

Performance of Softcup® menstrual cup and vulvovaginal swab samples for detection and quantification of genital cytokines.

Cytokines are important mediators of immunity in the female genital tract, and their levels may be associated with various reproductive health outcomes. However, the measurement of cytokines and chemokines in vaginal fluid samples may be influenced by a variety of factors, each with the potential to affect the sensitivity and accuracy of the assay, including the interpretation and comparison of data. We measured and compared cytokine milieu in samples collected via Softcup® menstrual cup versus vulvovaginal swabs. One hundred and eighty vulvovaginal swabs from CAPRISA 088 and 42 Softcup supernatants from CAPRISA 016 cohorts of pregnant women were used to measure the concentrations of 28 cytokines through multiplexing. Cytokines measured in this study were detectable in each of the methods however, SoftCup supernatants showed consistently, higher detectability, expression ratios, and mean concentration of cytokines than vulvovaginal swabs. While mean concentrations differed, the majority of cytokines correlated between SoftCup supernatants and vulvovaginal swabs. Additionally, there were no significant differences in a number of participants between the two sampling methods for the classification of genital inflammation. Our findings suggest that SoftCup supernatants and vulvovaginal swab samples are suitable for the collection of genital specimens to study biological markers of genital inflammatory response. However, the Softcup menstrual cup performs better for the detection and quantification of soluble biomarkers that are found in low concentrations in cervicovaginal fluid.

The impact of enteral feeding and therapeutic monitoring of rifampicin with dose escalation in critically ill patients with tuberculosis.

OBJECTIVES: Critically ill patients with tuberculosis (TB) face a high mortality risk and require effective treatment. There is a paucity of data on rifampicin pharmacokinetics, the impact of continuous enteral feeding on drug absorption, and the potential of therapeutic drug monitoring (TDM) to optimize drug exposure in these patients. METHODS: We performed a sequential pharmacokinetic study to determine the impact of feeding and TDM with rifampicin dose escalation in critically ill patients with TB. Noncompartmental pharmacokinetic analysis was performed. RESULTS: Among 20 critically ill patients (40% were HIV-infected), median rifampicin Cmax (maximum serum concentration) in the fasted and fed states were 5.1 µg/ml versus 3.3 µg/ml, respectively (P <0.0001; geometric mean ratio 1.95; 90% confidence interval 1.46-2.60). The proportion of patients with low rifampicin concentrations in the fasted and fed states was 80% vs 100% (P-value = 0.1336). Optimized dosing led to a per-patient median rifampicin dosing of 24.6 mg/kg and a median Cmax increase from 2.4 µg/ml to 17.8 µg/ml (P-value = 0.0005; geometric mean ratio 8.29; 90% confidence interval 3.88-17.74). TDM-guided dose escalation increased the proportion of patients achieving the suggested target rifampicin concentration compared with standard dosing (83% vs 0%, P-value = 0.004). CONCLUSION: We found low rifampicin concentrations in all patients receiving continuous enteral feeding. TDM-guided dose escalation provided an effective strategy to achieve target drug exposure in these critically ill patients with TB.

Isoniazid resistance-conferring mutations are associated with highly variable phenotypic resistance.

Background: High-dose isoniazid is recommended in the 9-12 months short-course regimen for multidrug-resistant tuberculosis with inhA mutation. However, there is insufficient evidence to support the assumption of genotypic-phenotypic concordance. This study aimed to identify the genetic mutations associated with high-level phenotypic isoniazid resistance. Methods: Clinical isolates from patients with drug-resistant tuberculosis were profiled by whole-genome sequencing and subjected to minimum inhibitory concentration (MIC) testing using MGIT based-method. MICs were performed in concentration ranges based on the mutation present: isolates with no isoniazid resistance-conferring mutations and H37Rv, 0.016-0.256 µg/ml; inhA, 0.256-4.0 µg/ml, katG 1.0-16.0 µg/ml; and inhA + katG, 4.0-64.0 µg/ml. Isolates demonstrating resistance at the upper limit of the concentration range were tested up to the maximum of 64.0 µg/ml. Bootstrap of the mean MICs was performed to increase the robustness of the estimates and an overlap index was used to compare the distributions of the MICs for each mutation profile. Results: A total of 52 clinical isolates were included in this analysis. Bootstrap MIC means for inhA, katG and inhA + katG were 33.64 (95% CI, 9.47, 56.90), 6.79 (4.45, 9.70) and 52.34 (42.750, 61.66) µg/ml, respectively. There was high overlap between inhA and inhA + katG mutations (eta = 0.45) but not with inhA and katG (eta = 0.19). Furthermore, katG showed poor overlap with inhA + katG mutations (eta = 0.09). Unexpectedly, 4/8 (50.0%) of all InhA mutants demonstrated high-level resistance, while 20/24 (83.3%) of katG mutants demonstrated moderate-level resistance. Conclusions: InhA mutations demonstrated unexpectedly high MICs and showed high overlap with inhA + katG. Contrary to the common belief that katG mutants are associated with high-level resistance, this mutation primarily showed moderate-level resistance.

Metronidazole Treatment Failure and Persistent BV Lead to Increased Frequencies of Activated T- and Dendritic-Cell Subsets.

Metronidazole (MDZ) treatment failure and bacterial vaginosis (BV) recurrence rates are high among African women. This cohort study identified genital immune parameters associated with treatment response by comparing vaginal microbiota and immune cell frequencies in endocervical cytobrushes obtained from 32 South African women with symptomatic BV pre- and post-metronidazole treatment. Cervical T- and dendritic-cell subsets were phenotyped using multiparameter flow cytometry and the composition of vaginal microbial communities was characterized using 16S rRNA gene sequencing. MDZ treatment led to a modest decrease in the relative abundance of BV-associated bacteria, but colonization with Lactobacillus species (other than L. iners) was rare. At 6 and 12 weeks, MDZ-treated women had a significant increase in the frequencies of CCR5+ CD4+ T cells and plasmacytoid dendritic cells compared to the pre-treatment timepoint. In addition, MDZ non-responders had significantly higher frequencies of activated CD4 T cells and monocytes compared to MDZ responders. We conclude that MDZ treatment failure was characterized by an increased expression of activated T- and dendritic-cell subsets that may enhance HIV susceptibility. These data suggest the need to further assess the long-term impact of MDZ treatment on mucosal immune response and the vaginal microbiota.

Mental health outcomes and workplace quality of life among South African pharmacists during the COVID-19 pandemic: a cross-sectional study.

BACKGROUND: The effect of the COVID-19 pandemic on the mental health of healthcare workers is gaining attention globally. This study assessed the quality-of-working life (QoWL) and prevalence of, and risk factors for anxiety, depression and stress among South African pharmacists. METHODS: An online survey, after stratification by province, was sent to 3435 (target = 2454) randomly selected pharmacists between 14 April to 18 May 2021. Sociodemographic data were collected and mental health was assessed using the 7-item Generalized Anxiety Disorder scale, the 9-item Patient Health Questionnaire, Perceived Stress Scale and a modified Work-Related Quality-of-Life tool. Prevalence of anxiety, depression, stress and QoWL was estimated. A multivariate logistic regression analysis identified factors associated with mental health outcomes. RESULTS: A total of 953/2454 pharmacists (38.8%) responded. Of these, 56.5% were 40 years or younger, 78.5% were female, 45.4% were White race and 44.5% were practicing in a community pharmacy setting. Pharmacists demonstrated symptoms of anxiety (n = 605, 66.1%), depression (n = 561, 62.9%), stress (n = 642, 73.8%) and low QoWL (n = 409, 51.3%). Significant risk factors (aOR; 95%CI) for anxiety, depression and stress were female gender (1.96;1.36-2.83,1.84;1.27-2.67,1.58;1.05-2.38, history of mental health conditions (2.50; 1.52-4.13, 3.68; 2.19-6.19, 3.34;1.85-6.03) and significant COVID-19 mitigation changes to pharmacy practice (2.70; 1.36-5.38, 4.23; 2.06-8.70, 3.14;1.44-6.82), respectively. Practice changes were also associated with a low QoWL (5.19; 2.40-11.8). Compared to their Black/African colleagues, Indian pharmacists were at higher risk for anxiety (1.82; 1.03-3.23) and stress symptoms (2.28; 1.21-4.32), while risk for depression was significant amongst White pharmacists (1.86; 1.05-3.32). Pharmacists living apart from family were at significant risk for anxiety (1.66; 1.15-2.41), depression (1.52; 1.06-2.18) and low QoWL (1.60; 1.10-2.34). CONCLUSIONS: COVID-19 pandemic has had a significant negative impact on the mental health of South African pharmacists. Interventions to support the psychological well-being and improve QoWL of pharmacists are needed.

Detection of differentially culturable tubercle bacteria in sputum from drug-resistant tuberculosis patients.

Several studies described the presence of non-replicating, drug-tolerant differentially culturable tubercle bacteria (DCTB) in sputum from patients with active tuberculosis (TB). These organisms are unable to form colonies on agar but can be recovered in liquid media supplemented with culture filtrate as a source of growth factors. Herein, we undertook to investigate the response of DCTB during the treatment of individuals with drug-resistant TB. A cohort of 100 participants diagnosed with rifampicin-resistant TB were enrolled and prospectively followed to monitor response to therapy using routine culture and limiting dilution assays, supplemented with culture filtrate (CF) to quantify DCTB. Fifteen participants were excluded due to contamination, and of the remaining 85 participants, 29, 49, and 7 were infected with rifampicin mono-resistant (RMR), multidrug-resistant (MDR), or extremely drug-resistant (XDR) TB, respectively. Analysis of baseline sputum demonstrated that CF supplementation of limiting dilution assays detected notable amounts of DCTB. Prevalence of DCTB was not influenced by smear status or mycobacterial growth indicator tube time to positivity. CF devoid of resuscitation promoting factors (Rpfs) yielded a greater amount of DCTB in sputum from participants with MDR-TB compared with those with RMR-TB. A similar effect was noted in DCTB assays without CF supplementation, suggesting that CF is dispensable for the detection of DCTB from drug-resistant strains. The HIV status of participants, and CD4 count, did not affect the amount of DCTB recovered. During treatment with second-line drug regimens, the probability of detecting DCTB from sputum specimens in liquid media with or without CF was higher compared with colony forming units, with DCTB detected up to 16 weeks post treatment. Collectively, these data point to differences in the ability of drug-resistant strains to respond to CF and Rpfs. Our findings demonstrate the possible utility of DCTB assays to diagnose and monitor treatment response for drug-resistant TB, particularly in immune compromised individuals with low CD4 counts.