Guy Edward Thwaites

Adjunctive corticosteroids such as dexamethasone are recommended in tuberculous meningitis treatment, despite modest and heterogeneous survival benefit. Leukotriene A4 hydrolase ( LTA4H ) genotypes associate with distinct intracerebral inflammatory phenotypes and may determine corticosteroid response in tuberculous meningitis, with benefit observed in hyperinflammatory TT genotype but uncertain benefit in lower inflammation CC and CT genotypes. Here, in a phase 3, placebo-controlled trial of human immunodeficiency virus-negative Vietnamese adults with tuberculous meningitis, we randomized 613 LTA4H CC- and CT-genotype participants to 6–8 weeks of dexamethasone or placebo, aiming to show noninferiority of placebo (hazard ratio margin of 0.75) or its superiority. Given the significant survival benefit of dexamethasone previously seen in LTA4H TT-genotype individuals, TT-genotype participants all received open-label dexamethasone and were not randomized. A total of 89 TT-genotype participants received open-label dexamethasone. In CC- and CT-genotype participants, the primary endpoint of all-cause death or new neurological event over 12 months from randomization occurred in 108/305 (35.4%) given dexamethasone and 110/308 (35.7%) given placebo (hazard ratio of 0.99, 96% confidence interval (adjusted for multiple testing) 0.748–1.31). The number of observed primary endpoints ( n = 218) exceeded the prespecified number ( n = 184) used to calculate the trial’s sample size and power. Placebo noninferiority was not established in the CC and CT population or in individual genotype subpopulations. Benefit or heterogeneity of effect was not observed by any prespecified subgroup. In TT-genotype participants, the primary endpoint occurred in 28/89 (31.5%) participants, similar to CC and CT participants. Outcomes were not significantly better in TT-genotype participants versus CC- or CT-genotype participants. In CC- and CT-genotype participants, serious adverse events occurred in 161/305 (52.8%) dexamethasone-treated participants and 160/308 (51.9%) placebo-treated participants. In conclusion, neither noninferiority nor superiority of placebo was established in human immunodeficiency virus-negative LTA4H CC- and CT-genotype adults with tuberculous meningitis, and dexamethasone was safe. The modest and heterogeneous benefit of dexamethasone indicates that greater understanding of tuberculous meningitis pathophysiology is needed, alongside better targeted, more effective anti-inflammatory agents than corticosteroids (ClinicalTrials.gov NCT03100786 ).

Background: Early diagnosis of tuberculous meningitis (TBM) is critical to favorable outcomes. We investigated whether a 3-gene host response signature in whole blood can distinguish TBM from symptomatic controls in children. Methods: Whole-blood RNA sequencing was performed in children with TBM and controls. Expression of the 3-gene signature, [guanylate-binding protein (GBP5), dual specificity phosphatase 3 (DUSP3) and Krupple-like factor 2 (KLF2)] was quantified and a tuberculosis (TB) score was calculated using (GBP5+DUSP3)/2-KLF2. Discriminatory performance was obtained using receiver-operator characteristic curve analysis against microbiologic and composite reference standards. TB score and 3-gene expression in children were compared against adults with TBM. In parallel, an exploratory transcriptome-wide analysis was performed, applying bootstrapped least absolute shrinkage and selection operator regression to identify additional genes associated with TBM. Results: Forty-two children had TBM and 41 were controls. KLF2 was upregulated in TBM compared to controls ( P = 0.043); while GBP5, DUSP3 and TB score showed no difference. The diagnostic performance of GBP5 alone (area under the curves: 0.64; 95% confidence interval: 0.46–0.83) and TB score (area under the curves: 0.59; 95% confidence interval: 0.41–0.77) was poor against the reference standard of definite TBM. GBP5 in children with TBM was lower than in adults without HIV (median 13.04; interquartile ranges: 11.91–14.29 vs. median 13.72; interquartile ranges: 12.58–14.53, P = 0.036), and expression was nonlinear across the age spectrum; lowest in young children. Exploratory transcriptomic analysis suggests that novel genes may contribute a discriminatory signal. Conclusion: The 3-gene host response signature does not discriminate TBM from controls in children and was much less discriminative compared to adults. An alternative set of pediatric-specific signatures may exist, but further discovery and validation are required.

SUMMARY: Background: The Randomised Evaluation of COVID-19 Therapy (RECOVERY) trial evaluated the effects of sixteen potential treatments for patients hospitalised with COVID-19. Dexamethasone (at a dose of 6mg daily), tocilizumab, baricitinib, and the monoclonal antibodies casirivimab-imdevimab and sotrovimab were shown to reduce 28-day mortality in all or specific groups of patients. Here we report the long-term efficacy and safety of all sixteen therapies. Methods: Patients hospitalised with COVID-19 were potentially eligible to join this randomised, controlled, open-label, platform trial. Participants were randomly allocated to receive each trial treatment, or not, on top of usual care. Analyses were by intention to treat comparing each treatment with its own usual care control group. The pre-specified primary long-term follow-up outcome was 6-month all-cause mortality, presented as mortality rate ratios adjusted for baseline age and ventilation status. The key safety outcomes were major non-COVID infection and non-COVID death at 6 months. ISRCTN50189673 and NCT04381936 . Findings: Between 19 March 2020 and 19 March 2024, 48,402 patients were included in RECOVERY COVID-19 treatment comparisons. For each of the treatments previously demonstrated to be effective at 28 days, the early mortality benefit was preserved up to 6 months. Among 6425 patients in the dexamethasone (6mg daily) comparison, 6-month mortality was 34.3% vs 44.4% in the invasive mechanical ventilation group (rate ratio [RR] 0.68; 95% confidence interval [CI] 0.55–0.85; p=0.0006); 27.7% vs 29.2% in the oxygen or non-invasive ventilation group (RR 0.87; 95% CI 0.77–0.99; p=0.034); and 26.1% vs 22.5% in the no oxygen group (RR 1.10; 95% CI 0.89–1.36; p=0.39); test for trend p=0.0024. Among 4116 patients in the tocilizumab comparison, 34.3% vs 38.9% died within 6 months (RR 0.87; 95% CI 0.79–0.96; p=0.0077). Among 8156 patients in the baricitinib comparison, 15.7% vs. 16.6% died (RR 0.89; 95% CI 0.80–0.99; p=0.032). Among 3153 anti-SARS-CoV-2 serum antibody negative patients (the primary analysis population) in the casirivimab-imdevimab comparison, 29.3% vs. 34.7% died (RR 0.87; 95% CI 0.77–0.98; p=0.024). Among 720 patients with high serum nucleocapsid antigen concentration (the primary analysis population) in the sotrovimab comparison, 33.0% vs. 38.6% died (RR 0.78; 95% CI 0.61–1.00; p=0.050). In line with the 28-day results, aspirin, azithromycin, colchicine, convalescent plasma, dimethyl fumarate, empagliflozin, lopinavir-ritonavir, molnupiravir, and nirmatrelvir-ritonavir did not reduce 6-month mortality. Mortality at 6 months was higher with hydroxychloroquine therapy (33.3% vs. 30.2%; RR 1.14; 95% CI 1.02–1.27; p=0.018) and, among hypoxic patients not requiring ventilatory support, with higher dose dexamethasone (initial dose 20mg daily, 22.0% vs. 17.6%, RR 1.34; 95% CI 1.04–1.72; p=0.021). Allocation to dexamethasone 6mg once daily resulted in a small increase in major non-COVID infection within 6 months compared with usual care (21.4% vs. 19.1%; absolute difference 2.2%; 95% CI 0.2–4.5%). We found no evidence that any other treatments increased the risk of major non-COVID infection. Interpretation: In patients hospitalised with COVID-19, dexamethasone (at a dose of 6mg daily in hypoxic patients), tocilizumab (in hypoxic patients with CRP ≥75 mg/L), baricitinib, casirivimab-imdevimab (in seronegative patients), and sotrovimab (in high antigen patients) reduced 6-month mortality. Dexamethasone at a dose of 6mg daily was associated with an increase in major non-COVID infection but there was no evidence of other later emerging harms. Other treatments tested in RECOVERY did not reduce 6-month mortality. Funding: UK Research and Innovation (Medical Research Council) and National Institute for Health and Care Research (Grant ref: MC_PC_19056), and Wellcome Trust (Grant Ref: 222406/Z/20/Z).

Immune and clinical outcomes to Mycobacterium tuberculosis (Mtb) infection vary greatly between individuals, yet the underlying genetic and cellular mechanisms driving this heterogeneity remain poorly understood. We performed a cellular genome-wide association study to identify genetic variants associated with Mtb-induced monocyte transcriptional expression of IL1B , IL6 , TNF , and IFNB1 via RNA-Seq in a Ugandan cohort. Significantly associated variants were assessed for transferability in an independent Seattle cohort, further validated in vitro, and assessed for clinical phenotype associations. We identified 77 loci suggestively associated with Mtb-induced cytokine expression in monocytes in Uganda. SNPs associated with Mtb-induced TNF were enriched within α-linolenic acid metabolism pathway genes, which was validated in vitro using PLA2 inhibitors. Four loci maintained significant associations in Seattle. We validated a cytokine effect with siRNA knockdown for two of these loci, which mapped to the genes SLIT3 and SLC1A1 . Furthermore, exogenous treatment of macrophages with SLIT3 enhanced Mtb intracellular replication. Finally, SLC1A1 and SLIT3 variants were associated with susceptibility to tuberculous meningitis and subsequent survival, respectively, in a Vietnamese cohort. In summary, we identified multiple variants and pathways associated with Mtb-induced cytokine transcriptional responses that were validated in vitro and were associated with clinical tuberculosis susceptibility.

Background: Nontuberculous mycobacteria are environmental mycobacteria that rarely cause human disease, especially in the central nervous system. Central nervous system infection by Mycobacterium avium complex, the most common pathogen among nontuberculous mycobacteria species, is rare and seldom reported, even in those with advanced human immunodeficiency virus infection. We describe a case of Mycobacterium avium complex meningitis with cerebral hemorrhage in an human immunodeficiency virus uninfected man in Vietnam. Case presentation: A 56-year-old Vietnamese man with hypertension was hospitalized with a 5-day history of headache, dizziness, low-grade fever, and unresponsive to 5 days of oral antibiotics. A brain magnetic resonance imaging, performed on day 12, showed hydrocephalus and lacunar infarct. The patient did not improve with 8 days of empirical treatment with ceftriaxone, vancomycin, dexamethasone, and meropenem, and was transferred to a referral hospital for tropical diseases. At the second hospital admission, a cerebrospinal fluid analysis showed a white cell count of 22,518 cells/μL with 81% neutrophils, protein 1.72 g/L, and glucose 0.85 mmol/L. Acid-fast bacilli smear of the cerebrospinal fluid was positive. Molecular testing of the cerebrospinal fluid was negative on GeneXpert Ultra testing, while the line probe assay was positive for Mycobacterium avium. Blood cultures at two sites, cerebrospinal fluid cultures for bacteria and fungi, and human immunodeficiency virus Ag/Ab test were negative. The patient was continuously administered meropenem with the addition of azithromycin, rifampin, and ethambutol. Then, 1 day after nontuberculous mycobacteria treatment, he developed right-sided hemiplegia, and brain computed tomography showed a hemorrhage in the parietal area, adjacent to the left lateral ventricle, and left lateral intraventricular hemorrhage shifts the midline to the right. He was transferred to the third referral general hospital and died 22 days after the onset of symptoms. Conclusion: Nontuberculous mycobacteria-central nervous system infection might mimic unresponsive pyogenic bacterial meningitis. A rapid and accurate diagnosis is essential for initiating appropriate therapy for this deadly disease.

Background Collecting and storing large number of sputum samples with a view to culturing these in the future requires an efficient initial handling method. We devised a modified sputum digestion and decontamination method that maximised storage capacity and Mycobacterium tuberculosis (M.tb) recovery from culture while minimising laboratory workload and risk of contamination. Methods We collected smear microscopy positive sputum samples from patients with pulmonary tuberculosis (TB). The sputum samples were split and processed using both the standard N-Acetyl-L-cysteine and sodium hydroxide (NALC-NaOH) method and our modified method before freezing and later culturing in BD BACTEC 960 Mycobacterium Growth Indicator Tubes (MGIT) system. We assessed the Time to Positivity (TPP) and Growth Unit (GU) data. Results We selected 22 sputum samples to compare two digestion and decontamination methods. The samples that underwent the modified method had longer TTP (p < 0.05) but similar GU in comparison to standard method. Overall, 1/22 samples failed to grow in MGIT after being processed by the modified method. We then applied the modified method to 348 sputum samples with Rifampicin resistance detected by GeneXpert MTB/RIF assay, which were frozen for between 1–25 months. The overall MGIT positive, negative, and contamination rate was 90.5%, 7.8%, and 1.7%, respectively. There was no significant difference in MGIT result when samples were grouped by duration of storage or positive smear grade. Conclusions Our modified method yielded acceptable M.tb recovery rate and low contamination risk while allowing us to collect and store thousands of sputum samples over a long period of time for future tests.

Tuberculous meningitis (TBM) is the most severe form of tuberculosis. Corticosteroids are currently recommended as an adjunctive therapy in HIV-negative adults with TBM. However, benefit from corticosteroids in TBM may depend upon host leukotriene A4 hydrolase (LTA4H) genotype and the corresponding inflammatory phenotypes. This article describes the planned analyses for the primary publication of the results of the LAST ACT clinical trial (NCT03100786): ‘Leukotriene A4 hydrolase Stratified Trial of Adjunctive Corticosteroids for HIV-negative adults with Tuberculous meningitis’. The primary hypothesis addressed by the trial is that LTA4H genotype, in particular CC or CT genotype, determines whether adjunctive dexamethasone benefits or harms adults with TBM. The trial was an LTA4H genotype stratified, parallel group, randomised, double blind, placebo-controlled multi-centre Phase III trial of dexamethasone given for 6–8 weeks in addition to standard anti-tuberculosis drugs. LTA4H genotype (CC, CT, TT) was determined in all participants prior to randomisation; only those with CC or CT genotype were randomised to dexamethasone or placebo. All TT genotype participants received dexamethasone because prior data indicated survival was increased by dexamethasone in this genotype. The primary endpoint was all-cause death or new neurological event over the first 12 months after randomisation. We took a hybrid trial-design approach which aims to prove non-inferiority of placebo first but also allows claiming superiority of placebo in case dexamethasone causes substantial harm. This statistical analysis plan expands upon and updates the analysis plan outlined in the published study protocol.