Risk factors for early mortality in patients with pulmonary tuberculosis admitted to the emergency room.

Abstract Background and objectives Mortality of patients with pulmonary tuberculosis (TB) admitted to emergency departments is high. This study was aimed at analysing the risk factors associated with early mortality and designing a risk score based on simple parameters. Methods This prospective case-control study enrolled patients admitted to the emergency department of a referral TB hospital. Clinical, radiological, biochemical and microbiological risk factors associated with death were compared among patients dying within one week from admission (cases) and those surviving (controls). Results Forty-nine of 250 patients (19.6%) experienced early mortality. Multiple logistic regression analysis showed that oxygen saturation (SaO2) ≤90%, severe malnutrition, tachypnoea, tachycardia, hypotension, advanced disease at chest radiography, severe anaemia, hyponatremia, hypoproteinemia and hypercapnia were independently and significantly associated with early mortality. A clinical scoring system was further designed to stratify the risk of death by selecting five simple parameters (SpO2 ≤ 90%, tachypnoea, hypotension, advanced disease at chest radiography and tachycardia). This model predicted early mortality with a positive predictive value of 94.88% and a negative predictive value of 19.90%. Conclusions The scoring system based on simple parameters may help to refer severely ill patients early to a higher level to reduce mortality, improve success rates, minimise the need for pulmonary rehabilitation and prevent post-treatment sequelae

Randomised trial to evaluate the effectiveness and safety of varying doses of linezolid with bedaquiline and pretomanid in adults with pre-extensively drug-resistant or treatment intolerant/non-responsive multidrug-resistant pulmonary tuberculosis: study protocol.

INTRODUCTION Drug-resistant tuberculosis (DR-TB) is a global public health problem. Patients suffer for months if undiagnosed or treated inadequately, transmitting DR-TB in the community before succumbing to the disease. Early diagnosis, prompt treatment initiation and completion play a significant role in treatment success. However, extended regimens with injectable result in poor treatment adherence and outcomes. Our objective is to evaluate the effectiveness, safety and tolerability of various doses and duration of linezolid (LZD) in combination with bedaquiline (BDQ) and pretomanid (Pa) after 26 weeks of treatment in adults with pre-extensively drug-resistant or treatment intolerant/non-responsive multidrug-resistant pulmonary TB. METHODS AND ANALYSIS A multicentric, randomised pragmatic clinical trial in India will enrol participants in one of the three arms-control arm (arm 1): BDQ, Pa and LZD 600 mg daily for 26 weeks or intervention arms (arm 2): BDQ, Pa and LZD 600 mg for 9 weeks followed by 300 mg for 17 weeks or arm 3: BDQ, Pa and LZD 600 mg for 13 weeks followed by 300 mg for 13 weeks. The primary endpoint is the proportion of patients with favourable outcomes as sustained cure and treatment completion. The secondary endpoint is unfavourable outcomes, including deaths, treatment failure, toxicity/adverse events and lost to follow-up till 48 weeks post-treatment. ETHICS AND DISSEMINATION The study has been approved by the ethics committees of participating institutes and the National Institute for Research in TB. The trial results will help establish evidence towards a safe and effective dose of LZD that can be used in a fully, all-oral short course regimen for highly DR-TB patients. The results of this study will be shared with the National TB Elimination Programme of the country and the WHO guidelines development group through publications and dissemination meetings. TRIAL REGISTRATION NUMBER NCT05040126

Identifying patients with multidrug-resistant tuberculosis who may benefit from shorter durations of treatment.

ObjectiveStudying treatment duration for rifampicin-resistant and multidrug-resistant tuberculosis (MDR/RR-TB) using observational data is methodologically challenging. We aim to present a hypothesis generating approach to identify factors associated with shorter duration of treatment.Study design and settingWe conducted an individual patient data meta-analysis among MDR/RR-TB patients restricted to only those with successful treatment outcomes. Using multivariable linear regression, we estimated associations and their 95% confidence intervals (CI) between the outcome of individual deviation in treatment duration (in months) from the mean duration of their treatment site and patient characteristics, drug resistance, and treatments used.ResultsOverall, 6702 patients with successful treatment outcomes from 84 treatment sites were included. We found that factors commonly associated with poor treatment outcomes were also associated with longer treatment durations, relative to the site mean duration. Use of bedaquiline was associated with a 0.51 (95% CI: 0.15, 0.87) month decrease in duration of treatment, which was consistent across subgroups, while MDR/RR-TB with fluoroquinolone resistance was associated with 0.78 (95% CI: 0.36, 1.21) months increase.ConclusionWe describe a method to assess associations between clinical factors and treatment duration in observational studies of MDR/RR-TB patients, that may help identify patients who can benefit from shorter treatment

Voltage Gated Calcium Channels Negatively Regulate Protective Immunity to Mycobacterium tuberculosis

Mycobacterium tuberculosis modulates levels and activity of key intracellular second messengers to evade protective immune responses. Calcium release from voltage gated calcium channels (VGCC) regulates immune responses to pathogens. In this study, we investigated the roles of VGCC in regulating protective immunity to mycobacteria in vitro and in vivo. Inhibiting L-type or R-type VGCC in dendritic cells (DCs) either using antibodies or by siRNA increased calcium influx in an inositol 1,4,5-phosphate and calcium release calcium activated channel dependent mechanism that resulted in increased expression of genes favoring pro-inflammatory responses. Further, VGCC-blocked DCs activated T cells that in turn mediated killing of M. tuberculosis inside macrophages. Likewise, inhibiting VGCC in infected macrophages and PBMCs induced calcium influx, upregulated the expression of pro-inflammatory genes and resulted in enhanced killing of intracellular M. tuberculosis. Importantly, compared to healthy controls, PBMCs of tuberculosis patients expressed higher levels of both VGCC, which were significantly reduced following chemotherapy. Finally, blocking VGCC in vivo in M. tuberculosis infected mice using specific antibodies increased intracellular calcium and significantly reduced bacterial loads. These results indicate that L-type and R-type VGCC play a negative role in M. tuberculosis infection by regulating calcium mobilization in cells that determine protective immunity

Screening for Tuberculosis in Migrants: A Survey by the Global Tuberculosis Network

Tuberculosis (TB) does not respect borders, and migration confounds global TB control and elimination. Systematic screening of immigrants from TB high burden settings and-to a lesser degree TB infection (TBI)-is recommended in most countries with a low incidence of TB. The aim of the study was to evaluate the views of a diverse group of international health professionals on TB management among migrants. Participants expressed their level of agreement using a six-point Likert scale with different statements in an online survey available in English, French, Mandarin, Spanish, Portuguese and Russian. The survey consisted of eight sections, covering TB and TBI screening and treatment in migrants. A total of 1055 respondents from 80 countries and territories participated between November 2019 and April 2020. The largest professional groups were pulmonologists (16.8%), other clinicians (30.4%), and nurses (11.8%). Participants generally supported infection control and TB surveillance established practices (administrative interventions, personal protection, etc.), while they disagreed on how to diagnose and manage both TB and TBI, particularly on which TBI regimens to use and when patients should be hospitalised. The results of this first knowledge, attitude and practice study on TB screening and treatment in migrants will inform public health policy and educational resources

Sequelae of pulmonary multidrug-resistant tuberculosis at the completion of treatment

Background: Treatment of multidrug-resistant (MDR-TB) mainly focuses on bacteriological cure. However, only limited studies have evaluated the sequelae left after the completion of treatment among MDR-TB patients. Objective: To assess the persistent symptoms, radiological sequelae, pulmonary function impairment and quality of life at the completion of treatment among MDR-TB patients. Methods: Forty six MDR-TB patients were enrolled, who completed two years of treatment under programmatic management of Drug Resistant tuberculosis at a tertiary referral institute in Delhi, India. Detailed clinical history was taken. X-ray chest, 6 Minute Walk Test and pulmonary function tests were attempted in all patients. Quality of life was evaluated using Seattle obstructive lung disease questionnaire. Results: At the completion of MDR-TB treatment 95.7% patients had residual symptoms; 100% patients had residual bilateral chest x-ray abnormality with 82.6% patients showing far advanced disease. PFT was abnormal in 97.6% patients with mixed pattern being the commonest abnormality. Quality of Life was impaired with mean physical function of 46%. Conclusion: At the completion of MDR-TB treatment, significant numbers of patients are left with post treatment sequelae. The medical management and social support for these patients should be incorporated in the national programs

Sequential Decision Making With Information Asymmetry (Invited Talk)

We survey some recent results in sequential decision making under uncertainty, where there is an information asymmetry among the decision-makers. We consider two versions of the problem: persuasion and mechanism design. In persuasion, a more-informed principal influences the actions of a less-informed agent by signaling information. In mechanism design, a less-informed principal incentivizes a more-informed agent to reveal information by committing to a mechanism, so that the principal can make more informed decisions. We define Markov persuasion processes and Markov mechanism processes that model persuasion and mechanism design into dynamic models. Then we survey results on optimal persuasion and optimal mechanism design on myopic and far-sighted agents. These problems are solvable in polynomial time for myopic agents but hard for far-sighted agents

Online Reinforcement Learning with Uncertain Episode Lengths

Existing episodic reinforcement algorithms assume that the length of an episode is fixed across time and known a priori. In this paper, we consider a general framework of episodic reinforcement learning when the length of each episode is drawn from a distribution. We first establish that this problem is equivalent to online reinforcement learning with general discounting where the learner is trying to optimize the expected discounted sum of rewards over an infinite horizon, but where the discounting function is not necessarily geometric. We show that minimizing regret with this new general discounting is equivalent to minimizing regret with uncertain episode lengths. We then design a reinforcement learning algorithm that minimizes regret with general discounting but acts for the setting with uncertain episode lengths. We instantiate our general bound for different types of discounting, including geometric and polynomial discounting. We also show that we can obtain similar regret bounds even when the uncertainty over the episode lengths is unknown, by estimating the unknown distribution over time. Finally, we compare our learning algorithms with existing value-iteration based episodic RL algorithms on a grid-world environment

A 46-year-old man with tracheomegaly, tracheal diverticulosis, and bronchiectasis: Mounier-Kuhn syndrome

Lower respiratory tract infection is one of the common causes of morbidity in India which is occasionally undiagnosed. In this regard tracheobronchomegaly is one of those conditions which masquerade as chronic bronchitis and bronchiectasis and are usually undiagnosed. It is a well-defined clinical and radiologic entity characterized by marked dilatation of the trachea and the central bronchi and is frequently associated with recurrent lower respiratory tract infection. Tracheobronchomegaly has been described by a variety of names, including Mounier-Kuhn syndrome, tracheal diverticulosis, tracheobronchiectasis, tracheocele, tracheomalacia, and tracheobronchopathia malacia