Poor Penetration of Antibiotics Into Pericardium in Pericardial Tuberculosis

A physiologically-based pharmacokinetic model for tuberculosis drug disposition at extrapulmonary sites

Tuberculosis (TB) is a leading cause of mortality attributed to an infectious agent. TB primarily targets the lungs, but in about 16% cases can affect other organs as well, giving rise to extrapulmonary TB (EPTB). However, an optimal regimen for EPTB treatment is not defined. Although the recommended treatment for most forms of EPTB is the same as pulmonary TB, the pharmacokinetics of EPTB therapy are not as well studied. To address this gap, we formulate a whole-body physiologically-based pharmacokinetic (PBPK) model for EPTB that for the first time includes the ability to simulate drug concentrations in the pleura and lymph node, the most commonly affected sites of EPTB. Using this model, we estimate the time-dependent concentrations, at potential EPTB infection sites, of the following four first-line anti-TB drugs: rifampicin, ethambutol, isoniazid, and pyrazinamide. We use reported plasma concentration kinetics data to estimate model parameters for each drug and validate our model using reported concentration data not used for model formulation or parameter estimation. Model predictions match the validation data, and reported pharmacokinetic parameters (maximum plasma concentration, time to reach maximum concentration) for the drugs. The model also predicts ethambutol, isoniazid, and pyrazinamide concentrations in the pleura that match reported experimental values from an independent study. For each drug, the predicted drug concentrations at EPTB sites are compared with their critical concentration. Simulations suggest that although rifampicin and isoniazid concentrations are greater than critical concentration values at most EPTB sites, the concentrations of ethambutol and pyrazinamide are lower than their critical concentrations at most EPTB sites.

Pervasive Selection for Clinically Relevant Resistance and Media Adaptive Mutations at Very Low Antibiotic Concentrations

Experimental evolution studies have shown that weak antibiotic selective pressures (i.e., when the antibiotic concentrations are far below the minimum inhibitory concentration, MIC) can select resistant mutants, raising several unanswered questions. First, what are the lowest antibiotic concentrations at which selection for de novo resistance mutations can occur? Second, with weak antibiotic selections, which other types of adaptive mutations unrelated to the antibiotic selective pressure are concurrently enriched? Third, are the mutations selected under laboratory settings at subMIC also observed in clinical isolates? We addressed these questions using Escherichia coli populations evolving at subMICs in the presence of either of four clinically used antibiotics: fosfomycin, nitrofurantoin, tetracycline, and ciprofloxacin. Antibiotic resistance evolution was investigated at concentrations ranging from 1/4th to 1/2000th of the MIC of the susceptible strain (MICsusceptible). Our results show that evolution was rapid across all the antibiotics tested, and selection for fosfomycin- and nitrofurantoin-resistant mutants was observed at a concentration as low as 1/2000th of MICsusceptible. Several of the evolved resistant mutants showed increased growth yield and exponential growth rates, and outcompeted the susceptible ancestral strain in the absence of antibiotics as well, suggesting that adaptation to the growth environment occurred in parallel with the selection for resistance. Genomic analysis of the resistant mutants showed that several of the mutations selected under these conditions are also found in clinical isolates, demonstrating that experimental evolution at very low antibiotic levels can help in identifying novel mutations that contribute to bacterial adaptation during subMIC exposure in real-life settings.

Comparison of the frequency and phenotypic profile of Mycobacterium tuberculosis-specific CD4 T cells between the site of disease and blood in pericardial tuberculosis

Studies of the immune response at the site of disease in extra-pulmonary tuberculosis (EPTB) disease are scarce. In this study, we compared the cellular profile of Mycobacterium tuberculosis (Mtb)-specific T cells in pericardial fluid and peripheral blood in patients with pericardial TB (PCTB). Whole blood and pericardial fluid (PCF) samples were collected at the time of diagnostic sampling, with repeat blood sampling after completion of anti-tubercular treatment (ATT) in 16 PCTB patients, most of them being HIV-1 infected (n=14). These samples were stimulated ex vivo and the phenotypic and functional cellular profile of PCF and blood was assessed by flow cytometry. We found that lymphocytes were the predominant cell type in PCF in PCTB, with a preferential influx of CD4 T cells. The frequencies of TNF-α producing Mtb-specific granulocytes and Mtb-specific CD4 T cells were significantly higher in PCF compared to blood. Mtb-specific CD4 T cells in PCF exhibited a distinct phenotype compared to those in blood, with greater GrB expression and lower CD27 and KLRG1 expression. We observed no difference in the production IFNγ, TNF or IL-2 by Mtb-specific CD4 T cells between the two compartments, but MIP-1β production was lower in the PCF T cells. Bacterial loads were not associated with alterations in the phenotype or function of Mtb-specific CD4 T cells. Upon ATT completion, HLA-DR, Ki-67 and GrB expression was significantly decreased, and relative IL-2 production was increased in peripheral Mtb-specific CD4 T cells. Overall, using an ex vivo assay to compare the immune response towards Mtb in PCF and in blood, we identified significant difference in the phenotypic profile of Mtb-specific CD4 T response between these two compartments. Moreover, we show that the activation profile of peripheral Mtb-specific CD4 T cells could be used to monitor treatment response in PCTB.

T cell responses to Mycobacterium indicus pranii immunotherapy and adjunctive glucocorticoid therapy in tuberculous pericarditis

Background

In the Investigation of the Management of Pericarditis (IMPI) randomized control, 2x2 factorial trial, Mycobacterium indicus pranii (MIP) immunotherapy, adjunctive corticosteroids or MIP combined with corticosteroids was compared to standard tuberculosis (TB) therapy for tuberculous pericarditis (TBP). While MIP and/or the combination of MIP and corticosteroids had no impact on all-cause mortality or pericarditis related outcomes, corticosteroids reduced the incidence of constrictive pericarditis at 12 months. Data suggests that both adjunctive therapies modulate the immune and inflammatory responses to pulmonary TB. Whether they affect systemic antigen-specific T cell responses, key immune mediators of Mycobacterium tuberculosis control, in patients with TBP is unknown.

Methods

Participants with definite or probable TBP were randomly assigned to receive five injections of MIP or placebo at 2-week intervals and either 6 weeks of oral prednisolone or placebo. Frequencies of CD4 and CD8 T cells expressing IFN-γ, IL-2 or TNF in response to MIP or purified protein derivative stimulation were measured by intracellular cytokine staining and flow cytometry up to 24 weeks post treatment.

Results

Immunotherapy with MIP did not significantly modulate frequencies of Th1 CD4 and CD8 T cells compared to placebo. Adjunctive prednisolone also did not change mycobacteria-specific CD4 or CD8 T cell responses. By contrast, combinatorial therapy with MIP and prednisolone was associated with a modest increase in frequencies of multifunctional and single cytokine-expressing CD4 T cell responses at 6 and 24 weeks post treatment.

Conclusions

Consistent with the lack of a significant clinical effect in the IMPI trial, MIP immunotherapy did not significantly modulate mycobacteria-specific T cell responses. Despite the positive effect of prednisolone on hospitalizations and constrictive pericarditis in the IMPI trial, prednisolone did not significantly reduce pro-inflammatory T cell responses in this sub-study. The modest improvement of mycobacteria-specific T cell upon combinatorial therapy with MIP and prednisolone requires further investigation.

Non-pulmonary Disseminated Tuberculosis Complicated by Constrictive Pericarditis and Cutaneous Gumma

A 23-year-old previously healthy male presented to the hospital with symptoms of heart failure. He was diagnosed with pericarditis and found to have a reduced left ventricular ejection fraction of 25%. He was noted to have mediastinal lymphadenopathy. Pulmonary and abdominal sampling were non-diagnostic for infection, autoimmune disease, or malignancy. A QuantiFERON Gold returned positive. After a thorough travel history and detailed exam, the patient was diagnosed with disseminated tuberculosis after the discovery of a cutaneous gumma that was found to have acid-fast bacilli present on biopsy with Fite's stain. ¹⁸F-FDG PET CT and cardiac MRI were pursued given that pericardial and myocardial biopsy could not be safely performed due to the patient's hemodynamics. ¹⁸F-FDG PET CT and cardiac MRI did not demonstrate any myocardial pathology responsible for the left ventricular ejection fraction. This case highlights that pulmonary involvement is not necessary for disseminated TB, Fite's stain may be used to identify M. tuberculosis, and that cardiac MRI and ¹⁸F-FDG PET CT may be useful to delineate myocardial involvement in high-risk situations.

The optimal duration of anti-tuberculous therapy before pericardiectomy in constrictive tuberculous pericarditis

BACKGROUND

It is unclear about the duration of anti-tuberculous therapy before pericardiectomy (DATT) in the patients with constrictive tuberculous pericarditis. This study aims to explore the optimal DATT and its impact on surgical outcomes in these patients.

METHODS

We retrospectively enrolled 93 patients with constrictive tuberculous pericarditis undergoing pericardiectomy and divided them into two groups according to the optimal cutoff value of DATT which was determined by the receiver operating characteristic (ROC) curve and Youden Index. Postoperative and survival outcomes were compared between the two groups.

RESULTS

The optimal cutoff value of DATT was 1.05 (months). The enrolled patients were divided into the DATT ≤ 1.05 group and the DATT > 1.05 group, with 24 (25.8%) and 69 (74.2%) cases, respectively. Comparing with the DATT ≤ 1.05 group, the DATT > 1.05 group had shorter postoperative ICU stay (P = 0.023), duration of chest drainage (P = 0.002), postoperative hospital stay (P = 0.001) and lower incidence of postoperative complications (P < 0.001). There were no statistical differences between the two groups in recurrence and survival outcomes.

CONCLUSIONS

It would be of potential benefit to enhance recovery after pericardiectomy if DATT lasted for at least 1 month in the patients with constrictive tuberculous pericarditis.

Clinical Pharmacokinetics and Pharmacodynamics of Rifampicin in Human Tuberculosis

The introduction of rifampicin (rifampin) into tuberculosis (TB) treatment five decades ago was critical for shortening the treatment duration for patients with pulmonary TB to 6 months when combined with pyrazinamide in the first 2 months. Resistance or hypersensitivity to rifampicin effectively condemns a patient to prolonged, less effective, more toxic, and expensive regimens. Because of cost and fears of toxicity, rifampicin was introduced at an oral daily dose of 600 mg (8-12 mg/kg body weight). At this dose, clinical trials in 1970s found cure rates of ≥ 95% and relapse rates of < 5%. However, recent papers report lower cure rates that might be the consequence of increased emergence of resistance. Several lines of evidence suggest that higher rifampicin doses, if tolerated and safe, could shorten treatment duration even further. We conducted a narrative review of rifampicin pharmacokinetics and pharmacodynamics in adults across a range of doses and highlight variables that influence its pharmacokinetics/pharmacodynamics. Rifampicin exposure has considerable inter- and intra-individual variability that could be reduced by administration during fasting. Several factors including malnutrition, HIV infection, diabetes mellitus, dose size, pharmacogenetic polymorphisms, hepatic cirrhosis, and substandard medicinal products alter rifampicin exposure and/or efficacy. Renal impairment has no influence on rifampicin pharmacokinetics when dosed at 600 mg. Rifampicin maximum (peak) concentration (C_max) > 8.2 μg/mL is an independent predictor of sterilizing activity and therapeutic drug monitoring at 2, 4, and 6 h post-dose may aid in optimizing dosing to achieve the recommended rifampicin concentration of ≥ 8 µg/mL. A higher rifampicin C_max is required for severe forms TB such as TB meningitis, with C_max ≥ 22 μg/mL and area under the concentration-time curve (AUC) from time zero to 6 h (AUC₆) ≥ 70 μg·h/mL associated with reduced mortality. More studies are needed to confirm whether doses achieving exposures higher than the current standard dosage could translate into faster sputum conversion, higher cure rates, lower relapse rates, and less mortality. It is encouraging that daily rifampicin doses up to 35 mg/kg were found to be safe and well-tolerated over a period of 12 weeks. High-dose rifampicin should thus be considered in future studies when constructing potentially shorter regimens. The studies should be adequately powered to determine treatment outcomes and should include surrogate markers of efficacy such as C_max/MIC (minimum inhibitory concentration) and AUC/MIC.

Tuberculous pericardial disease: a focused update on diagnosis, therapy and prevention of complications

Tuberculous pericarditis (TBP) is the most important manifestation of tuberculous heart disease and is still associated with a significant morbidity and mortality in TB endemic areas. The high prevalence of the disorder over the last 3 decades has been fueled by the human immunodeficiency virus/AIDS (HIV/AIDS) pandemic in these areas. The objective of this review is to provide a focused update on developments in the diagnosis and therapy of this condition, prevention of its complications, as well as future novel therapies. The definitive diagnosis of a tuberculous etiology in patients with suspected TBP continues to pose a challenge for clinicians. Clinical prediction scores, although never formally validated have been used with some success. However, they may be prone to both over and underdiagnosis due to lack of pericardial fluid analysis. Recent studies evaluating Xpert MTB/RIF, suggest that this advanced polymerase chain reaction (PCR) based technology does not provide increased accuracy compared to earlier iterations. However a combined two test approach starting with Xpert MTB/RIF followed by either adenosine deaminase (ADA) or interferon gamma (IFN-γ) may provide for significantly enhanced specificity and sensitivity cost permitting. Pericardiocentesis remains the gold standard for managing the compressive pericardial fluid and its adverse hemodynamic sequelae. A four drug anti-TB drug regimen at standard doses and duration is recommended. However recent evidence suggests that these drugs penetrate the pericardium very poorly potentially explaining the high mortality observed particularly in those who are culture positive with a high bacillary load. Constrictive pericarditis is the main long-term complication of TBP and is still a significant cause of heart failure in Sub-Saharan Africa. This is important because access to definitive surgical therapy where TBP is prevalent continues to be low, highlighting the need to develop strategies or interventions to prevent fibrosis and constriction. Recent detailed advanced studies of pericardial fluid in TBP have revealed a strong profibrotic transcriptomic profile, with high amounts of pro-inflammatory cytokines and low levels of the anti-fibrotic tetrapeptide N-Acetyl-Seryl-Aspartyl-Lysyl-Proline (Ac-SDKP). These new insights may explain in part the high propensity to fibrosis associated with the condition and offer hope for the future use of targeted therapy to interrupt pathways and mediators of tissue damage and subsequent maladaptive healing and fibrosis. The value of effective pericardiocentesis in reducing these pro-inflammatory and pro-fibrotic cytokines and peptides in an attempt to prevent pericardial constriction has yet to be established but has generated hypotheses for ongoing and future research.

The immunopathogenesis of tuberculous pericarditis

Tuberculous pericarditis is a severe form of extrapulmonary tuberculosis and is the commonest cause of pericardial effusion in high incidence settings. Mortality ranges between 8 and 34%, and it is the leading cause of pericardial constriction in Africa and Asia. Current understanding of the disease is based on models derived from studies performed in the 1940-50s. This review summarises recent advances in the histology, microbiology and immunology of tuberculous pericarditis, with special focus on the effect of Human Immunodeficiency Virus (HIV) and the determinants of constriction.

Diagnosis and Management of Tuberculous Pericarditis: What Is New?

PURPOSE OF REVIEW

This review provides an update on the immunopathogenesis of tuberculous pericarditis (TBP), investigations to confirm tuberculous etiology, the limitations of anti-tuberculous therapy (ATT), and recent efficacy trials.

RECENT FINDINGS

A profibrotic immune response characterizes TBP, with low levels of AcSDKP, high levels of γ-interferon and IL-10 in the pericardium, and high levels of TGF-β and IL-10 in the blood. These findings may have implications for future therapeutic targets. Despite advances in nucleic acid amplification approaches, these tests remain disappointing for TBP. Trials of corticosteroids and colchicine have had mixed results, with no impact on mortality, evidence of a reduction in rates of constrictive pericarditis and potential harm in those with advanced HIV. Small studies suggest that ATT penetrates the pericardium poorly. Given that there is a close association between high bacillary burden and mortality, a rethink about the optimal drug doses and duration may be required. The high mortality and morbidity from TBP despite use of anti-tuberculous drugs call for researches targeting host-directed immunological determinants of treatment outcome. There is also a need for the identification of steps in clinical management where interventions are needed to improve outcomes.

Detectable prednisolone is delayed in pericardial fluid, compared with plasma of patients with tuberculous pericarditis: A pilot study

Background

In patients with tuberculous pericarditis [TBP] adjunctive prednisolone reduces the incidence of constrictive pericarditis. It is unknown whether prednisolone permeates adequately into pericardial fluid. Drug measurements in pericardial fluid require invasive procedures, and thus less invasive methods are needed to perform full pharmacokinetic characterization of prednisolone in large numbers of patients. We sought to evaluate the relationship between prednisolone concentrations in pericardial fluid, plasma, and saliva.

Methods

Plasma, pericardial fluid, and saliva samples were collected at 7 time points from TBP patients randomized to 120 mg prednisolone or placebo. Compartmental pharmacokinetic parameters, peak concentration [C_max], and 0-24 h area under the concentration-time curve [AUC_0-24] were identified in plasma, saliva and pericardial fluid.

Results

There were five patients each in the prednisolone and placebo groups. Prednisolone concentrations were best described using a one compartment model. The absorption half-life into plasma was 1 h, while that into pericardial fluid was 9.4 h, which led to a median time-to-maximum concentration in plasma of 2.0 h versus 5.0 h in pericardial fluid [p = 0.048]. The concentration-time profiles in pericardial fluid versus plasma exhibited system hysteresis. The pericardial fluid-to-plasma C_max peak concentration ratio was 0.28 (p = 0.032), while the AUC_0-24 ratio was 0.793. The concentration-time profiles in saliva had a similar shape to those in plasma, but the saliva-to-plasma C_max was 0.59 [p = 0.032].

Conclusion

The prednisolone AUC_0-24 achieved in pericardial fluid approximates that in plasma, but the C_max is low due to delayed absorption. Saliva can be used as surrogate sampling site for pericardial fluid prednisolone.

Current research toward optimizing dosing of first-line antituberculosis treatment

Introduction: Drug concentrations in tuberculosis patients on standard regimens vary widely with clinically important consequences.

Areas covered: We review the available literature identifying factors correlated with pharmacokinetic variability of antituberculosis drugs. Based on population pharmacokinetic models and the weight, height, and sex distributions in a large data base of African tuberculosis patients, we propose simplified weight-based doses of the available fixed dose combination(FDC) for adults with drug susceptible tuberculosis. Emerging studies will support optimized weight-based dosing for children. Other sources of important pharmacokinetic variability include genetic variants, drug-drug interactions, formulation quality, and methods of preparation and administration.

Expert commentary: Optimized weight band-based dosing will result in more equitable distribution of drug exposures by weight. The use of high doses of isoniazid in patients with drug-resistant tuberculosis would be safer and more effective if a feasible test was developed to allow stratified dosing according to acetylator type. There is an urgent need for more suitable formulations of many second-line drugs for children. The adoption of new technologies and efficient FDC design may allow further advances for patients and treatment programs. Lastly, current efforts to ensure adequate quality of antituberculosis drug products are not preventing the use of substandard products to treat patients with tuberculosis.

Pharmacokinetic/Pharmacodynamic Background and Methods and Scientific Evidence Base for Dosing of Second-line Tuberculosis Drugs

A World Health Organization workshop systematically examined the evidence base for dosing second-line tuberculosis drugs, identifying knowledge gaps. To fill these in, pharmacokinetics/pharmacodynamics, Monte Carlo experiments, and artificial intelligence algorithms were used in hollow-fiber model studies and clinical data analyses.

Epidemiology of pericardial diseases in Africa: a systematic scoping review

OBJECTIVES

This scoping review sought to summarise available data on the prevalence, aetiology, diagnosis, treatment and outcome of pericardial disease in Africa.

METHODS

We searched PubMed, Scopus and African Journals Online from 1 January 1967 to 30 July 2017 to identify all studies published on the prevalence, aetiologies, diagnosis, treatment and outcomes of pericardial diseases in adults residing in Africa.

RESULTS

36 studies were included. The prevalence of pericardial diseases varies widely according to the population of interest: about 1.1% among people with cardiac complaints, between 3.3% and 6.8% among two large cohorts of patients with heart failure and up to 46.5% in an HIV-infected population with cardiac symptoms. Tuberculosis is the most frequent cause of pericardial diseases in both HIV-uninfected and HIV-infected populations. Patients with tuberculous pericarditis present mostly with effusive pericarditis (79.5%), effusive constrictive pericarditis (15.1%) and myopericarditis (13%); a large proportion of them (up to 20%) present in cardiac tamponade. The aetiological diagnosis of pericardial diseases is challenging in African resource-limited settings, especially for tuberculous pericarditis for which the diagnosis is not definite in many cases. The outcome of these diseases remains poor, with mortality rates between 18% and 25% despite seemingly appropriate treatment approaches. Mortality is highest among patients with tuberculous pericarditis especially those coinfected with HIV.

CONCLUSION

Pericardial diseases are a significant cause of morbidity and mortality in Africa, especially in HIV-infected individuals. Tuberculosis is the most frequent cause of pericardial diseases, and it is associated with poor outcomes.

Optimal Clinical Doses of Faropenem, Linezolid, and Moxifloxacin in Children With Disseminated Tuberculosis: Goldilocks

Background. When treated with the same antibiotic dose, children achieve different 0- to 24-hour area under the concentration-time curves (AUC_0–24) because of maturation and between-child physiological variability on drug clearance. Children are also infected by Mycobacterium tuberculosis isolates with different antibiotic minimum inhibitory concentrations (MICs). Thus, each child will achieve different AUC_0–24/MIC ratios when treated with the same dose.

Methods. We used 10 000-subject Monte Carlo experiments to identify the oral doses of linezolid, moxifloxacin, and faropenem that would achieve optimal target exposures associated with optimal efficacy in children with disseminated tuberculosis. The linezolid and moxifloxacin exposure targets were AUC_0–24/MIC ratios of 62 and 122, and a faropenem percentage of time above MIC >60%, in combination therapy. A linezolid AUC_0–24 of 93.4 mg × hour/L was target for toxicity. Population pharmacokinetic parameters of each drug and between-child variability, as well as MIC distribution, were used, and the cumulative fraction of response (CFR) was calculated. We also considered drug penetration indices into meninges, bone, and peritoneum.

Results. The linezolid dose of 15 mg/kg in full-term neonates and infants aged up to 3 months and 10 mg/kg in toddlers, administered once daily, achieved CFR ≥ 90%, with <10% achieving linezolid AUC_0–24 associated with toxicity. The moxifloxacin dose of 25 mg/kg/day achieved a CFR > 90% in infants, but the optimal dose was 20 mg/kg/day in older children. The faropenem medoxomil optimal dosage was 30 mg/kg 3–4 times daily.

Conclusions. The regimen and doses of linezolid, moxifloxacin, and faropenem identified are proposed to be adequate for all disseminated tuberculosis syndromes, whether drug-resistant or -susceptible.

Effect of prednisolone on inflammatory markers in pericardial tuberculosis: A pilot study

BACKGROUND

Pericardial disorders are a common cause of heart disease, and the most common cause of pericarditis in developing countries is tuberculous (TB) pericarditis. It has been shown that prednisolone added to standard anti-TB therapy leads to a lower rate of constrictive pericarditis. We conducted a pilot study to evaluate the effect of adjunctive prednisolone treatment on the concentration of inflammatory markers in pericardial tuberculosis, in order to inform immunological mechanisms at the disease site.

METHODS

Pericardial fluid, plasma and saliva samples were collected from fourteen patients with pericardial tuberculosis, at multiple time points. Inflammatory markers were measured using multiplex luminex analysis and ELISA.

RESULTS

In samples from 14 patients we confirmed a strongly compartmentalized immune response at the disease site and found that prednisolone significantly reduced IL-6 concentrations in plasma by 8 hours of treatment, IL-1beta concentrations in saliva, as well as IL-8 concentrations in both pericardial fluid and saliva by 24 hours.

CONCLUSION

Monitoring the early effect of adjunctive immunotherapy in plasma or saliva is a possibility in pericarditis.

Interventions for treating tuberculous pericarditis

BACKGROUND

Tuberculous pericarditis can impair the heart's function and cause death; long term, it can cause the membrane to fibrose and constrict causing heart failure. In addition to antituberculous chemotherapy, treatments include corticosteroids, drainage, and surgery.

OBJECTIVES

To assess the effects of treatments for tuberculous pericarditis.

SEARCH METHODS

We searched the Cochrane Infectious Diseases Group Specialized Register (27 March 2017); the Cochrane Central Register of Controlled Trials (CENTRAL), published in the Cochrane Library (2017, Issue 2); MEDLINE (1966 to 27 March 2017); Embase (1974 to 27 March 2017); and LILACS (1982 to 27 March 2017). In addition we searched the metaRegister of Controlled Trials (mRCT) and the World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP) search portal using 'tuberculosis' and 'pericard*' as search terms on 27 March 2017. We searched ClinicalTrials.gov and contacted researchers in the field of tuberculous pericarditis. This is a new version of the original 2002 review.

SELECTION CRITERIA

We included randomized controlled trials (RCTs) and quasi-RCTs.

DATA COLLECTION AND ANALYSIS

Two review authors independently screened search outputs, evaluated study eligibility, assessed risk of bias, and extracted data; and we resolved any discrepancies by discussion and consensus. One trial assessed the effects of both corticosteroid and Mycobacterium indicus pranii treatment in a two-by-two factorial design; we excluded data from the group that received both interventions. We conducted fixed-effect meta-analysis and assessed the certainty of the evidence using the GRADE approach.

MAIN RESULTS

Seven trials met the inclusion criteria; all were from sub-Saharan Africa and included 1959 participants, with 1051/1959 (54%) HIV-positive. All trials evaluated corticosteroids and one each evaluated colchicine, M. indicus pranii immunotherapy, and open surgical drainage. Four trials (1841 participants) were at low risk of bias, and three trials (118 participants) were at high risk of bias.In people who are not infected with HIV, corticosteroids may reduce deaths from all causes (risk ratio (RR) 0.80, 95% confidence interval (CI) 0.59 to 1.09; 660 participants, 4 trials, low certainty evidence) and the need for repeat pericardiocentesis (RR 0.85, 95% CI 0.70 to 1.04; 492 participants, 2 trials, low certainty evidence). Corticosteroids probably reduce deaths from pericarditis (RR 0.39, 95% CI 0.19 to 0.80; 660 participants, 4 trials, moderate certainty evidence). However, we do not know whether or not corticosteroids have an effect on constriction or cancer among HIV-negative people (very low certainty evidence).In people living with HIV, only 19.9% (203/1959) were on antiretroviral drugs. Corticosteroids may reduce constriction (RR 0.55, 0.26 to 1.16; 575 participants, 3 trials, low certainty evidence). It is uncertain whether corticosteroids have an effect on all-cause death or cancer (very low certainty evidence); and may have little or no effect on repeat pericardiocentesis (RR 1.02, 0.89 to 1.18; 517 participants, 2 trials, low certainty evidence).For colchicine among people living with HIV, we found one small trial (33 participants) which had insufficient data to make any conclusions about any effects on death or constrictive pericarditis.Irrespective of HIV status, due to very low certainty evidence from one trial, it is uncertain whether adding M. indicus pranii immunotherapy to antituberculous drugs has an effect on any outcome.Open surgical drainage for effusion may reduce repeat pericardiocentesis In HIV-negative people (RR 0.23, 95% CI 0.07 to 0.76; 122 participants, 1 trial, low certainty evidence) but may make little or no difference to other outcomes. We did not find an eligible trial that assessed the effects of open surgical drainage in people living with HIV.The review authors found no eligible trials that examined the length of antituberculous treatment needed nor the effects of other adjunctive treatments for tuberculous pericarditis.

AUTHORS' CONCLUSIONS

For HIV-negative patients, corticosteroids may reduce death. For HIV-positive patients not on antiretroviral drugs, corticosteroids may reduce constriction. For HIV-positive patients with good antiretroviral drug viral suppression, clinicians may consider the results from HIV-negative patients more relevant.Further research may help evaluate percutaneous drainage of the pericardium under local anaesthesia, the timing of pericardiectomy in tuberculous constrictive pericarditis, and new antibiotic regimens.

The epidemiology, pathogenesis, transmission, diagnosis, and management of multidrug-resistant, extensively drug-resistant, and incurable tuberculosis

Global tuberculosis incidence has declined marginally over the past decade, and tuberculosis remains out of control in several parts of the world including Africa and Asia. Although tuberculosis control has been effective in some regions of the world, these gains are threatened by the increasing burden of multidrug-resistant (MDR) and extensively drug-resistant (XDR) tuberculosis. XDR tuberculosis has evolved in several tuberculosis-endemic countries to drug-incurable or programmatically incurable tuberculosis (totally drug-resistant tuberculosis). This poses several challenges similar to those encountered in the pre-chemotherapy era, including the inability to cure tuberculosis, high mortality, and the need for alternative methods to prevent disease transmission. This phenomenon mirrors the worldwide increase in antimicrobial resistance and the emergence of other MDR pathogens, such as malaria, HIV, and Gram-negative bacteria. MDR and XDR tuberculosis are associated with high morbidity and substantial mortality, are a threat to health-care workers, prohibitively expensive to treat, and are therefore a serious public health problem. In this Commission, we examine several aspects of drug-resistant tuberculosis. The traditional view that acquired resistance to antituberculous drugs is driven by poor compliance and programmatic failure is now being questioned, and several lines of evidence suggest that alternative mechanisms-including pharmacokinetic variability, induction of efflux pumps that transport the drug out of cells, and suboptimal drug penetration into tuberculosis lesions-are likely crucial to the pathogenesis of drug-resistant tuberculosis. These factors have implications for the design of new interventions, drug delivery and dosing mechanisms, and public health policy. We discuss epidemiology and transmission dynamics, including new insights into the fundamental biology of transmission, and we review the utility of newer diagnostic tools, including molecular tests and next-generation whole-genome sequencing, and their potential for clinical effectiveness. Relevant research priorities are highlighted, including optimal medical and surgical management, the role of newer and repurposed drugs (including bedaquiline, delamanid, and linezolid), pharmacokinetic and pharmacodynamic considerations, preventive strategies (such as prophylaxis in MDR and XDR contacts), palliative and patient-orientated care aspects, and medicolegal and ethical issues.

Tuberculosis and the Heart

Owing to the high prevalence of tuberculosis (TB) and human immunodeficiency virus/AIDS, tuberculous heart disease remains an important problem in TB endemic areas. In this review, we reiterate salient aspects of the traditional understanding and approach to its management, and provide important updates on the pathophysiology, diagnosis, and treatment garnered over the past decade of focused clinical and basic science research. We emphasize that, if implemented widely, these improved evidence-based approaches to the disease can build on the early progress made in treating tuberculous heart disease and help further the goal of significantly reducing its historically high morbidity and mortality.

Tuberculous Pericarditis is Multibacillary and Bacterial Burden Drives High Mortality

BACKGROUND

Tuberculous pericarditis is considered to be a paucibacillary process; the large pericardial fluid accumulation is attributed to an inflammatory response to tuberculoproteins. Mortality rates are high. We investigated the role of clinical and microbial factors predictive of tuberculous pericarditis mortality using the artificial intelligence algorithm termed classification and regression tree (CART) analysis.

METHODS

Patients were prospectively enrolled and followed in the Investigation of the Management of Pericarditis (IMPI) registry. Clinical and laboratory data of 70 patients with confirmed tuberculous pericarditis, including time-to-positive (TTP) cultures from pericardial fluid, were extracted and analyzed for mortality outcomes using CART. TTP was translated to log10 colony forming units (CFUs) per mL, and compared to that obtained from sputum in some of our patients.

FINDINGS

Seventy patients with proven tuberculous pericarditis were enrolled. The median patient age was 35 (range: 20-71) years. The median, follow up was for 11.97 (range: 0·03-74.73) months. The median TTP for pericardial fluid cultures was 22 (range: 4-58) days or 3.91(range: 0·5-8·96) log10CFU/mL, which overlapped with the range of 3.24-7.42 log10CFU/mL encountered in sputum, a multi-bacillary disease. The overall mortality rate was 1.43 per 100 person-months. CART identified follow-up duration of 5·23 months on directly observed therapy, a CD4 + count of ≤ 199.5/mL, and TTP ≤ 14 days (bacillary load ≥ 5.53 log10 CFU/mL) as predictive of mortality. TTP interacted with follow-up duration in a non-linear fashion.

INTERPRETATION

Patients with culture confirmed tuberculous pericarditis have a high bacillary burden, and this bacterial burden drives mortality. Thus proven tuberculosis pericarditis is not a paucibacillary disease. Moreover, the severe immunosuppression suggests limited inflammation. There is a need for the design of a highly bactericidal regimen for this condition.