Rationale and design of the Investigation of the Management of Pericarditis (IMPI) trial: a 2 × 2 factorial randomized double-blind multicenter trial of adjunctive prednisolone and Mycobacterium w immunotherapy in tuberculous pericarditis

Joint modeling of longitudinal CD4 count data and time to first occurrence of composite outcome

In this study, we jointly modeled longitudinal CD4 count data and survival outcome (time-to-first occurrence of composite outcome of death, cardiac tamponade or constriction) in other to investigate the effects of Mycobacterium indicus pranii immunotherapy and the CD4 count measurements on the hazard of the composite outcome among patients with HIV and tuberculous (TB) pericarditis. In this joint modeling framework, the models for longitudinal and the survival data are linked by an association structure. The association structure represents the hazard of the event for 1-unit increase in the longitudinal measurement. Models fitting and parameter estimation were carried out using R version 4.2.3. The association structure that represents the strength of the association between the hazard for an event at time point j and the area under the longitudinal trajectory up to the same time j provides the best fit. We found that 1-unit increase in CD4 count results in 2 % significant reduction in the hazard of the composite outcome. Among HIV and TB pericarditis individuals, the hazard of the composite outcome does not differ between of M.indicus pranii versus placebo. Application of joint models to investigate the effect of M.indicus pranii on the hazard of the composite outcome is limited. Hence, this study provides information on the effect of M.indicus pranii on the hazard of the composite outcome among HIV and TB pericarditis patients.

Assessing the hazard of death, cardiac tamponade, and pericardial constriction among HIV and tuberculosis pericarditis patients using the extended Cox-hazard model: Intervention study

Background and Aims

Tuberculous (TB) pericarditis (TBP), a TB of the heart, is linked to significant morbidity and mortality rates. Administering glucocorticoid therapy to individuals with TBP might enhance overall results and lower the likelihood of fatality. However, the actual clinical effectiveness of supplementary glucocorticoids remains uncertain. This study specifically evaluated the effects of prednisolone, prednisolone-antiretroviral therapy (ART) interaction, and other potential risk factors in reducing the hazard of the composite outcome, death, cardiac tamponade, and constriction, among TBP and human immunodeficiency virus (HIV) patients.

Methods

The data used in this study were obtained from the investigation of the Management of Pericarditis trial, a multicentre international randomized double-blind placebo-controlled 2 × 2 factorial study that investigated the effects of two TB treatments, prednisolone and Mycobacterium indicus pranii  immunotherapy in patients with TBP in Africa. This study used a sample size of 587 TBP and HIV-positive patients randomized into prednisolone and its corresponding placebo arm. We used the extended Cox-proportional hazard model to evaluate the effects of the covariates on the hazard of the survival outcomes. Models fitting and parameter estimation were carried out using R version 4.3.1.

Results

Prednisolone reduces the hazard of composite outcome (hazrad ratio [HR] = 0.32, 95% confidence interval [CI] = 0.19 , 0.54 , p < 0.001), cardiac tamponade (HR = 0.14, 95% CI = 0.05, 0.42, p < 0.001) and constriction (HR = 0.81, 95% CI = 0.41, 1.61, p = 0.55). However, prednisolone increases the hazard of death (HR = 1.58, 95% CI = 1.11, 2.24, p = 0.01). Consistent usage of ART reduces the hazard of composite outcome, death, and constriction but insignificantly increased the hazard of cardiac tamponade.

Conclusion

The study offers valuable insights into how prednisolone impact the hazard of different outcomes in patients with TBP and HIV. The findings hold potential clinical significance, particularly in guiding treatment decisions and devising strategies to enhance outcomes in this specific patient group. However, there are concerns about prednisolone potentially increasing the risk of death due to HIV-related death.

A 15-year-old girl with pericardial tuberculosis complicated by cardiac tamponade: A case report in Somalia

Introduction and importance

Pericarditis is a common illness that can appear in a variety of clinical settings and has numerous causes. In developing nations where tuberculosis is still a serious public health issue, more than 50% of cases of pericarditis are related to tuberculosis.

Case presentation

There was no history of TB, alcoholism, IV drug abuse, immunosuppressant, or corticosteroid use. On examination, she had a fever, tachycardia, pulsus paradoxus of 10 mmHg, hypotension, tachypnea, and a distended jugular vein. On auscultation, her heartbeats were muffled, and accompanied by a pericardial rub. Laboratory investigation showed low hematocrit and a high WBC count with lymphocyte predominance. ESR and CRP levels were elevated. Her chest X-ray revealed an enlargement of the cardiac silhouette. The ECG showed low voltage complexes. Echocardiography showed circumferential 30 mm × 25 mm pericardial effusion with fibrin strands in the visceral pericardium. An emergency pericardiocentesis was performed under the guidance of transthoracic echocardiography using sub-xiphoidal standards. Microbiologic analysis of the pericardial fluid confirmed tuberculosis. After successful pericardiocenthesis, the patient's condition improved massively. After three days of pericardiocentasis drainage, TB treatment was started and she was discharged for outpatient flow up.

Clinical discussion

Tuberculous pericarditis is a serious tuberculosis (TB) complication that can be difficult to diagnose and often goes undetected, leading to late complications such as constrictive pericarditis and cardiac tamponade, which lead to increased mortality. This current case illustrates a young female patient presenting with isolated TB pericarditis complicated by cardiac tamponade. She had massive improvement following pericardiocentesis and anti-TB treatment.

Conclusion

In Africa, tuberculous pericarditis should be considered as a differential diagnosis in any patient presenting with moderate to massive pericardial effusion. A high index of suspicion is required for the diagnosis of extrapulmonary TB pericarditis, especially in patients without known risk factors.

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A previously healthy young female patient was admitted with isolated tuberculosis pericarditis complicated by cardiac temponade.

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Transthoracic echocardiography revealed extensive pericardial effusion causing cardiac temponade. Microbiologic analysis of the pericardial fluid confirmed tuberculosis.

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She had massive improvement after she was successfully managed with pericardiocenthesis and anti-TB medication.

Tuberculous Pericarditis—Own Experiences and Recent Recommendations

Tuberculous pericarditis (TBP) accounts for 1% of all forms of tuberculosis and for 1–2% of extrapulmonary tuberculosis. In endemic regions, TBP accounts for 50–90% of effusive pericarditis; in non-endemic, it only accounts for 4%. In the absence of prompt and effective treatment, TBP can lead to very serious sequelae, such as cardiac tamponade, constrictive pericarditis, and death. Early diagnosis of TBP is a cornerstone of effective treatment. The present article summarises the authors’ own experiences and highlights the current status of knowledge concerning the diagnostic and therapeutic algorithm of TBP. Special attention is drawn to new, emerging molecular methods used for confirmation of M. tuberculosis infection as a cause of pericarditis.

A case report of tuberculous constrictive pericarditis necessitating total pericardiectomy

Background

Constrictive pericarditis (CP) is one of the most serious sequelae of tuberculous pericarditis, which is characterized by heart constriction secondary to intense pericardial inflammation and thickening. Several invasive and non-invasive diagnostic modalities are crucial to address the challenges of confirming the diagnosis of CP and to expedite timely intervention.

Case summary

This study reports the case of a Bahraini male with tuberculous lymphadenitis diagnosed with CP as a result of various evaluations. The patient underwent urgent total pericardiectomy and showed remarkable recovery with complete resolution of heart failure symptoms.

Discussion

This case demonstrates the paramount importance of early diagnosis and treatment for patients with CP. In this unique case, the acoustic windows on echocardiography were suboptimal because of pericardial thickening. Further, computed tomography did not show significant calcification of the thickened pericardium. A novel approach of assessing haemodynamics through the right antecubital vein and right radial artery facilitated the accurate diagnosis of CP with confidence. Thereafter, successful pericardiectomy revealed a markedly thickened and stiff pericardium with many abscesses and dense adhesions encasing the heart, and pericardial biopsy showed large caseating granulomas. This case exemplifies the difficulty in diagnosing CP and the favourable outcomes achieved with well-timed surgical intervention.

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.

Outcomes of Stevens-Johnson syndrome and toxic epidermal necrolysis in HIV-infected patients when using systemic steroids and/or intravenous immunoglobulins in Pietermaritzburg, South Africa

Background

Stevens–Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN) are severe life-threatening mucocutaneous reactions. There is an ongoing controversy regarding the use of systemic corticosteroids and intravenous immunoglobulin (IVIG) in SJS/TEN and their utility in HIV-infected patients.

Objectives

The objective was to assess the outcome of a combination of intensive supportive care with oral corticosteroids in SJS and a combination of systemic steroids and IVIG for 3 consecutive days in HIV-infected patients with TEN. In addition, we assessed management in a general dermatology ward without implementing wound debridement.

Methods

This was a retrospective cohort study of 36 HIV-infected adults with SJS/TEN admitted to a tertiary dermatology unit between 1st January 2010 and 31st July 2011. Standard-of-care protocols included identification and elimination of the possible causative drug, meticulous wound care without debridement, initiation of oral prednisone (1 mg/kg/day) on admission for 3 consecutive days, and the addition of IVIG (1 g/kg/day) for 3 consecutive days to those with TEN.

Results

Of the 36 patients in the study, 32 were female. Nevirapine was the commonest drug implicated. A diagnosis of tuberculosis did not increase the case fatality rate. Complications included infections, anaemia, drug-induced hepatitis, ocular involvement, renal impairment, deep vein thrombosis, respiratory distress, Leucopenia, gastritis and hypernatremia. The overall survival rate was 97%.

Conclusion

HIV-infected SJS and TEN patients were treated in a tertiary dermatology ward with a treatment plan of skin care, and a combination of systemic corticosteroids and IVIG respectively had a survival rate of 97%.

Sensitivity analysis for the generalized shared-parameter model framework

In this paper, we assess the effect of tuberculosis pericarditis treatment (prednisolone) on CD4 count changes over time and draw inferences in the presence of missing data. We accounted for the missing data and performed sensitivity analyses to assess robustness of inferences, from a model that assumes that the data are missing at random, to models that assume that the data are not missing at random. Our sensitivity approaches are within the shared-parameter model framework. We implemented the approach by Creemers and colleagues to the CD4 count data and performed simulation studies to evaluate the performance of this approach. We also assessed the influence of potentially influential subjects, on parameter estimates, via the global influence approach. Our results revealed that inferences from missing at random analysis model are robust to not missing at random models and influential subjects did not overturn the study conclusions about prednisolone effect and missing data mechanism. Prednisolone was found to have no significant effect on CD4 count changes over time and also did not interact with anti-retroviral therapy. The simulation studies produced unbiased estimates of prednisolone effect with lower mean square errors and coverage probabilities approximately equal the nominal coverage probability.

An application of a pattern-mixture model with multiple imputation for the analysis of longitudinal trials with protocol deviations

BACKGROUND

The benefit of a given treatment can be evaluated via a randomized clinical trial design. However, protocol deviations may severely compromise treatment effect since such deviations often lead to missing values. The assumption that methods of analysis can account for the missing data cannot be justified and hence methods of analysis based on plausible assumptions should be used. An alternative analysis to the simple imputation methods requires unverifiable assumptions about the missing data. Therefore sensitivity analysis should be performed to investigate the robustness of statistical inferences to alternative assumptions about the missing data.

AIMS

In this paper, we investigate the effect of tuberculosis pericarditis treatment (prednisolone) on CD4 count changes over time and draw inferences in the presence of missing data. The data come from a multicentre clinical trial (the IMPI trial).

METHODS

We investigate the effect of prednisolone on CD4 count changes by adjusting for baseline and time-dependent covariates in the fitted model. To draw inferences in the presence of missing data, we investigate sensitivity of statistical inferences to missing data assumptions using the pattern-mixture model with multiple imputation (PM-MI) approach. We also performed simulation experiment to evaluate the performance of the imputation approaches.

RESULTS

Our results showed that the prednisolone treatment has no significant effect on CD4 count changes over time and that the prednisolone treatment does not interact with time and anti-retroviral therapy (ART). Also, patients' CD4 count levels significantly increase over the study period and patients on ART treatment have higher CD4 count levels compared with those not on ART. The results also showed that older patients had lower CD4 count levels compared with younger patients, and parameter estimates under the MAR assumption are robust to NMAR assumptions.

CONCLUSIONS

Since the parameter estimates under the MAR analysis are robust to NMAR analyses, the process that generated the missing data in the CD4 count measurements is missing at random (MAR). The implication is that valid inferences can be obtained using either the likelihood-based methods or multiple imputation approaches.

Corticosteroids as an adjunct to tuberculosis therapy

INTRODUCTION

Inflammation, or the prolonged resolution of inflammation, contributes to death from tuberculosis. Interest in inflammatory mechanisms and the prospect of beneficial immune modulation as an adjunct to antibacterial therapy has revived and the concept of host directed therapies has been advanced. Such renewed attention has however, overlooked the experience of such therapy with corticosteroids. Areas covered: The authors conducted literature searches and evaluated randomized clinical trials, systematic reviews and current guidelines and summarize these findings. They found evidence of benefit in meningeal and pericardial tuberculosis in HIV-1 uninfected persons, but less so in those HIV-1 coinfected and evidence of harm in the form of opportunist malignancy in those not prescribed antiretroviral therapy. Adjunctive corticosteroids are however of benefit in the treatment and prevention of paradoxical HIV-tuberculosis immune reconstitution inflammatory syndrome. Expert commentary: Further high-quality clinical trials and experimental medicine studies are warranted and analysis of materials arising from such studies could illuminate ways to improve corticosteroid efficacy or identify novel pathways for more specific intervention.

Vaccines for Leprosy and Tuberculosis: Opportunities for Shared Research, Development, and Application

Tuberculosis (TB) and leprosy still represent significant public health challenges, especially in low- and lower middle-income countries. Both poverty-related mycobacterial diseases require better tools to improve disease control. For leprosy, there has been an increased emphasis on developing tools for improved detection of infection and early diagnosis of disease. For TB, there has been a similar emphasis on such diagnostic tests, while increased research efforts have also focused on the development of new vaccines. Bacille Calmette–Guérin (BCG), the only available TB vaccine, provides insufficient and inconsistent protection to pulmonary TB in adults. The impact of BCG on leprosy, however, is significant, and the introduction of new TB vaccines that might replace BCG could, therefore, have serious impact also on leprosy. Given the similarities in antigenic makeup between the pathogens Mycobacterium tuberculosis (Mtb) and M. leprae, it is well possible, however, that new TB vaccines could cross-protect against leprosy. New TB subunit vaccines currently evaluated in human phase I and II studies indeed often contain antigens with homologs in M. leprae. In this review, we discuss pre-clinical studies and clinical trials of subunit or whole mycobacterial vaccines for TB and leprosy and reflect on the development of vaccines that could provide protection against both diseases. Furthermore, we provide the first preclinical evidence of such cross-protection by Mtb antigen 85B (Ag85B)-early secretory antigenic target (ESAT6) fusion recombinant proteins in in vivo mouse models of Mtb and M. leprae infection. We propose that preclinical integration and harmonization of TB and leprosy research should be considered and included in global strategies with respect to cross-protective vaccine research and development.

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.

Patterns of international collaboration in cardiovascular research in sub-Saharan Africa

The rising prevalence of cardiovascular disease in sub-Saharan Africa (SSA) constitutes a significant health and socio-economic challenge for the countries in the region. This study examines the patterns and scientific impact of international collaboration in cardiovascular research (CVR) in SSA. Bibliographic data from 2005 to 2014 were obtained from the Web of Science for cardiovascular-related publications with at least one author affiliated to an SSA country. The number of publications involving multiple SSA countries over this period accounted for less than 10% of the total number of multi-country publications that included at least one SSA country. Collaboration patterns reflected dominance by countries in Europe and North America, with South Africa accounting for the bulk of scientific collaboration in CVR within SSA. The findings indicate that pro-active strategies are needed to strengthen collaboration in CVR across SSA for the region to derive health and socio-economic benefits from locally conducted research.

Exploring unknowns in cardiology

To mark the 10th anniversary of Nature Reviews Cardiology in November 2014, five of our Advisory Board members were invited to consider a topic within cardiology about which we know too little. A diverse range of subjects are highlighted in this Perspectives article, including preoperative assessment of right ventricular function, the burden of cardiomyopathies in Africa, the measurement of fractional flow reserve to guide coronary intervention, the interaction between genes and environment in cardiovascular disease, and the difficulty of predicting atherosclerotic plaque rupture. The five key opinion leaders from around the globe also suggest ways in which future research could be targeted to address the deficits in our understanding, with the aim of preventing cardiovascular disease, improving patient care, and reducing morbidity and mortality.

Prednisolone and Mycobacterium indicus pranii in tuberculous pericarditis

BACKGROUND

Tuberculous pericarditis is associated with high morbidity and mortality even if antituberculosis therapy is administered. We evaluated the effects of adjunctive glucocorticoid therapy and Mycobacterium indicus pranii immunotherapy in patients with tuberculous pericarditis.

METHODS

Using a 2-by-2 factorial design, we randomly assigned 1400 adults with definite or probable tuberculous pericarditis to either prednisolone or placebo for 6 weeks and to either M. indicus pranii or placebo, administered in five injections over the course of 3 months. Two thirds of the participants had concomitant human immunodeficiency virus (HIV) infection. The primary efficacy outcome was a composite of death, cardiac tamponade requiring pericardiocentesis, or constrictive pericarditis.

RESULTS

There was no significant difference in the primary outcome between patients who received prednisolone and those who received placebo (23.8% and 24.5%, respectively; hazard ratio, 0.95; 95% confidence interval [CI], 0.77 to 1.18; P=0.66) or between those who received M. indicus pranii immunotherapy and those who received placebo (25.0% and 24.3%, respectively; hazard ratio, 1.03; 95% CI, 0.82 to 1.29; P=0.81). Prednisolone therapy, as compared with placebo, was associated with significant reductions in the incidence of constrictive pericarditis (4.4% vs. 7.8%; hazard ratio, 0.56; 95% CI, 0.36 to 0.87; P=0.009) and hospitalization (20.7% vs. 25.2%; hazard ratio, 0.79; 95% CI, 0.63 to 0.99; P=0.04). Both prednisolone and M. indicus pranii, each as compared with placebo, were associated with a significant increase in the incidence of cancer (1.8% vs. 0.6%; hazard ratio, 3.27; 95% CI, 1.07 to 10.03; P=0.03, and 1.8% vs. 0.5%; hazard ratio, 3.69; 95% CI, 1.03 to 13.24; P=0.03, respectively), owing mainly to an increase in HIV-associated cancer.

CONCLUSIONS

In patients with tuberculous pericarditis, neither prednisolone nor M. indicus pranii had a significant effect on the composite of death, cardiac tamponade requiring pericardiocentesis, or constrictive pericarditis. (Funded by the Canadian Institutes of Health Research and others; IMPI ClinicalTrials.gov number, NCT00810849.).

Management of pericarditis and myocarditis: could heart-rate-reducing drugs hold a promise?

Rest is usually recommended in acute pericarditis and acute myocarditis. Given that myocarditis often leads to hospitalization, this task seems easy to carry out in hospital practice; however, it could be a real challenge at home in daily life. Heart rate-lowering treatments (mainly beta-blockers) are usually recommended in case of acute myocarditis, especially in case of heart failure or arrhythmias, but level of proof remains weak. Calcium channel inhibitors and digoxin are sometimes proposed, albeit in limited situations. It is possible that rest or even heart rate-lowering treatments could help to manage these patients by preventing heart failure as well as by limiting "mechanical inflammation" and controlling arrhythmias, especially life-threatening ones. Whether heart rate has an effect on inflammation remains unclear. Several questions remain unsolved, such as the duration of such treatments, especially in light of new heart rate-lowering treatments, such as ivabradine. In this review, we discuss rest and heart-rate lowering medications for the treatment of pericarditis and myocarditis. We also highlight some work in experimental models that indicates the beneficial effects of such treatments for these conditions. Finally, we suggest certain experimental avenues, through the use of animal models and clinical studies, which could lead to improved management of these patients.

Mycobacterium marinum: a potential immunotherapy for Mycobacterium tuberculosis infection

Purpose

The aim of the present study was to investigate the immune response induced by Mycobacterium marinum infection in vitro and the potential of M. marinum as an immunotherapy for M. tuberculosis infection.

Methods

The potential human immune response to certain bacillus infections was investigated in an immune cell-bacillus coculture system in vitro. As a potential novel immunotherapy, M. marinum was studied and compared with two other bacilli, Bacillus Calmette-Guérin (BCG) and live attenuated M. tuberculosis. We examined the changes in both the bacilli and immune cells, especially the time course of the viability of mycobacteria in the coculture system and host immune responses including multinuclear giant cell formation by Wright-Giemsa modified staining, macrophage polarization by cell surface antigen expression, and cytokines/chemokine production by both mRNA expression and protein secretion.

Results

The M. marinum stimulated coculture group showed more expression of CD209, CD68, CD80, and CD86 than the BCG and M. tuberculosis (an attenuated strain, H37Ra) groups, although the differences were not statistically significant. Moreover, the M. marinum group expressed more interleukin (IL)-1B and IL-12p40 on day 3 (IL-1B: P = 0.003 and 0.004, respectively; IL-12p40: P = 0.001 and 0.011, respectively), a higher level of CXCL10 on day 1 (P = 0.006 and 0.026, respectively), and higher levels of chemokine (C-X-C motif) ligand (CXCL) 8 and chemokine (C motif) ligand (XCL) 1 on day 3 (CXCL8: P = 0.012 and 0.014, respectively; XCL1: P = 0.000 and 0.000, respectively). The M. marinum stimulated coculture group also secreted more tumor necrosis factor (TNF)-α, IL-1β, and IL-10 on day 1 (TNF-α: P = 0.000 and 0.000, respectively; IL-1β: P = 0.000 and 0.000, respectively; IL-10: P = 0.002 and 0.019, respectively) and day 3 (TNF-α: P = 0.000 and 0.000, respectively; IL-1β: P = 0.000 and 0.001, respectively; IL-10: P = 0.000 and 0.000, respectively). In addition, the colony-forming units (an index of viability) of M. marinum in the M. marinum stimulated coculture group was significantly less than that of BCG and H37Ra in their corresponding bacillus stimulated groups (P = 0.037 and 0.013, respectively).

Conclusion

Our results indicated that M. marinum could be a potentially safe and effective immunotherapy.

Recent advances in HIV-associated cardiovascular diseases in Africa

The last decade has witnessed major advances in our understanding of the epidemiology and pathophysiology of HIV-related cardiovascular disease in sub-Saharan Africa. In this review, we summarise these and discuss clinically relevant advances in diagnosis and treatment. In the Heart of Soweto Study, 10% of patients with newly diagnosed cardiovascular disease were HIV positive, and the most common HIV-related presentations were cardiomyopathy (38%), pericardial disease (13%) and pulmonary arterial hypertension (8%). HIV-related cardiomyopathy is more common with increased immunosuppression and HIV viraemia. With adequate antiretroviral therapy, the prevalence is low. Contributing factors such as malnutrition and genetic predisposition are under investigation. In other settings, pericardial disease is the most common presentation of HIV-related cardiovascular disease (over 40%), and over 90% of pericardial effusions are due to Mycobacterium tuberculosis (TB) pericarditis. HIV-associated TB pericarditis is associated with a greater prevalence of myopericarditis, a lower rate of progression to constriction, and markedly increased mortality. The role of steroids is currently under investigation in the form of a randomised controlled trial. HIV-associated pulmonary hypertension is significantly more common in sub-Saharan Africa than in developed countries, possibly as a result of interactions between HIV and other infectious agents, with very limited treatment options. It has recently been recognised that patients with HIV are at increased risk of sudden death. Infection with HIV is independently associated with QT prolongation, which is more marked with hepatitis C co-infection and associated with a 4.5-fold higher than expected rate of sudden death. The contribution of coronary disease to the overall burden of HIV-associated cardiovascular disease is still low in sub-Saharan Africa.

Heart failure in sub-Saharan Africa

The heart failure syndrome has been recognized as a significant contributor to cardiovascular disease burden in sub-Saharan African for many decades. Seminal knowledge regarding heart failure in the region came from case reports and case series of the early 20th century which identified infectious, nutritional and idiopathic causes as the most common. With increasing urbanization, changes in lifestyle habits, and ageing of the population, the spectrum of causes of HF has also expanded resulting in a significant burden of both communicable and non-communicable etiologies. Heart failure in sub-Saharan Africa is notable for the range of etiologies that concurrently exist as well as the healthcare environment marked by limited resources, weak national healthcare systems and a paucity of national level data on disease trends. With the recent publication of the first and largest multinational prospective registry of acute heart failure in sub-Saharan Africa, it is timely to review the state of knowledge to date and describe the myriad forms of heart failure in the region. This review discusses several forms of heart failure that are common in sub-Saharan Africa (e.g., rheumatic heart disease, hypertensive heart disease, pericardial disease, various dilated cardiomyopathies, HIV cardiomyopathy, hypertrophic cardiomyopathy, endomyocardial fibrosis, ischemic heart disease, cor pulmonale) and presents each form with regard to epidemiology, natural history, clinical characteristics, diagnostic considerations and therapies. Areas and approaches to fill the remaining gaps in knowledge are also offered herein highlighting the need for research that is driven by regional disease burden and needs.