Corticosteroids in tuberculosis

Use of standardised patients to assess tuberculosis case management by private pharmacies in Patna, India: A repeat cross-sectional study

As the first point of care for many healthcare seekers, private pharmacies play an important role in tuberculosis (TB) care. However, previous studies in India have showed that private pharmacies commonly dispense symptomatic treatments and broad-spectrum antibiotics over-the-counter (OTC), rather than referring patients for TB testing. Such inappropriate management by pharmacies can delaye TB diagnosis. We assessed medical advice and OTC drug dispensing practices of pharmacists for standardized patients presenting with classic symptoms of pulmonary TB (case 1) and for those with sputum smear positive pulmonary TB (case 2), and examined how practices have changed over time in an urban Indian site. We examined how and whether private pharmacies improved practices for TB in 2019 compared to a baseline study conducted in 2015 in the city of Patna, using the same survey sampling techniques and study staff. The proportion of patient-pharmacist interactions that resulted in correct or ideal management, as well as the proportion of interactions resulting in antibiotic, quinolone, and corticosteroid are presented, with standard errors clustered at the provider level. To assess the difference in case management and the use of drugs across the two cases by round, a difference in difference (DiD) model was employed. A total of 936 SP interactions were completed over both rounds of survey. Our results indicate that across both rounds of data collection, 331 of 936 (35%; 95% CI: 32-38%) of interactions were correctly managed. At baseline, 215 of 500 (43%; 95% CI: 39-47%) of interactions were correctly managed whereas 116 of 436 (27%; 95% CI: 23-31%) were correctly managed in the second round of data collection. Ideal management, where in addition to a referral, patients were not prescribed any potentially harmful medications, was seen in 275 of 936 (29%; 95% CI: 27-32%) of interactions overall, with 194 of 500 (39%; 95% CI: 35-43%) of interactions at baseline and 81 of 436 (19%; 95% CI: 15-22%) in round 2. No private pharmacy dispensed anti-TB medications without a prescription. On average, the difference in correct case management between case 1 vs. case 2 dropped by 20 percent points from baseline to the second round of data collection. Similarly, ideal case management decreased by 26 percentage points between rounds. This is in contrast with the dispensation of medicines, which had the opposite effect between rounds; the difference in dispensation of quinolones between case 1 and case 2 increased by 14 percentage points, as did corticosteroids by 9 percentage points, antibiotics by 25 percentage points and medicines generally by 30 percentage points. Our standardised patient study provides valuable insights into how private pharmacies in an Indian city changed their management of patients with TB symptoms or with confirmed TB over a 5-year period. We saw that overall, private pharmacy performance has weakened over time. However, no OTC dispensation of anti-TB medications occurred in either survey round. As the first point of contact for many care seekers, continued and sustained efforts to engage with Indian private pharmacies should be prioritized.

The Risk of Sarcoidosis Misdiagnosis and the Harmful Effect of Corticosteroids When the Disease Picture Is Incomplete

Sarcoidosis is a complex granulomatous disease of unknown etiology. Due to the heterogeneity of the disease, the diagnosis remains challenging in many cases, often at the physician's discretion, requiring a thorough and complex investigation. Many other granulomatous diseases have the potential to mimic sarcoidosis, whether infectious, occupational, or autoimmune diseases and starting an unnecessary corticosteroid treatment can worsen the patient's prognosis, leading to side effects that can be harder to treat than the actual disease.

Review of the Effectiveness of Various Adjuvant Therapies in Treating Mycobacterium tuberculosis

Tuberculosis disease is caused by the bacterium Mycobacterium tuberculosis. It is estimated that 10 million people have developed tuberculosis disease globally, leading to 1.4 million deaths in 2019. Treatment of tuberculosis has been especially challenging due to the rise of multidrug-resistant (MDR-TB) and extensive drug-resistant (XDR-TB) tuberculosis. In addition to drug-resistant genotypes, the standard treatment of tuberculosis by first-line agents is also challenging due to toxicity and costs. In the last four decades, there have only been two new anti-tuberculosis agents—bedaquiline and delamanid. Therefore, shorter, safer, and more cost-effective therapies are needed to adequately treat tuberculosis. In this review, we explore various adjuvants such as glutathione, everolimus, vitamin D, steroid, aspirin, statin, and metformin and their usefulness in reducing the burden of tuberculosis. Glutathione, everolimus, aspirin, and metformin showed the most promise in alleviating the burden of tuberculosis. Despite their potential, more clinical trials are needed to unequivocally establish the effectiveness of these adjuvants as future clinical therapies. Methods: The journals for this review were selected by conducting a search via PubMed, Google Scholar, and The Lancet. Our first search included keywords such as “tuberculosis” and “adjuvant therapy.” From the search, we made a list of adjuvants associated with tuberculosis, and this helped guide us with our second online database search. Using the same three online databases, we searched “tuberculosis” and “respective therapy.” The adjuvants included in the paper were selected based on the availability of sufficient research and support between the therapy and tuberculosis. Adjuvants with minimal research support were excluded. There were no specific search criteria regarding the timing of publication, with our citations ranging between 1979 to 2021.

Pathology of TB/COVID-19 Co-Infection: The phantom menace

Tuberculosis (TB) and coronavirus disease 2019 (COVID-19) are currently the two main causes of death among infectious diseases. There is an increasing number of studies trying to elucidate the interactions between Mycobacterium tuberculosis and SARS-CoV-2. Some of the first case reports point to a worsening of respiratory symptoms in co-infected TB/COVID-19 individuals. However, data from the cohort studies has shown some conflicting results. This study proposes to conduct a systematic review on the current literature on TB/COVID-19 co-infection cohorts, evaluating clinical and epidemiological data, focusing on its implications to the immune system. From an immunological perspective, the TB/COVID-19 co-infection has the potential to converge in a "perfect storm". The disorders induced by each pathogen to the immunomodulation tend to induce an unbalanced inflammatory response, which can promote the progression and worsening of both diseases. Understanding the nature of the interactions between M. tuberculosis and SARS-CoV-2 will be crucial for the development of therapeutic strategies against co-infection.

Chemocentric Informatics Analysis: Dexamethasone Versus Combination Therapy for COVID-19

COVID-19 is a biphasic infectious disease with no approved vaccine or pharmacotherapy. The first drug that has shown promise in reducing COVID-19 mortality in severely-ill patients is dexamethasone, a cheap, well-known anti-inflammatory glucocorticoid, approved for the treatment of inflammatory conditions including respiratory diseases such as asthma and tuberculosis. However, about 80% of COVID-19 patients requiring oxygenation, and about 67% of patients on ventilators, are not responsive to dexamethasone therapy mainly. Additionally, using higher doses of dexamethasone for prolonged periods of time can lead to severe side effects and some patients may develop corticosteroid resistance leading to treatment failure. In order to increase the therapeutic efficacy of dexamethasone in COVID-19 patients, while minimizing dexamethasone-related complications that could result from using higher doses of the drug, we applied a chemocentric informatics approach to identify combination therapies. Our results indicated that combining dexamethasone with fast long-acting beta-2 adrenergic agonists (LABAs), such as formoterol and salmeterol, can ease respiratory symptoms hastily, until dexamethasone's anti-inflammatory and immunosuppressant effects kick in. Our studies demonstrated that LABAs and dexamethasone (or other glucocorticoids) exert synergistic effects that will augment both anti-inflammatory and fibronectin-mediated anticoagulant effects. We also propose other alternatives to LABAs that are supported by sound systems biology evidence, such as nitric oxide. Other drugs such as sevoflurane and treprostinil interact with the SARS-CoV-2 interactome and deserve further exploration. Moreover, our chemocentric informatics approach provides systems biology evidence that combination therapies for COVID-19 will have higher chances of perturbing the SARS-CoV-2 human interactome, which may negatively impact COVID-19 disease pathways.

Small Animal Model of Post-chemotherapy Tuberculosis Relapse in the Setting of HIV Co-infection

Tuberculosis relapse following drug treatment of active disease is an important global public health problem due to the poorer clinical outcomes and increased risk of drug resistance development. Concurrent infection with HIV, including in those receiving anti-retroviral therapy (ART), is an important risk factor for relapse and expansion of drug resistant Mycobacterium tuberculosis (Mtb) isolates. A greater understanding of the HIV-associated factors driving TB relapse is important for development of interventions that support immune containment and complement drug therapy. We employed the humanized mouse to develop a new model of post-chemotherapy TB relapse in the setting of HIV infection. Paucibacillary TB infection was observed following treatment with Rifampin and Isoniazid and subsequent infection with HIV-1 was associated with increased Mtb burden in the post-drug phase. Organized granulomas were observed during development of acute TB and appeared to resolve following TB drug therapy. At relapse, granulomatous pathology in the lung was infrequent and mycobacteria were most often observed in the interstitium and at sites of diffuse inflammation. Compared to animals with HIV mono-infection, higher viral replication was observed in the lung and liver, but not in the periphery, of animals with post-drug TB relapse. The results demonstrate a potential role for the humanized mouse as an experimental model of TB relapse in the setting of HIV. Long term, the model could facilitate discovery of disease mechanisms and development of clinical interventions.

Laboratory evaluation of the IFN-γ circuit for the molecular diagnosis of Mendelian susceptibility to mycobacterial disease

The integrity of the interferon (IFN)-γ circuit is necessary to mount an effective immune response to intra-macrophagic pathogens, especially Mycobacteria. Inherited monogenic defects in this circuit that disrupt the production of, or response to, IFN-γ underlie a primary immunodeficiency known as Mendelian susceptibility to mycobacterial disease (MSMD). Otherwise healthy patients display a selective susceptibility to clinical disease caused by poorly virulent mycobacteria such as BCG (bacille Calmette-Guérin) vaccines and environmental mycobacteria, and more rarely by other intra-macrophagic pathogens, particularly Salmonella and M. tuberculosis. There is high genetic and allelic heterogeneity, with 19 genetic etiologies due to mutations in 10 genes that account for only about half of the patients reported. An efficient laboratory diagnostic approach to suspected MSMD patients is important, because it enables the establishment of specific therapeutic measures that will improve the patient's prognosis and quality of life. Moreover, it is essential to offer genetic counseling to affected families. Herein, we review the various genetic and immunological diagnostic approaches that can be used in concert to reach a molecular and cellular diagnosis in patients with MSMD.

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.

Corticosteroids for tuberculous pleurisy

BACKGROUND

Corticosteroids used in addition to antituberculous therapy have been reported to benefit people with tuberculous pleurisy. However, research findings are inconsistent and raise doubt as to whether such treatment is worthwhile. There is also concern regarding the potential adverse effects of corticosteroids, especially in HIV-positive people.

OBJECTIVES

To evaluate the effects of adding corticosteroids to drug regimens for tuberculous pleural effusion.

SEARCH METHODS

In April 2016, we searched the Cochrane Infectious Diseases Group Specialized Register, CENTRAL (the Cochrane Library), MEDLINE, Embase, LILACS, Current Controlled Trials, and the reference lists of articles identified by the literature search.

SELECTION CRITERIA

Randomized controlled trials (RCTs) and quasi-RCTs that compared any corticosteroid with no treatment, placebo, or other active treatment (both groups should have received the same antituberculous drug regimen) in people diagnosed with tuberculous pleurisy.

DATA COLLECTION AND ANALYSIS

Two review authors independently screened the search results, extracted data from the included trials, and assessed trial methodological quality using the Cochrane 'Risk of bias' tool. We analysed the data using risk ratios (RR) with 95% confidence intervals (CIs). We applied the fixed-effect model in the absence of statistically significant heterogeneity.

MAIN RESULTS

Six trials with 590 participants met the inclusion criteria, which were conducted in Asia (three trials), Africa (two trials), and Europe (one trial). Two trials were in HIV-negative people, one trial was in HIV-positive people, and three trials did not report HIV status.Corticosteroids may reduce the time to resolution of pleural effusion. Risk of residual pleural effusion on chest X-ray was reduced by 45% at eight weeks (RR 0.54, 95% CI 0.37 to 0.78; 237 participants, 2 trials, low certainty evidence), and 65% at 24 weeks (RR 0.35, 95% CI 0.18 to 0.66; 237 participants, 2 trials, low certainty evidence).Compared with control, corticosteroids may reduce the risk of having pleural changes (such as pleural thickening or pleural adhesions), on chest X-ray at the end of follow-up by almost one third (RR 0.72, 95% CI 0.57 to 0.92; 393 participants, 5 trials,low certainty evidence), which translates to an absolute risk reduction of 16%.One trial reported deaths in people that were HIV-positive, with no obvious difference between the groups; the trial authors' analysis suggests that the deaths observed in this trial were related to HIV disease rather than pleural TB (RR 0.91, 95% CI 0.64 to 1.31; 197 participants, 1 trial).We found limited data on long-term functional respiratory impairment on 187 people in two trials, which reported that average percentage predicted forced vital capacity was similar in the group receiving prednisolone and in the control group (very low certainty evidence).The risk of adverse events that led to discontinuation of the trial drug was higher in people with pleural TB receiving corticosteroids (RR 2.78, 95% CI 1.11 to 6.94; 587 participants, 6 trials, low certainty evidence). The trial in HIV-positive people reported on six different HIV-related infections, with no obvious differences. However, cases of Kaposi's sarcoma were only seen in the corticosteroid group (with 6/99 cases in the steroid group compared to 0/98 in the control group) (very low certainty evidence).

AUTHORS' CONCLUSIONS

Long-term respiratory function is potentially the most important outcome for assessing the effects of adjunctive treatments for people with pleural TB. However, the information on the impact of pleural TB on long-term respiratory function is unknown and could be eclipsed by other risk factors, such as concurrent pulmonary TB, smoking, and HIV. This probably needs to be quantified to help decide whether further trials of corticosteroids for pleural TB would be worthwhile.

Detection of latent tuberculosis infection among migrant farmworkers along the US-Mexico border

Background

Migrant farmworkers are among the highest-risk populations for latent TB infection (LTBI) in the United States with numerous barriers to healthcare access and increased vulnerability to infectious diseases. LTBI is usually diagnosed on the border using the tuberculin skin test (TST). QuantiFERON-TB Gold In-Tube (QFT-GIT) also measures immune response against specific Mycobacterium tuberculosis antigens. The objective of this study is to assess the comparability of TST and QFT-GIT to detect LTBI among migrant farmworkers on the border, as well as to examine the effects of various demographic and clinical factors on test positivity.

Methods

Participants were recruited using mobile clinics on the San Luis US-Mexico border and tested with QFT-GIT and TST. Demographic profiles and clinical histories were collected. Kappa coefficients assessed agreement between TST and QFT-GIT using various assay cutoffs. Logistic regression examined factors associated with positive TST or QFT-GIT results.

Results

Of 109 participants, 59 of 108 (55 %) were either TST (24/71, 34 %) or QFT-GIT (52/106, 50 %) positive. Concordance between TST and QFT-GIT was fair (71 % agreement, ĸ = 0.38, 95 % CI: 0.15, 0.61). Factors associated with LTBI positivity included smoking (OR = 1.26, 95 % CI–1.01–1.58) and diabetes/high blood sugar (OR = 0.70, 95 % CI = 0.51–0.98).

Discussion

Test concordance between the two tests was fair, with numerous discordant results observed. Greater proportion of positives detected using QFT-GIT may help avoid LTBI under-diagnosis. Assessment of LTBI status on the border provides evidence whether QFT-GIT should replace the TST in routine practice, as well as identifies risk factors for LTBI among migrant populations.

Electronic supplementary material

The online version of this article (doi:10.1186/s12879-016-1959-3) contains supplementary material, which is available to authorized users.

Use of standardised patients to assess antibiotic dispensing for tuberculosis by pharmacies in urban India: a cross-sectional study

BACKGROUND

India's total antibiotic use is the highest of any country. Patients often receive prescription-only drugs directly from pharmacies. Here we aimed to assess the medical advice and drug dispensing practices of pharmacies for standardised patients with presumed and confirmed tuberculosis in India.

METHODS

In this cross-sectional study in the three Indian cities Delhi, Mumbai, and Patna, we developed two standardised patient cases: first, a patient presenting with 2-3 weeks of pulmonary tuberculosis symptoms (Case 1); and second, a patient with microbiologically confirmed pulmonary tuberculosis (Case 2). Standardised patients were scheduled to present each case once to sampled pharmacies. We defined ideal management for both cases a priori as referral to a health-care provider without dispensing antibiotics or steroids or both.

FINDINGS

Between April 1, 2014, and Nov 29, 2015, we sampled 622 pharmacies in Delhi, Mumbai, and Patna. Standardised patients completed 1200 (96%) of 1244 interactions. We recorded ideal management (defined as referrals without the use of antibiotics or steroids) in 80 (13%) of 599 Case 1 interactions (95% CI 11-16) and 372 (62%) of 601 Case 2 interactions (95% CI 58-66). Antibiotic use was significantly lower in Case 2 interactions (98 [16%] of 601, 95% CI 13-19) than in Case 1 (221 [37%] of 599, 95% CI 33-41). First-line anti-tuberculosis drugs were not dispensed in any city. The differences in antibiotic or steroid use and number of medicines dispensed between Case 1 and Case 2 were almost entirely attributable to the difference in referral behaviour.

INTERPRETATION

Only some urban Indian pharmacies correctly managed patients with presumed tuberculosis, but most correctly managed a case of confirmed tuberculosis. No pharmacy dispensed anti-tuberculosis drugs for either case. Absence of a confirmed diagnosis is a key driver of antibiotic misuse and could inform antimicrobial stewardship interventions.

FUNDING

Grand Challenges Canada, Bill & Melinda Gates Foundation, Knowledge for Change Program, and World Bank Development Research Group.

An Uncommon Case of Chronic Tubercular Appendicitis

Tuberculosis (TB) is a common disease that ranks as the second leading cause of death from an infectious disease worldwide, after the human immunodeficiency virus (HIV). However, primary TB of the appendix is rare and may or may not be associated with specific clinical features. Thus, diagnosis is made only after histopathological examination. It suggests that all surgically removed appendices should be subjected to histopathological examination. This reported case is an uncommon case of chronic tubercular appendicitis.

Interferon Gamma-Based Detection of Latent Tuberculosis Infection in the Border States of Nuevo Leon and Tamaulipas, Mexico

Nearly one-third of the world’s population is infected with latent tuberculosis (LTBI). Tuberculosis (TB) rates in the border states are higher than national rates in both the US and Mexico, with the border accounting for 30% of total registered TB cases in both countries. However, LTBI rates in the general population in Mexican border states are unknown. In this region, LTBI is diagnosed using the tuberculin skin test (TST). New methods of detection more specific than TST have been developed, although there is currently no gold standard for LTBI detection. Our objective is to demonstrate utility of the Quantiferon TB gold In-Tube (QFT-GIT) test compared with the TST to detect LTBI among border populations. This is an observational, cross-sectional study carried out in border areas of the states of Nuevo Leon and Tamaulipas, Mexico. Participants (n = 210) provided a TST and blood sample for the QFT-GIT. Kappa coefficients assessed the agreement between TST and QFT-GIT. Participant characteristics were compared using Fisher exact tests. Thirty-eight percent of participants were diagnosed with LTBI by QFT-GIT. The proportion of LTBI detected using QFT-GIT was almost double [38% (79/210)] that found by TST [19% (39/210)] (P < 0.001). Concordance between TST and QFT-GIT was low (kappa = 0.37). We recommend further studies utilizing the QFT-GIT test to detect LTBI among border populations.

Adjunctive steroid therapy for managing pulmonary tuberculosis

BACKGROUND

Tuberculosis causes approximately 8.6 million disease episodes and 1.3 million deaths worldwide per year. Although curable with standardized treatment, outcomes for some forms of tuberculosis are improved with adjunctive corticosteroid therapy. Whether corticosteroid therapy would be beneficial in treating people with pulmonary tuberculosis is unclear.

OBJECTIVES

To evaluate whether adjunctive corticosteroid therapy reduces mortality, accelerates clinical recovery or accelerates microbiological recovery in people with pulmonary tuberculosis.

SEARCH METHODS

We identified studies indexed from 1966 up to May 2014 by searching: Cochrane Infectious Diseases Group's trials register, Cochrane Central Register of Controlled Trials, MEDLINE, EMBASE and LILACS using comparative search terms. We handsearched reference lists of all identified studies and previous reviews and contacted relevant researchers, organizations and companies to identify grey literature.

SELECTION CRITERIA

Randomized controlled trials and quasi-randomized control trials of recognized antimicrobial combination regimens and corticosteroid therapy of any dose or duration compared with either no corticosteroid therapy or placebo in people with pulmonary tuberculosis were included.

DATA COLLECTION AND ANALYSIS

At least two investigators independently assessed trial quality and collected data using pre-specified data extraction forms. Findings were reported as narrative or within tables. If appropriate, Mantel-Haenszel meta-analyses models were used to calculate risk ratios.

MAIN RESULTS

We identified 18 trials, including 3816 participants, that met inclusion criteria. When compared to taking placebo or no steroid, corticosteroid use was not shown to to reduce all-cause mortality, or result in higher sputum conversion at 2 months or at 6 months (mortality: RR 0.77, 95%CI 0.51 to 1.15, 3815 participants, 18 studies, low quality evidence; sputum conversion at 2 months RR 1.03, 95%CI 0.97 to 1.09, 2750 participants, 12 studies; at 6 months; RR1.01, 95%CI 1.01, 95%CI 0.98 to 1.04, 2150 participants, 9 studies, both low quality evidence). However, corticosteroid use was found to increase weight gain (data not pooled, eight trials, 1203 participants, low quality evidence), decrease length of hospital stay (data not pooled, three trials, participants 379, very low quality of evidence) and increase clinical improvement within one month (RR 1.16, 95% CI 1.09 to 1.24; five trials, 497 participants, low quality evidence).

AUTHORS' CONCLUSIONS

It is unlikely that adjunctive corticosteroid treatment provides major benefits for people with pulmonary tuberculosis. Short term clinical benefits found did not appear to be maintained in the long term. However, evidence available to date is of low quality. In order to evaluate whether adjunctive corticosteroids reduce mortality, or accelerate clinical or microbiological recovery in people with pulmonary tuberculosis further large randomized control trials sufficiently powered to detect changes in such outcomes are needed.

The current state of tuberculosis vaccines

Tuberculosis continues to persist despite widespread use of BCG, the only licensed vaccine to prevent TB. BCG's limited efficacy coupled with the emergence of drug-resistant strains of Mycobacterium tuberculosis emphasizes the need for a more effective vaccine for combatting this disease. However, the development of a TB vaccine is hindered by the lack of immune correlates, suboptimal animal models, and limited funding. An adolescent/adult vaccine would have the greatest public health impact, but effective delivery of such a vaccine will require a better understanding of global TB epidemiology, improved infrastructure, and engagement of public health leaders and global manufacturers. Here we discuss the current state of tuberculosis vaccine research and development, including our understanding of the underlying immunology as well as the challenges and opportunities that may hinder or facilitate the development of a new and efficacious vaccine.

Corticosteroids for prevention of mortality in people with tuberculosis: a systematic review and meta-analysis

BACKGROUND

The effects of corticosteroids are systemic, but their benefits in tuberculosis are thought to be organ specific, with clinicians using them routinely to treat some forms of tuberculosis (such as meningitis), but not others. We aimed to assess the effects of steroids on mortality attributable to all forms of tuberculosis across organ systems.

METHODS

We did a systematic review and meta-analysis to estimate the efficacy of steroids for the prevention of mortality in all forms of tuberculosis, and to quantify heterogeneity in this outcome between affected organ systems. We searched the Cochrane Infectious Diseases Group trials register, the Cochrane Central Register of Controlled Trials, Medline, Embase, and Literatura Latino-Americana e do Caribe em Ciências da Saúde (LILACS) for studies published up to Sept 6, 2012, and checked reference lists of included studies and relevant reviews. We included all trials in people with tuberculosis in any organ system, with tuberculosis defined clinically or microbiologically. There were no restrictions by age, comorbidity, publication language, or type, dose, or duration of steroid treatment. We used the Mantel-Haenszel method to summarise mortality across trials.

FINDINGS

We identified 41 eligible trials, 18 of which assessed pulmonary tuberculosis. 20 of the 41 trials (including 13 of those for pulmonary tuberculosis) were done before the introduction of modern rifampicin-containing antituberculosis chemotherapy. Meta-analysis stratified by affected organ systems identified no heterogeneity; steroids reduced mortality by 17% (risk ratio [RR] 0·83, 95% CI 0·74-0·92; I(2) 0%), consistent across all organ groups. In a sensitivity analysis that only included trials that used rifampicin-containing regimens, the results were similar (RR 0·85, 95% CI 0·74-0·98; I(2) 21%). A sensitivity analysis in pulmonary tuberculosis that excluded trials with high potential risks of bias suggested a slight benefit, but the point estimate was closer to no effect and the difference was not significant (RR 0·93, 95% CI 0·60-1·44).

INTERPRETATION

Steroids could be effective in reducing mortality for all forms of tuberculosis, including pulmonary tuberculosis. However, further evidence is needed since few recent trials have assessed the effectiveness of corticosteroids in patients with pulmonary tuberculosis.

FUNDING

UK Department for International Development.

Cost-effectiveness of latent tuberculosis screening before steroid therapy for idiopathic nephrotic syndrome in children

BACKGROUND

Guidelines differ on screening recommendations for latent tuberculosis infection (LTBI) prior to immunosuppressive therapy. We aimed to determine the most cost-effective LTBI screening strategy before long-term steroid therapy in a child with new-onset idiopathic nephrotic syndrome.

STUDY DESIGN

Markov state-transition model.

SETTING & POPULATION

5-year-old boy with new-onset idiopathic nephrotic syndrome.

MODEL, PERSPECTIVE, & TIMEFRAME

The Markov model took a societal perspective over a lifetime horizon.

INTERVENTION

3 strategies were compared: universal tuberculin skin testing (TST), targeted screening using a risk-factor questionnaire, and no screening. A secondary model included the newer interferon γ release assays (IGRAs), requiring only one visit and having greater specificity than TST.

OUTCOMES

Marginal cost-effectiveness ratios (2010 US dollars) with effectiveness measured as quality-adjusted life-years (QALYs).

RESULTS

At an LTBI prevalence of 1.1% (the average US childhood prevalence in our base case), a no-screening strategy dominated ($2,201; 29.3356 QALYs) targeted screening ($2,218; 29.3356 QALYs) and universal TST ($2,481; 29.3347 QALYs). At a prevalence >10.3%, targeted screening with a risk-factor questionnaire was the most cost-effective option. Higher than a prevalence of 58.5%, universal TST was preferred. In the secondary model, targeted screening with a questionnaire followed by IGRA testing was cost-effective compared with no screening in the base case when the LTBI prevalence was >4.9%.

LIMITATIONS

There is no established gold standard for the diagnosis of LTBI. Results of any modeling task are limited by the accuracy of available data.

CONCLUSIONS

Prior to starting steroid therapy, only patients in areas with a high prevalence of LTBI will benefit from universal TST. As more evidence becomes available about the use of IGRA testing in children, the assay may become a component of cost-effective screening protocols in populations with a higher burden of LTBI.

Myasthenia gravis aggravated by steroid-induced isolated mediastinal tuberculous lymphadenitis

Background

Myasthenia gravis (MG) is occasionally aggravated by chronic infection, of which there are many kinds.

Case Report

We report herein the case of a 56-year-old woman with MG aggravated by the activation of isolated mediastinal tuberculous lymphadenitis (MTL) during corticosteroid administration. The possibility of MTL had been disregarded in the differential diagnosis of aggravation of MG weakness, because MTL without pulmonary manifestations is uncommon even in areas where tuberculosis is endemic.

Conclusions

This case suggests that chronic infections such as tuberculosis should be considered in myasthenic patients with progressive exacerbation if definite evidence for aggravating factors of MG is not obtained.

Comparison of interferon-gamma release assay versus tuberculin skin test for tuberculosis screening in inflammatory bowel disease

OBJECTIVES

Reactivation of latent tuberculosis (TB) in inflammatory bowel disease (IBD) patients treated with antitumor necrosis factor-alpha medication is a serious problem. Currently, TB screening includes chest x-rays and a tuberculin skin test (TST). The interferon-gamma release assay (IGRA) QuantiFERON-TB Gold In-Tube (QFT-G-IT) shows better specificity for diagnosing TB than the skin test. This study evaluates the two test methods among IBD patients.

METHODS

Both TST and IGRA were performed on 212 subjects (114 Crohn's disease, 44 ulcerative colitis, 10 indeterminate colitis, 44 controls).

RESULTS

Eighty-one percent of IBD patients were under immunosuppressive therapy; 71% of all subjects were vaccinated with Bacille Calmette Guérin; 18% of IBD patients and 43% of controls tested positive with the skin test (P < 0.0001). Vaccinated controls tested positive more often with the skin test (52%) than did vaccinated IBD patients (23%) (P = 0.011). Significantly fewer immunosuppressed patients tested positive with the skin test than did patients not receiving therapy (P = 0.007); 8% of patients tested positive with the QFT-G-IT test (14/168) compared to 9% (4/44) of controls. Test agreement was significantly higher in the controls (P = 0.044) compared to the IBD group.

CONCLUSIONS

Agreement between the two test methods is poor in IBD patients. In contrast to the QFT-G-IT test, the TST is negatively influenced by immunosuppressive medication and vaccination status, and should thus be replaced by the IGRA for TB screening in immunosuppressed patients having IBD.

Corticosteroids for bacterial corneal ulcers

AIMS

The aim of the study was to conduct a preliminary clinical trial to assess whether adjunctive topical corticosteroids improve outcomes in bacterial keratitis and, if no difference was found, to determine the feasibility and sample size necessary for conducting a larger trial to answer this question.

METHODS

In this single centre, double-masked clinical trial, 42 patients with culture-confirmed bacterial keratitis at Aravind Eye Hospital in India were randomised to receive either topical prednisolone phosphate or placebo. All patients received topical moxifloxacin. The primary outcome was best spectacle-corrected visual acuity (BSCVA) at 3 months, adjusting for enrolment BSCVA and arm. Other pre-specified outcomes included re-epithelialisation time, infiltrate/scar size and adverse events.

RESULTS

Compared with placebo, patients in the steroid group re-epithelialised more slowly (hazard ratio 0.47, 95% CI 0.23 to 0.94). There was no significant difference in BSCVA or infiltrate/scar size at 3 weeks or 3 months. To have 80% power to detect a two-line difference in acuity, 360 cases would be required.

CONCLUSIONS

Although corticosteroid treatment resulted in a statistically significant delay in re-epithelialisation, this did not translate to a significant difference in visual acuity, infiltrate/scar size or adverse events. To assess the effect of steroids on acuity, a larger trial is warranted and feasible.

Endobronchial tuberculosis presenting as right middle lobe syndrome: clinical characteristics and bronchoscopic findings in 22 cases

PURPOSE

Endobronchial tuberculosis (EBTB) presenting as right middle lobe syndrome (RMLS) is an uncommon clinical condition. We investigated the clinical characteristics in patients with EBTB presenting as RMLS.

PATIENTS AND METHODS

We retrospectively reviewed the records of 22 patients with EBTB presenting as RMLS who were diagnosed at our hospital from 2003 to 2006.

RESULTS

Its occurrence was more common in females than males (F, 18; M, 4). The mean age was 70.3 +/- 8.5 years, and 17 patients were above the age of 65 years. Cough with sputum was the most common manifestation and 2 patients were asymptomatic. In bronchoscopic analysis, the most common finding was edematous-type EBTB, which was found in 15 patients, followed by actively caseating type in 6 and tumorous type in 1. Acid-fast bacilli (AFB) staining for bronchial washing fluid was positive in only 5 patients: 1 with edematous type and 4 with actively caseating type. Bronchoscopic biopsy showed chronic granulomatous inflammation in 16 patients. Follow-up chest X-ray after treatment showed complete disappearance of the lesion in 2 patients, more than 50% improvement in 5, less than 50% improvement in 5, and no change of lesion in 4.

CONCLUSION

Edematous-type EBTB was the most common type of EBTB presenting as RMLS, and it usually occurred in elderly patients. Culturing for mycobacterium and histologic examination by bronchoscopy are necessary for proper diagnosis in these patients.

Corticosteroids for tuberculous pleurisy

BACKGROUND

Corticosteroids used in addition to antituberculous therapy have been reported to benefit people with tuberculous pleurisy. However, research findings are inconsistent, raising doubt as to whether such treatment is worthwhile. Concern also exists regarding the potential adverse effects of corticosteroids, especially in HIV-positive people.

OBJECTIVES

To evaluate the effects of adding corticosteroids to drug regimens for tuberculous pleural effusion.

SEARCH STRATEGY

In May 2007, we searched the Cochrane Infectious Diseases Group Specialized Register, CENTRAL (The Cochrane Library 2007, Issue 2), MEDLINE, EMBASE, LILACS, Current Controlled Trials, and reference lists of articles.

SELECTION CRITERIA

Randomized and quasi-randomized controlled trials comparing any corticosteroid with no treatment, placebo, or other active treatment (both groups should receive the same antituberculous drug regimen) in people diagnosed with tuberculous pleurisy.

DATA COLLECTION AND ANALYSIS

Two authors independently assessed trial methodological quality and extracted data. Data were analysed using relative risks (RR) and weighted mean difference (WMD) with 95% confidence intervals (CI). The fixed-effect model was applied in the absence of statistically significant heterogeneity.

MAIN RESULTS

Six trials with 633 participants met the inclusion criteria; one trial included only HIV-positive people. Compared to control, corticosteroid use was associated with less residual pleural fluid at four weeks (RR 0.76, 95% CI 0.62 to 0.94; 394 participants, 3 trials) and reduced pleural thickening (RR 0.69, 95% CI 0.51 to 0.94; 309 participants, 4 trials). We found no evidence of an effect of corticosteroids on death from any cause (194 participants, 1 trial), respiratory function (191 participants, 2 trials), residual pleural fluid at eight weeks (399 participants, 4 trials), or pleural adhesions (123 participants, 2 trials). Although discontinuation of treatment due to adverse events was more frequent in participants receiving corticosteroids than placebo (RR 2.80, 95% CI 1.12 to 6.98; 586 participants, 6 trials), the effects were generally mild. The risk of Kaposi sarcoma may be increased in HIV-positive people receiving corticosteroids (RR 13.00, 95% CI 0.74 to 227.63; 194 participants, 1 trial).

AUTHORS' CONCLUSIONS

There are insufficient data to support evidence-based recommendations regarding the use of adjunctive corticosteroids in people with tuberculous pleurisy. Randomized controlled trials that are sufficiently powered to evaluate the effects of corticosteroids on both morbidity and mortality are needed. The effects of corticosteroids on HIV-related complications, such as Kaposi sarcoma, should be assessed in people co-infected with HIV.

Type I Gaucher disease following chemotherapy for light chain multiple myeloma

Although plasma cell disorders, such as hypergammaglobulinemia and monoclonal gammopathy of undetermined significance (MGUS), are reported to occur at higher incidences in patients with Type I Gaucher disease (GD) than in the normal population, pure light chain multiple myeloma (LCMM) has never been described in this context. Our case is the first to highlight a patient with LCMM who developed clinically apparent GD only following chemotherapy and hematopoietic stem cell transplantation. Renal complications are also exceedingly rare in GD, but nephrotic syndrome is one of the presenting features in this patient. The findings from this case will have important screening and diagnostic implications for both clinicians and patients.

Tuberculous pseudoaneurysm of the femoral artery complicated by cutaneous tuberculosis of the foot: a case report

An infected pseudoaneurysm of the right common femoral artery in a 69-year-old patient receiving methotrexate therapy was confirmed to have been caused by Mycobacterium tuberculosis. After surgical excision of the aneurysm and revascularization using femoral vein, cutaneous manifestations of M tuberculosis infection in the foot complicated the course. We hypothesized that methotrexate may have triggered the reactivation of dormant tuberculosis in this patient. Because extrapulmonary tuberculous pseudoaneurysms are clinically similar to other types of infected pseudoaneurysm, M tuberculosis infection should always be suspected during the initial diagnosis. We propose that mycobacterial cultures should be routine when initial cultures and Gram stain are negative.

Safety and efficacy of intravesical bacillus Calmette-Guerin instillations in steroid treated and immunocompromised patients

PURPOSE

We assessed the safety and efficacy of intravesical bacillus Calmette-Guerin instillations in steroid treated and immunocompromised patients.

MATERIALS AND METHODS

We retrospectively reviewed the charts of 697 patients treated with bacillus Calmette-Guerin instillations at our institution from 1991 to 2004. In 24 patients (3.5%) an underlying comorbidity directly affecting the immune system was diagnosed before bacillus Calmette-Guerin administration or steroids were administered at least 6 weeks before and at the time of bacillus Calmette-Guerin instillations. The immunosuppressive effect of steroids was assessed by the percent of lymphocytes. End points were the bacillus Calmette-Guerin response at 6 months, defined as normal cystoscopy, cytology and biopsy when available, and treatment related toxicity.

RESULTS

Four patients (17%) had active lymphoma or chronic lymphocytic leukemia during bacillus Calmette-Guerin administration and 21 (88%) had a concurrent condition for which oral steroids (11), inhaled steroids (14) or oral and inhaled steroids (4) were administered. Patients treated with oral steroids had a lower percent of lymphocytes than patients treated with inhaled steroids and 15 age matched patients with high risk superficial bladder cancer and no steroid treatment (12.3% vs 17.5% and 18.6%, respectively). The overall bacillus Calmette-Guerin response rate at 6 months was 58%. Ten of the 24 patients had disease recurrence and 3 had disease progression at a median followup of 63.5 months (IQR 19.5, 89). One patient treated with oral steroids had self-limited febrile disease and worsening of myalgia 48 hours after his third bacillus Calmette-Guerin cycle. No other systemic adverse event following bacillus Calmette-Guerin therapy was recorded and all patients completed scheduled treatments.

CONCLUSIONS

Intravesical bacillus Calmette-Guerin is a viable therapeutic option in patients with high risk superficial bladder cancer and concomitant lymphoma or chronic lymphocytic leukemia, treatment with low dose oral steroids or treatment with inhaled steroids. The bacillus Calmette-Guerin response rate at 6 months and the side effects profile associated with bacillus Calmette-Guerin therapy in these patients were comparable to those in patients with no evidence of immunosuppression. Further studies are warranted to assess the safety and efficacy of bacillus Calmette-Guerin instillations in critically immunocompromised patients.

Serious infections associated with anticytokine therapies in the rheumatic diseases

The ability to target and neutralize macrophage-derived inflammatory cytokines, particularly tumor necrosis factor-alpha (TNF-alpha), has emerged in recent years as one of the most important advances in the treatment of rheumatoid arthritis, Crohn's disease, and several other systemic inflammatory diseases. In rheumatoid arthritis, for example, these biological agents rapidly reduce signs and symptoms of joint inflammation and profoundly slow the progression of joint damage. However, data that have emerged following Food and Drug Administration approval of these agents have alerted clinicians to an increased likelihood of opportunistic infections in patients treated with these agents, particularly tuberculosis. The effect of TNF inhibition on the frequency of infection with more common bacterial pathogens is less clear. Animal models of tuberculosis and other opportunistic infections have demonstrated the importance of TNF-alpha in controlling and containing intracellular pathogens. The spectrum of infections reported to date in the setting of anti-TNF-alpha treatment is reviewed here. In addition, relevant animal data illustrating potential mechanistic roles for TNF-alpha in host responses to infection are also reviewed.

Endobronchial tuberculosis

Endobronchial tuberculosis is defined as tuberculous infection of the tracheobronchial tree. Although clinical features differ between various types and stages of endobronchial tuberculosis, common symptoms are cough, hemoptysis, sputum production, wheezing, chest pain, fever and dyspnea. Endobronchial tuberculosis is difficult to diagnose, because the lesion is not evident in the chest radiograph. Computerized tomography is very useful in evaluating bronchial lesions such as stenosis or obstruction. The most important goal of treatment in active endobronchial tuberculosis is the eradication of tubercle bacilli. The second most important goal is prevention of bronchial stenosis. Corticosteroid therapy for prevention of bronchial stenosis in endobronchial tuberculosis remains controversial, but the best results are associated with minimal delay in the initiation of steroid treatment. In inactive disease, treatment to restore full patency is appropriate. As steroids or other medication are unable to reverse stenosis from fibrous disease, airway patency must be restored mechanically by surgery or endobronchial intervention. Aerosol therapy with streptomycin and corticosteroids is useful in treatment against active endobronchial tuberculosis. Time to healing of ulcerous lesions is shorter, and bronchial stenosis is less severe in patients on aerosol therapy. Progression to bronchial stenosis may be prevented if the therapy is initiated as soon as possible.

Therapeutic management of endobronchial tuberculosis

Endobronchial tuberculosis (EBTB) is defined as tuberculous infection of the tracheobronchial tree. Common symptoms are cough, haemoptysis, sputum production, wheezing, chest pain and fever in active disease and dyspnoea and wheezing in the fibrous stage. This form of tuberculosis is difficult to diagnose because the lesion is not evident in the chest radiograph, frequently delaying treatment. Computed tomography is very useful in evaluating bronchial lesions such as stenosis or obstruction. The most important goal of treatment in active EBTB is eradication of tubercle bacilli. The second most important goal is prevention of bronchial stenosis. Corticosteroid therapy for the prevention of bronchial stenosis in EBTB remains controversial. However, the healing time of ulcerous lesions was shorter and bronchial stenosis was less severe, in patients treated with aerosol therapy, consisting of streptomycin 100 mg, a corticosteroid (dexamethasone 0.5 mg) and naphazoline 0.1 mg administered twice-daily along with conventional oral therapy. In inactive disease, treatment to restore full patency is appropriate. As steroids or other medications are unable to reverse stenosis from fibrous disease, airway patency must be restored mechanically by surgery or endobronchial intervention. Effectiveness and complications remain important issues with the mechanical techniques as use and evaluation continue. Corticosteroid therapy for prevention of bronchial stenosis in EBTB remains controversial. Our observations suggest that progression of bronchial stenosis can be prevented in patients who are treated with aerosol therapy with corticosteroids.

Stress causes a further decrease in immunity to herpes simplex virus-1 in immunocompromised hosts

Physical or psychological stress can modulate immune responses in normal subjects. The effects of stress on immunity in immunocompromised hosts, however, have not been extensively investigated. Here we assess relationships among footshock stress (FS), infection with herpes simplex virus-1 (HSV-1), and immunosuppression by cyclophosphamide (CY) during the active immune response to virus in BALB/c mice. Without FS, CY significantly decreased survival and body weight gain, splenic leukocyte numbers, in vivo serum cytokine level and in vitro splenocyte cytokine production during HSV-1 infection. FS alone also significantly inhibited cell mediated anti-viral responses to HSV-1. However, FS in combination with certain CY doses led to a further significant decrease in host responses compared to either CY or FS treatment alone, including decreased survival rate, increased weight loss, lowered leukocyte numbers, reduced cytokine production in vivo and in vitro, and decreased numbers of cytokine-producing cells (IL-12 and IFNgamma). In contrast, CY, but not FS, significantly reduced in vivo anti-HSV-1 antibody secretion. These data support the hypothesis that stress can further reduce host immune responses in immunocompromised individuals. Thus, stress levels of patients should be taken into consideration prior to clinical treatment with immunosuppressants.

Congenital tuberculosis requiring extracorporeal membrane oxygenation

We describe a 6-week-old infant with congenital tuberculosis with cardiorespiratory failure. She was successfully treated with ECMO initiated after worsening hypoxemia despite mechanical ventilation.

Suggested guidelines for screening and management of tuberculosis in patients taking oral glucocorticoids--an important but often neglected issue

One third of the world's population is infected with tuberculosis and its incidence is increasing. Systemic glucocorticoids are the mainstay of immunosuppressive therapy for immunobullous diseases and collagen vascular diseases in dermatology. Patients who are given prolonged glucocorticoid therapy may be at risk for both the acquisition of primary tuberculosis and the reactivation of nonactive tuberculosis. The purpose of this article is to highlight the importance of screening for tuberculosis and its management in this group of patients, as there are no published guidelines in the dermatology literature on this subject. We summarize the methods used for tuberculosis screening, give an account of treatment regimens for the various types of tuberculosis infection, and suggest a practical approach to screening and management of tuberculosis in patients receiving long-term glucocorticoid therapy.

Anti-tumour necrosis factor agents and tuberculosis risk: mechanisms of action and clinical management

Cases of active tuberculosis have been reported worldwide with the use of therapeutic agents that inhibit tumour necrosis factor (TNF) alpha. TNFalpha has a central role in mycobacterial infection and disease. Accordingly, progression of recently acquired tuberculosis infection or reactivation of remotely acquired infection should be expected with the use of anti-TNF agents. The available in-vitro and epidemiological evidence for the two currently approved agents, infliximab and etanercept, shows that the risk of development of active tuberculosis is greater with infliximab. Tuberculin skin testing (TST) should be undertaken before any significant immunosuppressive therapy including these agents, though the possibility of false-negative reactions in immunocompromised populations must be borne in mind. A positive TST should be followed by medical assessment and chest radiography, as well as by other tests judged appropriate by the physician to identify active disease. Active tuberculosis must be treated appropriately before initiation of treatment with an anti-TNF agent. Treatment of latent tuberculosis can be considered on an individual basis for TST-negative patients receiving anti-TNF agents when significant risk factors for infection are present.

Epiglottic Tuberculosis in a Patient Treated with Steroids for Addison's Disease

Isolated epiglottic tuberculosis (TBC) is uncommon and has rarely been described. We report the case of a 40-year-old man with tuberculous involvement of the epiglottis and primary adrenal insufficiency. Endoscopic examination showed a severely swollen epiglottis with granulomatous and partially necrotic mucosa. The patient has been treated with glucocorticoids for four years due to primary adrenocortical insufficiency. We therefore assume that tuferculous involvement of epiglottis is due to the reactivation of pulmonary TBC. We also discuss differential diagnosis and management of epiglottic TBC and Addison's disease.

Use of IMiD3, a thalidomide analog, as an adjunct to therapy for experimental tuberculous meningitis

Tuberculous meningitis (TBM), the most severe form of Mycobacterium tuberculosis infection in humans, is associated with significant morbidity and mortality despite successful treatment with antituberculous drugs. This is due to the irreversible brain damage subsequent to the local inflammatory response of the host to M. tuberculosis. Corticosteroids have been used in conjunction with antituberculous therapy in an attempt to modulate the inflammatory response, but this strategy has been of limited success. Therefore, we examined whether combining antituberculous drugs with the immunomodulatory drug thalidomide or with a new thalidomide analog, immunomodulatory drug 3 (IMiD3), would be effective in reducing morbidity and mortality in an experimental rabbit model of TBM. Intracisternal inoculation of 5 x 10(4) CFU of Mycobacterium bovis Ravenel in rabbits induced progressive subacute meningitis characterized by high cerebrospinal fluid (CSF) leukocytosis, protein influx, release of tumor necrosis factor (TNF), substantial meningeal inflammation, and mortality by day 28. Treatment with antituberculous drugs or with antituberculous drugs plus thalidomide improved the clinical course of disease somewhat and increased survival to about 50%. In contrast, treatment with antituberculous drugs in combination with IMiD3 limited pathological neurologic changes and resulted in marked improvement (73%) in survival. IMiD3 treatment was also associated with reduced leukocytosis in the CSF and significantly lower levels of TNF in CSF and plasma. Histologically, the meningeal inflammation in animals treated with antituberculous drugs plus IMiD3 was considerably attenuated compared to that of the other treatment groups. These results suggest a potential role for IMiD3 in the management of TBM in patients.

Interventions for treating tuberculous pericarditis

BACKGROUND

Tuberculous pericarditis - tuberculosis infection of the pericardial membrane (pericardium) covering the heart - is becoming more common. The infection can result in fluid around the heart or fibrosis of the pericardium, which can be fatal.

OBJECTIVES

In people with tuberculous pericarditis, to evaluate the effects on death, life-threatening conditions, and persistent disability of: (1) 6-month antituberculous drug regimens compared with regimens of 9 months or more; (2) corticosteroids; (3) pericardial drainage; and (4) pericardiectomy.

SEARCH STRATEGY

We searched the Cochrane Infectious Diseases Group trials register (June 2002), the Cochrane Controlled Trials Register (Issue 2, 2002), MEDLINE (1966 to June 2002), EMBASE (1980 to May 2002), and checked the reference lists of existing reviews. We also contacted organizations and individuals working in the field.

SELECTION CRITERIA

Randomized and quasi-randomized controlled trials of treatments for tuberculous pericarditis.

DATA COLLECTION AND ANALYSIS

Two reviewers independently assessed trial quality and extracted data. Meta-analysis using fixed effects models calculated summary statistics, provided there was no statistically significant heterogeneity, and expressed results as relative risk. Study authors were contacted for additional information.

MAIN RESULTS

Four trials met the inclusion criteria, with a total of 469 participants. Treatments tested were adjuvant steroids and surgical drainage. Two trials with a total of 383 participants tested adjuvant steroids in participants with suspected tuberculous pericarditis in the pre-HIV era. Fewer participants died in the intervention group, but numbers were small (relative risk [RR] 0.65; 95% confidence interval [CI] 0.36 to 1.16, n = 350). One small trial tested steroids in HIV positive participants with effusion showed a similar pattern (RR 0.50; 95% CI 0.19 to 1.28, n = 58). One trial examined open surgical drainage compared with conservative management, and showed surgery relieved cardiac tamponade.

REVIEWER'S CONCLUSIONS

Steroids could have important clinical benefits, but the trials published to date are too small to demonstrate an effect. This requires large placebo controlled trials. Subgroup analysis could explore whether effusion or fibrosis modify the effects. Therapeutic pericardiocentesis under local anaesthesia and pericardiectomy also require further evaluation.

Depletion of CD4(+) T cells causes reactivation of murine persistent tuberculosis despite continued expression of interferon gamma and nitric oxide synthase 2

Tuberculosis is a major cause of death in much of the world. Current estimates are that one-third of the world's population is infected with Mycobacterium tuberculosis. Most infected persons control the infection but in many cases may not eliminate the organism. Reactivation of this clinically latent infection is responsible for a large proportion of active tuberculosis cases. A major risk factor for reactivation of latent tuberculosis is HIV infection, suggesting a role for the CD4(+) T cell subset in maintaining the latent persistent infection. In this study, we tested the requirement for CD4(+) T cells in preventing reactivation in a murine model of latent tuberculosis. Antibody-mediated depletion of CD4(+) T cells resulted in rapid reactivation of a persistent infection, with dramatically increased bacterial numbers in the organs, increased pathology in the lungs, and decreased survival. Although CD4(+) T cells are believed to be a major source of interferon (IFN)-gamma, expression of the gene for IFN-gamma in the lungs of CD4(+) T cell-depleted mice was similar to that in control mice. In addition, inducible nitric oxide synthase production and activity was unimpaired after CD4(+) T cell depletion, indicating that macrophage activation was present even during CD4(+) T cell deficiency. These data indicate that CD4(+) T cells are necessary to prevent reactivation but may have roles in addition to IFN-gamma production and macrophage activation in controlling a persistent tuberculous infection.

IL-10-producing T cells suppress immune responses in anergic tuberculosis patients

The lethality of Mycobacterium tuberculosis remains the highest among infectious organisms and is linked to inadequate immune response of the host. Containment and cure of tuberculosis requires an effective cell-mediated immune response, and the absence, during active tuberculosis infection, of delayed-type hypersensitivity (DTH) responses to mycobacterial antigens, defined as anergy, is associated with poor clinical outcome. To investigate the biochemical events associated with this anergy, we screened 206 patients with pulmonary tuberculosis and identified anergic patients by their lack of dermal reactivity to tuberculin purified protein derivative (PPD). In vitro stimulation of T cells with PPD induced production of IL-10, IFN-gamma, and proliferation in PPD(+) patients, whereas cells from anergic patients produced IL-10 but not IFN-gamma and failed to proliferate in response to this treatment. Moreover, in anergic patients IL-10-producing T cells were constitutively present, and T-cell receptor-mediated (TCR-mediated) stimulation resulted in defective phosphorylation of TCRzeta and defective activation of ZAP-70 and MAPK. These results show that T-cell anergy can be induced by antigen in vivo in the intact human host and provide new insights into mechanisms by which M. tuberculosis escapes immune surveillance.

Inhaled corticosteroid therapy is safe in tuberculin-positive asthmatic children

BACKGROUND

Although treatment with oral corticosteroids can cause reactivation of latent Mycobacterium tuberculosis (TB) infection in purified protein derivative (PPD)-positive individuals with no evidence of clinical disease, little is known about the effects of inhaled corticosteroids in this respect.

OBJECTIVE

This study was undertaken to assess whether inhaled corticosteroid (CS) therapy reactivates latent TB infection in PPD-positive asthmatic children.

METHOD

We studied 32 PPD skin test-positive (> or =10 mm) children [age (mean +/- SD), 7.9 +/- 4.1 years] with no family history and no evidence of TB infection on chest radiograms who were receiving inhaled budesonide for the treatment of asthma. They were further evaluated with thorax computed tomography (CT) and erythrocyte sedimentation rate and closely observed for an additional 9 months.

RESULTS

At enrollment the mean diameter of PPD reaction was 12.8 +/- 2.7 mm. The mean duration of inhaled CS treatment and the mean cumulative CS dose were 9.8 +/- 7.6 months and 275 +/-199 mg, respectively. Thorax CT studies revealed mediastinal lymph nodes in 7 of the 32 patients. There was no significant difference between children with and without mediastinal lymph nodes according to age, gender, size of PPD skin testing, erythrocyte sedimentation rate and duration and cumulative CS dose of inhaled budesonide therapy before study. A second thorax CT was obtained 9 months later in those 7 patients with lymphadenopathy (additional mean cumulative CS dose, 222.57 mg). There was no change in the size of their lymph nodes.

CONCLUSION

Long term inhaled budesonide therapy appears to be safe in PPD-positive asthmatic children.

Reactivation of latent tuberculosis: variations on the Cornell murine model

Mycobacterium tuberculosis causes active tuberculosis in only a small percentage of infected persons. In most cases, the infection is clinically latent, although immunosuppression can cause reactivation of a latent M. tuberculosis infection. Surprisingly little is known about the biology of the bacterium or the host during latency, and experimental studies on latent tuberculosis suffer from a lack of appropriate animal models. The Cornell model is a historical murine model of latent tuberculosis, in which mice infected with M. tuberculosis are treated with antibiotics (isoniazid and pyrazinamide), resulting in no detectable bacilli by organ culture. Reactivation of infection during this culture-negative state occurred spontaneously and following immunosuppression. In the present study, three variants of the Cornell model were evaluated for their utility in studies of latent and reactivated tuberculosis. The antibiotic regimen, inoculating dose, and antibiotic-free rest period prior to immunosuppression were varied. A variety of immunosuppressive agents, based on immunologic factors known to be important to control of acute infection, were used in attempts to reactivate the infection. Although reactivation of latent infection was observed in all three variants, these models were associated with characteristics that limit their experimental utility, including spontaneous reactivation, difficulties in inducing reactivation, and the generation of altered bacilli. The results from these studies demonstrate that the outcome of Cornell model-based studies depends critically upon the parameters used to establish the model.

T cell mediated immunity to Mycobacterium tuberculosis

Recent advances in the characterization of the protective immune response to mycobacteria have highlighted the central role of phenotypically and functionally distinct subsets of T cells. These T cell subsets not only contribute to host defense by the secretion of macrophage-activating cytokines, but also by lysing the host cell. Besides releasing intracellular pathogens, which can then be taken up and killed by newly recruited macrophages, it has now been demonstrated that lysis of infected targets by one subset of cytolytic T cells can directly kill Mycobacterium tuberculosis.

Down-Regulation of CD1 on Antigen-Presenting Cells by Infection with Mycobacterium tuberculosis

Intracellular pathogens have developed efficient evasion strategies to survive the defenses of the host immune system. In this study, we describe a new escape mechanism utilized by Mycobacterium tuberculosis that involves the down-regulation of the Ag-presenting molecule CD1 from the cell surface of CD1+ APCs. The loss of CD1 from the cell surface is associated with a complete inhibition of the ability of the infected cells to present Ag to CD1-restricted T cells. The down-regulation of Ag-presenting molecules on CD1+ APC by infection with M. tuberculosis is unique for CD1, since the expression of the classical Ag-presenting molecules MHC class I and MHC class II is not influenced. Our data show that efficient down-regulation of CD1 requires infection of the cells with live mycobacteria, since heat killing of the bacteria completely abrogates the effect. The observed down-regulation is not due to the secretion of cytokines or other host- or pathogen-derived factors. Investigation of upstream events responsible for the down-regulation of CD1 revealed that infection with live M. tuberculosis decreased the steady state CD1-mRNA levels. This study introduces a novel evasion mechanism of M. tuberculosis that could contribute to persistence of intracellular infection by avoiding immune recognition.

Pneumocystis carinii colonization in the absence of immunosuppression

A prospective study was undertaken to evaluate the incidence and the course of Pneumocystis carinii colonization in immunocompetent patients with severe pulmonary diseases. A further perspective was to determine the diagnostic values of different detection methods. Bronchoalveolar lavage fluid samples from 77/838 adult HIV-negative patients were examined by Diff-Quik stain, direct immunofluorescence test and polymerase chain reaction. All Diff-Quik stains were negative, but direct immunofluorescence tests and polymerase chain reactions were positive in the samples of 5 patients. The normal number of granulocytes and CD4+T- lymphocytes (median 810 cells/microliters) and normal values of immunoglobulins proved the relative competence of the immune systems of the 77 patients. Although none of these patients received any agent effective against P. carinii, none developed a P. carinii pneumonia within a 120.5-d surveillance period. Nosocomial transmission could be excluded. As the colonization with P. carinii did not result in pneumonia in immunocompetent patients, clinically silent carriers have to be assumed. In non-AIDS patients, sensitive detection methods have to be used to identify colonized persons.