Effect of cigarette smoking on sputum smear conversion in adults with active pulmonary tuberculosis

Is Tobacco Use Associated With Risk of Recurrence and Mortality Among People With TB?: A Systematic Review and Meta-Analysis

BACKGROUND

Associations between tobacco use and poor TB treatment outcomes are well documented. However, for important outcomes such as TB recurrence or relapse and mortality during treatment, as well as for associations with smokeless tobacco (ST), the evidence is not summarized systematically.

RESEARCH QUESTION

Is tobacco use associated with risk of poor treatment outcomes among people with TB?

STUDY DESIGN AND METHODS

The MEDLINE, Embase, and Cumulative Index of Nursing and Allied Health Literature databases were searched on November 22, 2021. Epidemiologic studies reporting associations between tobacco use and at least one TB treatment outcome were eligible. Independent double-screening, extractions, and quality assessments were undertaken. Random effects meta-analyses were conducted for the two primary review outcomes (TB recurrence or relapse and mortality during treatment), and heterogeneity was explored using subgroups. Other outcomes were synthesized narratively.

RESULTS

Our searches identified 1,249 records, of which 28 were included in the meta-analyses. Based on 15 studies, higher risk of TB recurrence or relapse was found with ever using tobacco vs never using tobacco (risk ratio [RR], 1.78; 95% CI, 1.31-2.43; I2 = 85%), current tobacco use vs no tobacco use (RR, 1.95; 95% CI, 1.59-2.40; I2 = 72%), and former tobacco use vs never using tobacco (RR, 1.84; 95% CI, 1.21-2.80; I2 = 4%); heterogeneity arose from differences in study quality, design, and participant characteristics. Thirty-eight studies were identified for mortality, of which 13 reported mortality during treatment. Ever tobacco use (RR, 1.55; 95% CI, 1.32-1.81; I2 = 0%) and current tobacco use (RR, 1.51; 95% CI, 1.09-2.10; I2 = 87%) significantly increased the likelihood of mortality during treatment among people with TB compared with never using tobacco and not currently using tobacco, respectively; heterogeneity was explained largely by differences in study design. Almost all studies in the meta-analyses scored high or moderate on quality assessments. Narrative synthesis showed that tobacco use was a risk factor for other unfavorable TB treatment outcomes, as previously documented. Evidence on ST was limited, but identified studies suggested an increased risk for poor outcomes with its use compared with not using it.

INTERPRETATION

Tobacco use significantly increases the risk of TB recurrence or relapse and mortality during treatment among people with TB, highlighting the need to address tobacco use to improve TB outcomes.

TRIAL REGISTRY

PROSPERO; No.: CRD42017060821; URL: https://www.crd.york.ac.uk/prospero/.

Clinico-radiological particularities of common pulmonary tuberculosis among smokers in Tunisia

INRODUCTION

Smoking and tuberculosis are two major public health issues worldwide, particularly in emerging countries. Currently, the relationship between these two scourges is well established.

AIM

Describe the clinical, radiological and progressive features of common pulmonary tuberculosis in smokers.

METHODS

Comparative study, carried out at the Pneumology department of the Hédi Chaker in Sfax, Tunisia, including 120 patients hospitalized for common pulmonary tuberculosis  from January 2014 to December 2016 and who completed their follow-ups for a minimum period of 2 years . The patients were divided into 2 groups: Group1 (G1) consisting of 60 smoking patients and Group 2 (G2) consisting of 60 non-smoking patients. To assess the severity of radiological lesions, we used the International Labour Organization classification for simple pneumoconiosis and the Brouet classification.

RESULTS

The mean age of the patients was comparable in the two groups with a predominance of male for G1 (91%) and female for G2 (70%). The smokers consulted later (113 days versus 60 days (p=0.023). Dyspnea, hemoptysis and chest pain were significantly more frequent in the smokers. The radiological lesions were more serious in smoking group. Bilateral lesions were more observed in smokers (58% vs 25% p = 0.004). A positive association was noted between the extent of radiological lesions, stage 3 and 4 according to the Brouet classification, and smoking status (p <0.001). Similarly for the International Labour Organization classification for simple pneumoconiosis , the radiological lesions were more severe (scores 6 - 15) in the smokers (p <0.001).Smoking was associated with poor adherence (p <0.008), prolonged anti-tuberculosis treatment (p <0.001), delayed RBK negativation in sputum (p <0.001), and more frequent reactivation of tuberculosis (p=0.001). After the diagnosis of CPT, 83% of patients continued to smoke at the same rate and only 7% of patients had quit smoking.

CONCLUSION

Smoking worsens CPT by making the clinical picture noisier, radiological lesions more aggressive, negativation of BK in sputum later, and reactivation of CPT more frequent.

The impact of smoking on tuberculosis treatment outcomes: a meta-analysis

BACKGROUND: Cigarette smoking contributes to tuberculosis (TB) epidemiology. However, limited evidence exists on how smoking impacts TB treatment outcomes such as treatment loss to follow-up and culture conversion.METHODS: This meta-analysis assessed current evidence of the impact of active cigarette smoking on TB treatment outcomes. PubMed, Scopus, Embase, and the Cochrane Library were searched for English-language articles published from database inception through 2017. Articles addressing active pulmonary TB and cigarette smoking were identified and data abstracted. Smokers were defined as those who smoked every day or some days at the time of interview/diagnosis. Non-smokers did not smoke at the time of interview/diagnosis. Unfavorable outcomes included any outcome other than cure or completion of TB treatment. Three different data sets were examined: 8 articles addressing unfavorable treatment outcomes, 9 analyzing only treatment loss to follow-up, and 5 addressing delayed smear or culture conversion. Studies that had <20 subjects or that addressed only populations with comorbidities were excluded.RESULTS: We identified 1030 studies; 21 studies fulfilled the inclusion/exclusion criteria. Smokers had greater odds of unfavorable outcomes (pooled odds ratio [pOR] 1.23, 95%CI 1.14-1.33), delayed smear or culture conversion (pOR 1.55, 95%CI 1.04-2.07), and treatment loss to follow-up (pOR 1.35, 95%CI 1.21-1.50).CONCLUSION: Cigarette smoking is associated with negative treatment results and delayed conversion to negative smear or culture, suggesting smoking is an important factor for consideration in TB elimination efforts.

Dynamics of sputum conversion during effective tuberculosis treatment: A systematic review and meta-analysis

BACKGROUND

Two weeks' isolation is widely recommended for people commencing treatment for pulmonary tuberculosis (TB). The evidence that this corresponds to clearance of potentially infectious tuberculous mycobacteria in sputum is not well established. This World Health Organization-commissioned review investigated sputum sterilisation dynamics during TB treatment.

METHODS AND FINDINGS

For the main analysis, 2 systematic literature searches of OvidSP MEDLINE, Embase, and Global Health, and EBSCO CINAHL Plus were conducted to identify studies with data on TB infectiousness (all studies to search date, 1 December 2017) and all randomised controlled trials (RCTs) for drug-susceptible TB (from 1 January 1990 to search date, 20 February 2018). Included articles reported on patients receiving effective treatment for culture-confirmed drug-susceptible pulmonary TB. The outcome of interest was sputum bacteriological conversion: the proportion of patients having converted by a defined time point or a summary measure of time to conversion, assessed by smear or culture. Any study design with 10 or more particpants was considered. Record sifting and data extraction were performed in duplicate. Random effects meta-analyses were performed. A narrative summary additionally describes the results of a systematic search for data evaluating infectiousness from humans to experimental animals (PubMed, all studies to 27 March 2018). Other evidence on duration of infectiousness-including studies reporting on cough dynamics, human tuberculin skin test conversion, or early bactericidal activity of TB treatments-was outside the scope of this review. The literature search was repeated on 22 November 2020, at the request of the editors, to identify studies published after the previous censor date. Four small studies reporting 3 different outcome measures were identified, which included no data that would alter the findings of the review; they are not included in the meta-analyses. Of 5,290 identified records, 44 were included. Twenty-seven (61%) were RCTs and 17 (39%) were cohort studies. Thirteen studies (30%) reported data from Africa, 12 (27%) from Asia, 6 (14%) from South America, 5 (11%) from North America, and 4 (9%) from Europe. Four studies reported data from multiple continents. Summary estimates suggested smear conversion in 9% of patients at 2 weeks (95% CI 3%-24%, 1 single study [N = 1]), and 82% of patients at 2 months of treatment (95% CI 78%-86%, N = 10). Among baseline smear-positive patients, solid culture conversion occurred by 2 weeks in 5% (95% CI 0%-14%, N = 2), increasing to 88% at 2 months (95% CI 84%-92%, N = 20). At equivalent time points, liquid culture conversion was achieved in 3% (95% CI 1%-16%, N = 1) and 59% (95% CI 47%-70%, N = 8). Significant heterogeneity was observed. Further interrogation of the data to explain this heterogeneity was limited by the lack of disaggregation of results, including by factors such as HIV status, baseline smear status, and the presence or absence of lung cavitation.

CONCLUSIONS

This systematic review found that most patients remained culture positive at 2 weeks of TB treatment, challenging the view that individuals are not infectious after this interval. Culture positivity is, however, only 1 component of infectiousness, with reduced cough frequency and aerosol generation after TB treatment initiation likely to also be important. Studies that integrate our findings with data on cough dynamics could provide a more complete perspective on potential transmission of Mycobacterium tuberculosis by individuals on treatment.

TRIAL REGISTRATION

Systematic review registration: PROSPERO 85226.

Smoking increases the risk of infectious diseases: A narrative review

Smoking is relevant to infectious diseases resulting in increased prevalence and mortality. In this article, we aim to provide an overview of the effects of smoking in various infections and to explain the potential mechanisms. We searched PubMed and other relevant databases for scientific studies that explored the relationship between smoking and infection. The mechanisms of susceptibility to infection in smokers may include alteration of the structural, functional and immunologic host defences. Smoking is one of the main risk factors for infections in the respiratory tract, digestive tract, reproductive tract, and other systems in humans, increasing the prevalence of HIV, tuberculosis, SARS-CoV, and the current SARS-CoV-2. Smoking cessation can reduce the risk of infection. Smoking increases the incidence of infections and aggravates the progress and prognosis of infectious diseases in a dose-dependent manner. Smoking cessation promotion and education are the most practical and economical preventive measures to reduce aggravation of disease infection owing to tobacco use.

Design, development and randomised controlled trial of a smartphone application, 'QinTB', for smoking cessation in tuberculosis patients: study protocol

INTRODUCTION

Providing smoking cessation treatment is an important intervention for tuberculosis (TB) patients. Mobile technologies, such as smartphone applications, have shown promising potential. However, there are few effective applications that could support TB patients in their efforts to quit smoking. To address this problem, we will develop a smartphone application 'QinTB' to help TB patients quit smoking, and we will evaluate the clinical efficacy of this application by using a randomised controlled trial (RCT).

METHODS AND ANALYSIS

This is a two-step study. In the first step, we will develop a smartphone application based on an interactive application of the transtheoretical model and protection motivation theory. Then, we will perform an RCT using a two-arm design; a total of 400 patients will be randomly assigned to the application group or the doctors' advice group; both treatments will be 6 months and follow-up will be 12 months; the primary outcome is the biochemically verified 6 month sustained abstinence rate; data will be analysed on an intention-to-treat basis.

ETHICS AND DISSEMINATION

This study was approved by the Ethics Committee of Beijing Research Institute for Tuberculosis Control and Prevention. We will disseminate the findings of this study through peer-reviewed publications and conference presentations.

TRIAL REGISTRATION NUMBER

This study was registered in the Chinese Clinical Trial Registry (ChiCTR1900022008) and the stage is Pre-results.

Pediatric Tuberculosis in a Northeast State of Peninsular Malaysia: Diagnostic Classifications and Determinants

Objectives

We sought to determine the total proportion of pediatric tuberculosis cases, characterize tuberculosis by its anatomical location and pretreatment sputum smear status, and to determine the association of the sociodemographic and clinical factors with tuberculosis disease among pediatric patients in Kelantan from 2012 until 2015.

Methods

We conducted a comparative cross-sectional study between tuberculosis cases and tuberculosis contacts among pediatric patients using the Tuberculosis Information System as a source population. All notified cases that fulfilled the inclusion and exclusion criteria were included in the study. Descriptive statistics, simple and multiple logistic regressions were used for data analysis.

Results

Of 5412 tuberculosis cases, 456 (8.4%) were pediatric patients with a mean age of 15.9 years. The majority had the pulmonary form of tuberculosis (78.1%) followed by the extrapulmonary (14.9%) and pulmonary form with concomitant extrapulmonary (7.0%) forms. Of all pulmonary tuberculosis cases, 64.9% were sputum smear-positive, and 35.1% were sputum smear-negative. Among 322 pediatric patients with tuberculosis, the majority were Malay (90.7%), 8.4% were illiterate, and 79.5% resided in non-urban areas. Of all cases, 2.8% were HIV-positive, and 14.6% were cigarette smokers. Older age, Malay ethnicity, female gender, non-urban residence, good education level, and cigarette smoking were the significant associated factors for tuberculosis disease among pediatric patients with an adjusted odds ratio (aOR) of 1.41 (95% confidence interval (CI): 1.29–1.54; p < 0.001), 0.17 (95% CI: 0.07–0.44; p < 0.001), 1.88 (95% CI: 1.33–2.65; p < 0.001), 1.92 (95% CI: 1.33–2.79; p = 0.001), 0.20 (95% CI: 0.12–0.33; p < 0.001), and 3.35 (95% CI: 1.86–6.01; p < 0.001), respectively.

Conclusions

The study will assist practices of tuberculosis detection and control management in the local setting and may help other national tuberculosis programs to review their detection criteria with similar statistics.

Effectiveness of pharmaceutical care on treatment outcomes for patients with first-time pulmonary tuberculosis in China

WHAT IS KNOWN AND OBJECTIVE

In this study, the effectiveness of pharmaceutical care on treatment outcomes for patients with first-time pulmonary tuberculosis in China was assessed.

METHODS

In this study, patients were randomized either to the usual care (UC) group (n = 72) where patients received routine medical and nursing care or to the pharmaceutical care (PC) group (n = 59) where patients were simultaneously provided with pharmaceutical care. The primary objectives were to evaluate whether treatment outcomes and patient adherence improved more in the PC group than in the UC group. In addition, in PC group, outcomes included the number of patient-reported pharmaceutical care issues and pharmacists' interventions.

RESULTS AND DISCUSSION

As compared to the UC group, treatment success rate was improved in the PC group, but the difference was not statistically significant (71% vs 54%; P = 0.137). However, as compared to the UC group, the number of patients who attended all of the scheduled visits was higher in the PC group; the difference was statistically significant (81% vs 60%, P = 0.018). Furthermore, the number of patients who had positive test results for all of the isoniazid tests was higher in the PC group than in the UC group; the difference was also statistically significant (80% vs 50%, P = 0.002). The consumed medication rate was improved in the PC group, but no significant difference was found between the two groups. The patient-reported pharmaceutical care issues mainly included dermatological, gastrointestinal, hepatic, metabolic, sensory, central nervous system and haematological problems. On the basis of clinical examination, laboratory parameters and drug information database, the pharmacists addressed most of these pharmaceutical care issues.

WHAT IS NEW AND CONCLUSION

Pharmaceutical care might improve patient adherence for patients with first-time pulmonary tuberculosis in China, and further, rigorously controlled trials are required.

Assessment of the influence of direct tobacco smoke on infection and active TB management

BACKGROUND

Smoking is a risk factor for tuberculosis (TB) infection and disease progression. Tobacco smoking increases susceptibility to TB in a variety of ways, one of which is due to a reduction of the IFN-γ response. Consequently, an impaired immune response could affect performance of IFN-γ Release Assays (IGRAs).

OBJECTIVE

In the present study, we assess the impact of direct tobacco smoking on radiological manifestations, sputum conversion and immune response to Mycobacterium tuberculosis, analyzing IFN-γ secretion by IGRAs.

METHODS

A total of 525 participants were studied: (i) 175 active pulmonary TB patients and (ii) 350 individuals coming from contact tracing studies, 41 of whom were secondary TB cases. Clinical, radiological and microbiological data were collected. T-SPOT.TB and QFN-G-IT were processed according manufacturer's instructions.

RESULTS

In smoking patients with active TB, QFN-G-IT (34.4%) and T-SPOT.TB (19.5%) had high frequencies of negative results. In addition, by means of an unconditional logistic regression, smoking was a main factor associated with IGRAs' false-negative results (aOR: 3.35; 95%CI:1.47-7.61; p<0.05). Smoking patients with active TB presented a high probability of having cavitary lesions (aOR: 1.88; 95%CI:1.02-3.46;p<0.05). Mean culture negativization (months) ± standard deviation (SD) was higher in smokers than in non-smokers (2.47±1.3 versus 1.69±1.4). Latent TB infection (LTBI) was favored in smoking contacts, being a risk factor associated with infection (aOR: 11.57; 95%CI:5.97-22.41; p<0.00005). The IFN-γ response was significantly higher in non-smokers than in smokers. Smoking quantity and IFN-γ response analyzed by IGRAs were dose-dependent related.

CONCLUSIONS

Smoking had a negative effect on radiological manifestations, delaying time of sputum conversion. Our data establish a link between tobacco smoking and TB due to a weakened IFN-γ response caused by direct tobacco smoke.

The impact of diabetics and smoking on gender differences of smear positive pulmonary tuberculosis incidence

BACKGROUND

Several determinants are responsible for different incidences of smear positive pulmonary tuberculosis (TB). The main determinants are cigarette smoking and diabetes mellitus. The aim of this study is to determine the effect of these risk factors effect modifiers in TB/gender association.

METHODOLOGY

In this retrospective cohort, relative risk of gender in developing smear positive TB as well as its interaction with smoking and diabetes mellitus were investigated.

RESULTS

Of 1243 smear positive TB cases, 63.2% were male. Prevalences of diabetes mellitus among men and women TB cases were 9.2% and 22.9% respectively (p<0.001). Frequency of cigarette smoking among men was significantly higher than that in women (61.7% vs. 7.6% respectively, p<0.001). Male gender, increased the risk of developing smear positive TB as of 98% and 5% in smokers and non-smokers respectively (p=0.001), indicating an interaction between gender and smoking in the effect on TB. In addition, male gender increased the risk of TB as of 13% and 34% in patients with and without diabetes mellitus respectively (p=0.300) indicating no interaction between gender and diabetes mellitus on TB incidence.

CONCLUSION

Our study showed that cigarette smoking is a determinant factor for gender differences in TB incidence but diabetes mellitus does not affect the association between TB and gender.

Comparative study of clinico-bacterio-radiological profile and treatment outcome of smokers and nonsmokers suffering from pulmonary tuberculosis

INTRODUCTION

Tuberculosis (TB) is one of the leading causes of death and disease worldwide. Tobacco smoking has been linked as a risk factor for TB. This study was aimed to affirm the strength of association between smoking and pulmonary TB.

MATERIALS AND METHODS

Pulmonary TB patients aged between 18 and 65 years were enrolled and followed-up until treatment completion. Two consecutive sputum smears were examined from each patient for the presence of acid-fast bacilli (AFB) using Ziehl-Neelsen technique. Radiological severity of disease was assessed using guidelines of National TB Association of USA. Sputum smears for AFB were graded for positivity as per WHO Revised National TB Control Programme criteria. Response was determined in terms of sputum conversion at the end of intensive phase and final treatment outcomes.

RESULTS

Sputum smear grading of 3+ increased from 12.5% to 68.18% and 66.66% as smoking index increased from <100 to 100-299 and >300 (P < 0.05). In nonsmokers, 79.2% patients had minimal disease while only 4.2% had advanced disease as compared to smokers where 52.4% had moderate disease, 26.2% advanced disease, and 21.4% minimal disease (P < 0.01). Smokers had significantly lower treatment success rate (69%) as against nonsmokers and former smokers (93.8% and 90.9%, respectively, P = 0.001) owing to a higher default rate among smokers (28.5%) than nonsmokers (6.3%) and former smokers (9.1%).

CONCLUSION

Smokers during initial presentation, as well as at end of the treatment demonstrate more radiological findings, cavitary disease, and worse sputum AFB smear grading. Smokers also have a poorer treatment success rate largely due to high percentage of default rate thus suggesting noncompliance as a main confounder to treatment success. Focus needs to be made to reduce defaulters which are more common among smokers.

Diabetes mellitus and its influence on sputum smear positivity at the 2nd month of treatment among pulmonary tuberculosis patients in Kuala Lumpur, Malaysia: A case control study

OBJECTIVE/BACKGROUND

Many studies have suggested that sputum smear conversion after 2 months of antituberculosis treatment is an important determinant of treatment success and can be a predictor for relapse. The objective of this study is to determine the factors that influence sputum smear conversion after 2 months of treatment among pulmonary tuberculosis patients receiving treatment in the Institute of Respiratory Medicine in Kuala Lumpur, Malaysia.

METHODS

A total of 75 cases and 75 controls were interviewed, and their medical records were retrieved in order to extract the information needed. All analyses were conducted using SPSS version 17, and binary logistic regression analysis was used to determine the predictors of sputum smear nonconversion.

RESULTS

Results showed that the following factors were associated with sputum smear positivity after 2 months of intensive treatment: diabetes mellitus (p=.013, odds ratio [OR]=2.59, 95% confidence interval [CI] 1.27-5.33), underweight body mass index (p=.025, OR=1.67, 95% CI 0.80-3.49), nonadherent to tuberculosis treatment (p=.024, OR=2.85, 95% CI 1.21-6.74), and previous history of tuberculosis (p=.043, OR=2.53, 95% CI 1.09-5.83). Multivariable analysis identified diabetes mellitus (p=.003, OR=4.01, 95% CI 1.61-9.96) as being independently associated with the risk of persistent sputum smear positivity after 2 months of intensive treatment.

CONCLUSION

Based on the findings, identification of these factors is valuable in strengthening the management and treatment of tuberculosis in Malaysia in the future. This study emphasizes the importance of diabetes screening and integration of diabetic controls among tuberculosis patients in achieving better treatment outcome.

Five-year assessment of time of sputum smears conversion and outcome and risk factors of tuberculosis patients in central iran

Objective. To evaluate risk factors which influence sputum smear conversion, outcome, and trends of conversion of sputum smear during 5 years and compare outcomes in patients with different regimens. Methods. In a retrospective cohort study, all patients with sputum smear positive tuberculosis were evaluated for comorbidities and demographic, microbiological, and therapeutic data and outcome. Smear examinations were performed at the beginning, at 2 months for CAT I, at 3 months for CAT II, at the end of second month of maintenance phase, and at the end of treatment. Results. This study enrolled 211 sputum smear positive patients, but 189 patients who completed the intensive phase of treatment were evaluated. Sputum smear of 158 patients converted at the end of intensive phase (83.6). Univariate analysis indicated that the risk of a persistent positive smear at the end of intensive phase was greater in diabetic patients ((odds 4.038, 95% CI 1.123-14.516) P = 0.033), and also a 3+bacillary load had risk of 2.933-fold ((95% CI 1.278-6.732) P = 0.011). Overall rate of unfavorable outcome was 20.9%. Factors associated with unfavorable outcome were age (P value 0.000), male gender (P value 0.027), diabetes (P value 0.000), and delayed conversion of sputum at the end of intensive phase (P value 0.000). Outcome for different regimens was not different significantly. Two specimens were isoniazid resistant. Conclusions. We suggest supervised treatment and care for diabetic patients and those with higher bacillary load. Paying attention to early diagnosis of tuberculosis in the elderly to reduce poor outcome and further measures to prevent transfer-out could improve the success rate.

[Pulmonary tuberculosis and tobacco: about 100 cases]

Le tabagisme et la tuberculose sont deux enjeux majeurs de santé publique au niveau mondial, en particulier dans les pays émergents. Pour déterminer les particularités cliniques, radiologiques, bactériologiques et thérapeutiques de la tuberculose pulmonaire chez les sujets tabagiques nous avons mené une étude prospective au service de phtisiologie de l'hôpital Moulay Youssef sur une période de 10 mois, portant sur 100 nouveaux cas de tuberculose pulmonaire, répartis en 2 groupes, 50 patients tabagiques: Groupe A et 50 patients non tabagiques: Groupe B. Tous nos patients étaient de sexe masculin, l’âge moyen était de 41 ans ± 12 chez le groupe A et de 36 ans ± 16 chez le groupe B. Le délai de consultation était plus long chez les tabagiques, la médiane était de 60j (30; 98) contre 40j (30; 60), la symptomatologie clinique était variable chez les deux groupes, dominée par les expectorations chez les tabagiques 96% contre 60%. Les lésions radiologiques étaient similaires chez les deux groupes ainsi que la charge bacillaire. Tous les patients ont été mis sous traitement antituberculeux. Après un mois du traitement, la Bacilloscopie était négative chez 50% du groupe A contre 66% chez le groupe B. la régression des lésions radiologiques était similaire chez les deux groupes. Le retard diagnostique et le retard de négativation des frottis sont les principales particularités de la tuberculose pulmonaire du sujet tabagique. Le sevrage tabagique doit faire partie intégrante de la prise en charge des patients atteints de tuberculose.

A comparison of tools used for tuberculosis diagnosis in resource-limited settings: a case study at Mubende referral hospital, Uganda

Background

This study compared TB diagnostic tools and estimated levels of misdiagnosis in a resource-limited setting. Furthermore, we estimated the diagnostic utility of three-TB-associated predictors in an algorithm with and without Direct Ziehl-Neelsen (DZM).

Materials and Methods

Data was obtained from a cross-sectional study in 2011 conducted at Mubende regional referral hospital in Uganda. An individual was included if they presented with a two weeks persistent cough and or lymphadenitis/abscess. 344 samples were analyzed on DZM in Mubende and compared to duplicates analyzed on direct fluorescent microscopy (DFM), growth on solid and liquid media at Makerere University. Clinical variables from a questionnaire and DZM were used to predict TB status in multivariable logistic and Cox proportional hazard models, while optimization and visualization was done with receiver operating characteristics curve and algorithm-charts in Stata, R and Lucid-Charts respectively.

Results

DZM had a sensitivity and specificity of 36.4% (95% CI = 24.9–49.1) and 97.1%(95% CI = 94.4–98.7) compared to DFM which had a sensitivity and specificity of 80.3%(95% CI = 68.7–89.1) and 97.1%(95% CI = 94.4–98.7) respectively. DZM false negative results were associated with patient’s HIV status, tobacco smoking and extra-pulmonary tuberculosis. One of the false negative cases was infected with multi drug resistant TB (MDR). The three-predictor screening algorithm with and without DZM classified 50% and 33% of the true cases respectively, while the adjusted algorithm with DZM classified 78% of the true cases.

Conclusion

The study supports the concern that using DZM alone risks missing majority of TB cases, in this case we found nearly 60%, of who one was an MDR case. Although adopting DFM would reduce this proportion to 19%, the use of a three-predictor screening algorithm together with DZM was almost as good as DFM alone. It’s utility is whoever subject to HIV screening all TB suspects.

Delayed culture conversion due to cigarette smoking in active pulmonary tuberculosis patients

Although many studies have assessed factors affecting culture conversion during tuberculosis treatment, few have looked into the effect of tobacco smoking. This study included 89 active pulmonary tuberculosis patients with positive sputum culture upon presentation and collected information regarding smoking history and culture conversion after 60 days of therapy. Current smokers had a higher risk (OR 5.6; 95%CI 1.7-18.7) of non-conversion after two months of therapy when compared to never and ex-smokers. Cavities on chest X-ray and alcohol abuse were shown to confound this association. After adjustment for cavities on the chest X-ray and alcohol abuse current smoking compared to current non-smoking remained significantly associated with culture non-conversion at 60 days of treatment (adjusted OR 6.9; 95%CI 1.8-26.7, p = 0.002) with a significant (p = 0.004) trend in adjusted OR with the number of cigarettes smoked daily to 11.6 (1.8-73.4) among those smoking more than 20 cigarettes per day. In conclusion tobacco smoking was found to delay culture conversion during treatment for pulmonary tuberculosis in a dose-dependent manner. More research is needed to elucidate the effects of smoking on tuberculosis treatment response, and of smoking cessation during tuberculosis treatment.

Smoking and 2-month culture conversion during anti-tuberculosis treatment

OBJECTIVE

To investigate risk factors for delayed sputum culture conversion to negative during anti-tuberculosis treatment, with an emphasis on smoking.

DESIGN

Nested case-control study of adults with non-cavitary, culture-confirmed pulmonary tuberculosis (TB) participating in an anti-tuberculosis treatment trial in Brazil. A case of delayed culture conversion was a patient who remained culture-positive after 2 months of treatment. Odds ratios with 95% confidence intervals were calculated.

RESULTS

Fifty-three cases and 240 control patients were analyzed. Smokers had three-fold greater odds of remaining culture-positive after 2 months of treatment (P = 0.007) than non-smokers, while smokers and ex-smokers who smoked >20 cigarettes a day had two-fold greater odds of remaining culture-positive after 2 months of treatment (P = 0.045).

CONCLUSION

Cigarette smoking adversely affects culture conversion during anti-tuberculosis treatment. Support for smoking cessation should be considered to improve outcomes in TB control programs.

Factors Influencing Sputum Conversion among Smear-Positive Pulmonary Tuberculosis Patients in Morocco

Background. Sputum smear-positive pulmonary tuberculosis patients expel infectious viable bacilli for a period following the commencement of treatment. Objective. To determine the time to sputum smear conversion and study the factors influencing it. Design. A prospective study was undertaken at our hospital in Rabat over a six-month period on a cohort of 119 sputum smear positive patients. Patients were followed up fortnightly. At each followup, specimens were collected and processed for microscopy using standard protocol. Results. 96.6% of our patients completed the study (4 deaths). Sputum conversion rate was 42% after two weeks, 73% after one month, and 95% after two months. Univariate and stepwise regression analysis showed that patients who had high smear grading, miliary, and bilateral radiologic lesions were more likely to undergo delayed sputum conversion (P<0.05). Other factors were thought to influence sputum conversion but were not statistically proven in our study. Conclusion. Since viable bacilli continue to be expelled for up to two months, infection control measures should be maintained for such a time. Patients with high smear grading, miliary, and bilateral radiologic lesions need to be monitored more closely.

Predictors of delayed sputum smear and culture conversion among a Portuguese population with pulmonary tuberculosis

INTRODUCTION

Failure of sputum smear and/or culture conversion after 2 months of tuberculosis (TB) treatment has been considered a predictor of patient infectivity and treatment failure. We aimed to identify the factors associated with delayed sputum smear and culture conversion in patients with pulmonary TB who were given anti-TB treatment.

MATERIAL AND METHODS

Retrospective cohort of 136 adult patients with sputum culture-proven pulmonary TB referred to an urban Chest Disease Centre. Socio-demographic, clinical, radiological, microbiological, and therapeutic data were evaluated.

RESULTS

The median age was 41.0 (interquartile range [IQR] 18.0) years and 75.0% of patients were male. Delayed sputum smear and culture conversion occurred in 25.4% (30/118) and 27.2% (37/136) of patients, respectively. Multivariate analysis indicated that age ≥ 50 years (odds ratio [OR] 4.4, 95% confidence interval [CI] 1.5-13.3), male gender (OR 10.8, 95% CI 1.3-91.1), and smear grade > 1-9 acid fast bacilli (AFB)/field (3+) (OR 11.7, 95% CI 1.4-100.6) were significantly associated with persistent smear positivity after 2 months of treatment. Bilateral radiological involvement (OR 3.7, 95% CI 1.5-9.0) and colony count > 100 (3+) (OR 5.8, 95% CI 1.2-27.4) were significantly associated with persistent culture positivity.

CONCLUSIONS

Delayed sputum smear and culture conversion occurred in about one third of patients. Older age, male gender, and higher bacillary load were independently associated with delayed smear conversion. Bilateral radiological involvement and higher colony count were independently associated with delayed culture conversion.

The SCIDOTS Project: evidence of benefits of an integrated tobacco cessation intervention in tuberculosis care on treatment outcomes

BACKGROUND

There is substantial evidence to support the association between tuberculosis (TB) and tobacco smoking and that the smoking-related immunological abnormalities in TB are reversible within six weeks of cessation. Therefore, connecting TB and tobacco cessation interventions may produce significant benefits and positively impact TB treatment outcomes. However, no study has extensively documented the evidence of benefits of such integration. SCIDOTS Project is a study from the context of a developing nation aimed to determine this.

METHODS

An integrated TB-tobacco intervention was provided by trained TB directly observed therapy short-course (DOTS) providers at five chest clinics in Malaysia. The study was a prospective non-randomized controlled intervention using quasi-experimental design. Using Transtheoretical Model approach, 120 eligible participants who were current smokers at the time of TB diagnosis were assigned to either of two treatment groups: conventional TB DOTS plus smoking cessation intervention (integrated intervention or SCIDOTS group) or conventional TB DOTS alone (comparison or DOTS group). At baseline, newly diagnosed TB patients considering quitting smoking within the next 30 days were placed in the integrated intervention group, while those who were contemplating quitting were assigned to the comparison group. Eleven sessions of individualized cognitive behavioral therapy with or without nicotine replacement therapy were provided to each participant in the integrated intervention group. The impacts of the novel approach on biochemically validated smoking cessation and TB treatment outcomes were measured periodically as appropriate.

RESULTS

A linear effect on both 7-day point prevalence abstinence and continuous abstinence was observed over time in the intervention group. At the end of 6 months, patients who received the integrated intervention had significantly higher rate of success in quitting smoking when compared with those who received the conventional TB treatment alone (77.5% vs. 8.7%; p < 0.001). Furthermore, at the end of TB treatment (6 months or later), there were significantly higher rates of treatment default (15.2% vs. 2.5%; p = 0.019) and treatment failure (6.5% vs. 0%; p = 0.019) in the DOTS group than in the SCIDOTS group.

CONCLUSION

This study provides evidence that connecting TB-tobacco treatment strategy is significant among TB patients who are smokers. The findings suggest that the integrated approach may be beneficial and confer advantages on short-term outcomes and possibly on future lung health of TB patients who quit smoking. This study may have important implications on health policy and clinical practice related to TB management among tobacco users.

Geographic differences in time to culture conversion in liquid media: Tuberculosis Trials Consortium study 28. Culture conversion is delayed in Africa

Background

Tuberculosis Trials Consortium Study 28, was a double blind, randomized, placebo-controlled, phase 2 clinical trial examining smear positive pulmonary Mycobacterium tuberculosis. Over the course of intensive phase therapy, patients from African sites had substantially delayed and lower rates of culture conversion to negative in liquid media compared to non-African patients. We explored potential explanations of this finding.

Methods

In TBTC Study 28, protocol-correct patients (n = 328) provided spot sputum specimens for M. tuberculosis culture in liquid media, at baseline and weeks 2, 4, 6 and 8 of study therapy. We compared sputum culture conversion for African and non-African patients stratified by four baseline measures of disease severity: AFB smear quantification, extent of disease on chest radiograph, cavity size and the number of days to detection of M. tuberculosis in liquid media using the Kaplan-Meier product-limit method. We evaluated specimen processing and culture procedures used at 29 study laboratories serving 27 sites.

Results

African TB patients had more extensive disease at enrollment than non-African patients. However, African patients with the least disease by the 4 measures of disease severity had conversion rates on liquid media that were substantially lower than conversion rates in non-African patients with the greatest extent of disease. HIV infection, smoking and diabetes did not explain delayed conversion in Africa. Some inter-site variation in laboratory processing and culture procedures within accepted practice for clinical diagnostic laboratories was found.

Conclusions

Compared with patients from non-African sites, African patients being treated for TB had delayed sputum culture conversion and lower sputum conversion rates in liquid media that were not explained by baseline severity of disease, HIV status, age, smoking, diabetes or race. Further investigation is warranted into whether modest variation in laboratory processes substantially influences the efficacy outcomes of phase 2 TB treatment trials or if other factors (e.g., nutrition, host response) are involved.

Trial Registration

ClinicalTrials.gov NCT00144417

Using System Dynamics tools to gain insight into intervention options related to the interaction between tobacco and tuberculosis

Tobacco exposure is an important risk factor for tuberculosis (TB) when considering its effects on population-level disease outcomes. If we hope to gain control over TB globally, we must begin to think ‘outside of the box’ to identify an extended and multi-faceted intervention strategy that is grounded in an understanding of the particular ways in which key risk factors worsen TB. In light of the role of tobacco exposure as an important, identifiable, modifiable, and preventable risk factor for TB, efforts aiming at reducing tobacco use merit inclusion in such a comprehensive TB control program. The goal of this paper is to share the conceptual framework we have developed using System Dynamics methodology, which diagrams the likely effects of tobacco exposure on TB dynamics in a typical low-income country setting. Using this framework as a guide, we leverage an understanding of the likely mechanisms by which tobacco exposure affects TB risk to systematically explore TB control intervention options. We hope that this paper will help inspire new approaches to extend and enhance traditional TB control efforts. We also hope that the conceptual framework will spark further discussion and research on this important and potentially explosive combination of global public health crises.

[Tobacco smoking and sputum smear conversion in pulmonary tuberculosis]

BACKGROUND AND OBJECTIVE

To analyze if cigarette smoking delays the sputum smear conversion in pulmonary tuberculosis.

PATIENTS AND METHOD

Ninety eight patients were diagnosed with pulmonary tuberculosis. Patients were all not immunosuppressed, infected by human immunodeficiecy virus (HIV) or drug resistant. Sixty four of them were smokers with a pack-year index (standard deviation) of 33.69 (23.12). Delayed sputum smear conversion (DC) was considered when 2 positive sputum culture results were obtained in the second month of anti-tuberculous treatment and was associated with the following variables in 2 groups: a) total group (in which all the patients were included): age, sex, smoking habits, risk factors (alcohol consumption, diabetes mellitus, immunosuppression, drug addicion, malnutrition), time with symptoms, radiologic presentation and bacterial load, and b) smokers: age, sex, risk factors, time with symptoms, radiologic presentation, bacterial load and pack-year index. For the statistical analysis, chi2 test, Student t test and logistic regression model were used, considering the dependant variable DC.

RESULTS

In the total group, 17 patients (17.3%) had DC, 16 of them had a history of smoking and in the univariate analysis it was associated with: alcohol consumption, time with symptoms, radiologic presentation as bilateral cavitary infiltrates and smoking habits. The logistic regression analysis showed an association with smoking habits (odds ratio = 9.8; p = 0.03) and bilateral cavitary infiltrates (odds ratio = 3.61; p = 0.02). In the group of smokers, DC was associated in the univariate analysis with the female sex.

CONCLUSIONS

Smoking habits delay sputum conversion in patients with pulmonary tuberculosis not associated with HIV and non-resistant bacilli. According to these results it is necessary to assist smoking cessation in patients who are receiving antituberculous treatment.

Effect of pharmacist-led patient education on adherence to tuberculosis treatment

PURPOSE

The purpose of this study was to assess the effect of a clinical pharmacist-directed patient education program on the therapy adherence of first-time tuberculosis (TB) patients and to identify the major pharmaceutical care needs and issues of first-time TB and multidrug-resistant (MDR)-TB patients.

METHODS

In the first part of the study, first-time TB patients were randomized either to the No EDU group (n = 58) where patients received routine medical and nursing care or to the EDU group (n = 56) where patients were also provided with clinical pharmacist-directed patient education. The patient's adherence to treatment was evaluated by attendance at scheduled visits, medication counting, and urine analysis for the presence of isoniazid metabolites. In the second part of the study, the pharmaceutical care needs and issues were determined for first-time TB patients and for MDR-TB patients (n = 40).

RESULTS

The adherence of patients who received pharmacist-directed patient education was greater than that of patients who did not. The attendance at scheduled visits and urine analysis for the presence of isoniazid metabolites yielded better results in respect to adherence for the EDU group (p < 0.05), while medication counting did not differ between the two groups. The major pharmaceutical care needs of first-time TB patients were for pain control, nutrient replacement, appropriate prescribing, respiratory control, and diabetic control. Similar findings were recorded for MDR-TB patients.

CONCLUSION

Patients' adherence to TB treatment improved when a pharmacist provided patient education on medication use and addressed patients' pharmaceutical care issues.