[Risk factors associated to tuberculosis patients with positive sputum microscopy]

CD4+ AND CD8+ T-CELLS EXPRESSING INTERFERON GAMMA IN ACTIVE PULMONARY TUBERCULOSIS PATIENTS

Background

Tuberculosis (TB) is a global health problem. Immune response through CD4⁺ and CD8⁺ T cells is needed to produce Interferon gamma (IFN-γ), a cytokine eliminate Mycobacterium tuberculosis. We aimed to compare the cellular immune response based on the percentage of CD4⁺ and CD8⁺ T cells expressing interferon gamma in active pulmonary tuberculosis patients before and after 2 months of tuberculosis treatment.

Methods

It is a longitudinal cohort study included 12 patients with new active pulmonary TB of the Pulmonary Hospital, Surabaya. The CD4⁺ and CD8⁺ T cells expressing interferon gamma was measured by flow cytometry method.

Results

The mean CD4⁺ interferon gamma percentage of new active pulmonary TB before treatment was higher than 2 months after tuberculosis treatment (4.48% vs. 1.52%) and there was a significantly decreased (p = 0.025). The mean CD8⁺ interferon gamma percentage of new active pulmonary TB before treatment was higher than 2 months after tuberculosis treatment (3.56% vs. 2.89%) but not significantly decreased (p = 0.186).

Conclusions

The mean CD4⁺ IFN-γ percentage of new active pulmonary TB before treatment was higher than 2 months after treatment, suggesting that CD4⁺ T cells expressing IFN-γ play a role in protection against pulmonary TB infection.

Prevalence of chest symptoms amongst brick kiln migrant workers and care seeking behaviour: a study from South India

BACKGROUND

Early detection and treatment of tuberculosis (TB) have been key principles of TB control. However, this can be a challenge with 'hard to reach' populations such as migrants. Brick kiln workers are one such group of migrants who are exposed to smoke, heat and dust from brick kilns which are one of the major causes of respiratory illnesses.

METHODOLOGY

A cross-sectional community based study was carried out in Thiruvallur, Tamil Nadu, South India, from August 2011 to June 2012. A total of 4002 individuals from 55 brick kiln chambers were interviewed to determine the prevalence of chest symptoms and care seeking behaviour patterns.

RESULTS

Three hundred and seventy-seven (9.4%) chest symptomatics were identified. The most significant variables associated with chest symptoms were illiteracy, alcohol abuse and heavy smoking. Of the chest symptomatics identified, 50.4% took action to get relief from their symptoms. The duration of over 6-month stay in the chamber was significantly associated with taking action (OR, 5.5, 95% CI: 2.3, 13.3).

CONCLUSIONS

The TB control programme needs to further explore how to extend its services to such 'hard to reach' groups. Active case finding to ensure early diagnosis and treatment initiation amongst such groups needs consideration.

Public transportation and pulmonary tuberculosis, Lima, Peru

The association between public transportation for commuting and pulmonary tuberculosis (TB) was analyzed in workers in Lima, Peru. Traveling in minibuses was a risk factor for pulmonary TB. Preventive measures need to be taken by health services to prevent spread of this disease.

Gender differentials of pulmonary tuberculosis transmission and reactivation in an endemic area

BACKGROUND

In most low income countries there are twice as many cases of tuberculosis (TB) reported among men than among women, a difference commonly attributed to biological and epidemiological characteristics as well as socioeconomic and cultural barriers in access to health care. The World Health Organization has encouraged gender specific comparisons in TB rates to determine whether women with TB are less likely than men with TB to be diagnosed, reported, and treated. A study was undertaken to identify gender based differences in patients with pulmonary TB and to use this information to improve TB control efforts.

METHODS

Individuals with a cough for more than 2 weeks in southern Mexico were screened from March 1995 to April 2003. Clinical and mycobacteriological information (isolation, identification, drug susceptibility testing and IS6110 based genotyping, and spoligotyping) was collected from those with bacteriologically confirmed pulmonary TB. Patients were treated in accordance with official norms and followed to ascertain treatment outcome, retreatment, and vital status.

RESULTS

623 patients with pulmonary TB were enrolled. The male:female incidence rate ratio for overall, reactivated, and recently transmitted disease was 1.58 (95% CI 1.34 to 1.86), 1.64 (95% CI 1.36 to 1.98), and 1.41 (95% CI 1.01 to 1.96), respectively. Men were more likely than women to default from treatment (adjusted OR 3.30, 95% CI 1.46 to 7.43), to be retreated (hazard ratio (HR) 3.15, 95% CI 1.38 to 7.22), and to die from TB (HR 2.23, 95% CI 1.25 to 3.99).

CONCLUSIONS

Higher rates of transmitted and reactivated disease and poorer treatment outcomes among men are indicators of gender differentials in the diagnosis and treatment of pulmonary TB, and suggest specific strategies in endemic settings.

[Social risk factors for noncompliance with tuberculosis treatment in Pontevedra [Spain]]

OBJECTIVE

To determine the prevalence and characteristics of social risk factors (SRF) for noncompliance with treatment in patients with tuberculosis (TB) in Pontevedra.

METHODS

We performed a descriptive analysis of patients with TB and SRF diagnosed between 1996 and 2002. A patient was considered as having SRF if he or she was socially isolated (alcoholism, intravenous drug use, prison inmate, homelessness or social maladjustment) or was an immigrant. The prevalence, annual trend of SRF and patient outcomes were calculated. The influence of direct observation of treatment administration on the outcome of patients with SRF was also analyzed.

RESULTS

Of 775 patients with TB, 156 (20.1%) had at least one SRF. Eighty-six patients were alcoholic, 41 were intravenous drug users, 24 were immigrants, 11 were homeless, 11 showed social maladjustment and 10 were prison inmates. The presence of SRF among TB patients showed no tendency to increase or decrease during the study period, except for the increasing number of immigrants (chi 2 for lineal tendency = 12.24; p = 0.005). Final outcomes were significantly better in patients without SRF (90.4 vs 70.8% of satisfactory final outcomes; p < 0.001). Direct observation of treatment did not increase satisfactory outcomes in patients with SRF.

CONCLUSIONS

Patients with TB and SRF have a significantly higher proportion of unsatisfactory final outcomes. The presence of SRF is relatively low in our environment. The number of immigrants from countries with a high prevalence of TB shows an incipient tendency to increase. This finding should be taken into account to achieve better control of the disease.

[Analysis of six families with microepidemics detected in the tuberculosis contact tracing]

BACKGROUND AND OBJECTIVE

The aim of the present study was to analyze the characteristics of families with microepidemics of tuberculosis.

PATIENTS AND METHOD

We included family studies examined in the Center for Tuberculosis Control and Prevention of Lleida during the period 1991-97. A microepidemic was defined as the appearance of two or more new cases in the same family study. The association between the detection of new cases among family contacts and the prevalence of tuberculosis infection was analyzed.

RESULTS

Prevalence of families with microepidemics was 1.4% (6/437). Families with microepidemics generated 15 out of 39 newly diagnosed cases (38.5%). We observed a higher prevalence of tuberculosis infection in families with one new case (OR = 1.67; CI 95%, 1.19-2.34) and in families with microepidemics (OR = 2.67; CI 95%, 1.28-5.62).

CONCLUSIONS

Study of microepidemics of tuberculosis is very important because a small percentage of families with microepidemics (1.4%) generate a large number of secondary cases who are diagnosed during the screening of tuberculosis contacts (38.5%).