Comparison of Tuberculin Reaction Sizes at 48 and 72 hours among children in Tiruvallur District, South India

Setting: A rural population in Tiruvallur district, south India. Objective: To study the variability of skin test reaction sizes between 48 and 72 hours. Methods: A tuberculin test survey was conducted among children aged less than 10 years. The reaction sizes were read by the same reader at 48 hours and 72 hours independently. The results of the tuberculin test were compared. Results: Of 957 children aged below 10 years were included in the study; the male and female ratio was 1:1.1. There were no significant differences between the readings of reaction size at 48 and 72 hours. Conclusion: The tuberculin test results can be read either at 48 hours or 72 hours without compromising the validity

Estimation of annual risk of tuberculosis infection among children irrespective of BCG scar in the south zone of India

Objective: To estimate the proportion infected and compute Annual Risk of Tuberculosis Infection (ARTI) among children irrespective of BCG scar and compare with that among children without BCG scar. Methodology: Tuberculin survey was conducted in south zone of India as a part of the nation-wide survey to estimate the ARTI in different parts of the country and ARTI was computed among children without BCG scar excluding children with BCG scar. In this exercise, the tuberculin test results of children with BCG scar and irrespective of BCG scar were considered for analysis and the results were compared. Results: The prevalence of infection and ARTI estimated among children irrespective of BCG scar aged 1-9 years were 5.7% and 1.0% (95% C.I: 0.8-1.3) respectively. The corresponding figures among unvaccinated children were 5.9% and 1.0% (95% C.I: 0.7-1.4) respectively. The ARTI among children irrespective of BCG scar were similar to that among unvaccinated children. Conclusion: Estimation of proportion of children infected and computation of ARTI using mirror-image technique could be undertaken among children irrespective of BCG scar among children aged either from 1-9 years or 5-9 years

Repeatability of nerve thickness assessment in the clinical examination for leprosy

The assessment of the thickness of the superficial peripheral nerve trunks to document nerve involvement is an important aspect of clinical examination in case finding for leprosy, and is usually done by trained paramedical workers (PMWs). This assessment is subject to variability and has implications on the outcome of the survey. The present study proposes to quantify this variability. In this study, 242 individuals, consisting of 50 neuritic cases, 143 nonneuritic cases of leprosy and 49 normal controls, selected from the records of the trial of BCG prophylaxis in leprosy in South India, were examined by a doctor and paramedical workers. Repeatability of nerve thickness assessment for ulnar aud popliteal nerves between the medical officer (MO) and the PMWs was quantified using Kappa statistics. The Kappa values for repeatability between the MO and the PMWs ranged from 0.45 to 0.54 and 0.52 to 0.69 for ulnar and popliteal nerves, respectively. The implications of the variability in nerve assessment are discussed

Estimation of burden of tuberculosis in India for the year 2000

Background & objectives: Data on the burden of tuberculosis (TB) in India are vital for programme planners to plan the resource requirements and for monitoring the nation-wide TB control programme. There was a need to revise the earlier estimate on the burden of TB in India based on the increase in population and current epidemiological data. This study estimates the burden of disease for the year 2000 based on recent prevalence of TB and annual risk of tuberculosis infection (ARTI) estimates. Methods: Data on prevalence generated among adults by the Tuberculosis Research Centre (TRC), Chennai, among children by National Tuberculosis Institute (NTI), Bangalore, and the ARTI estimates from the nation-wide sample survey by NTI and TRC were used for the estimation. The prevalence of disease corresponding to 1 per cent ARTI was extrapolated to different parts of the country using the estimates of ARTI and the population in those areas and added together to get the total cases. Abacillary cases that required treatment were estimated from X-ray abnormals. The estimates of bacillary, abacillary and extrapulmonary cases were then combined to get the national burden. Results: The estimated number of bacillary cases was 3.8 million (95% CI: 2.8 - 4.7). The number of abacillary cases was estimated to be 3.9 million and that for extrapulmonary cases was 0.8 million giving a total burden of 8.5 million (95% CI: 6.3-10.4) for 2000. Interpretation & conclusion: The present estimate differs from the earlier estimates because we have included the disease burden of X-ray cases that are likely to breakdown to bacillary cases in a one year period, and extrapulmonary TB cases. The current estimates provided baseline information for advocacy and planning resource allocation for TB control activities. Also, these estimates can be compared with that in future years to measure the long term impact of TB control activities in India

The timing of death in patients with tuberculosis who die during anti-tuberculosis treatment in Andhra Pradesh, South India

Background: India has 2.0 million estimated tuberculosis (TB) cases per annum with an estimated 280,000 TBrelated deaths per year. Understanding when in the course of TB treatment patients die is important for determining the type of intervention to be offered and crucially when this intervention should be given. The objectives of the current study were to determine in a large cohort of TB patients in India:- i) treatment outcomes including the number who died while on treatment, ii) the month of death and iii) characteristics associated with “early” death, occurring in the initial 8 weeks of treatment. Methods: This was a retrospective study in 16 selected Designated Microscopy Centres (DMCs) in Hyderabad, Krishna and Adilabad districts of Andhra Pradesh, South India. A review was performed of treatment cards and medical records of all TB patients (adults and children) registered and placed on standardized anti-tuberculosis treatment from January 2005 to September 2009. Results: There were 8,240 TB patients (5183 males) of whom 492 (6%) were known to have died during treatment. Case-fatality was higher in those previously treated (12%) and lower in those with extra-pulmonary TB (2%). There was an even distribution of deaths during anti-tuberculosis treatment, with 28% of all patients dying in the first 8 weeks of treatment. Increasing age and new as compared to recurrent TB disease were significantly associated with “early death”. Conclusion: In this large cohort of TB patients, deaths occurred with an even frequency throughout anti-TB treatment. Reasons may relate to i) the treatment of the disease itself, raising concerns about drug adherence, quality of anti-tuberculosis drugs or the presence of undetected drug resistance and ii) co-morbidities, such as HIV/ AIDS and diabetes mellitus, which are known to influence mortality. More research in this area from prospective and retrospective studies is needed

Trends in the prevalence of pulmonary tuberculosis over a period of seven and half years in a rural community in south India with DOTS.

SETTING Tiruvallur district In Tamil Nadu where DOTS was implemented by the State Government as the tuberculosis control measure in 1999, and monitored by the National Institute for Research in Tuberculosis for over five years. OBJECTIVE To estimate trends in TB prevalence in a rural community with DOTS. DESIGN Surveys of pulmonary tuberculosis were undertaken in representative samples of subjects aged > or =15 years (N = 83,000 - 92,000), initially and after two and half, five and seven and half years of implementation of DOTS. Sputa were collected from those with abnormal radiograph and/or presence of chest symptoms, and examined by direct smear and culture. RESULTS The prevalence of culture-positive tuberculosis was 607, 454, 309 and 388 per 100,000 in the four surveys, and that of smear-positive tuberculosis was 326, 259, 168 and 180. In the first five years; annual decrease was 12.4% (95% CI 10.4 - 14.4%) for culture-positive tuberculosis, and 12.2% (95% CI 8.0-16.2) for smear-positive tuberculosis. This was, however, followed by a significant increase in the next two and half years. The average new smear-positive case-notification rate was 75 per 100,000 during first four years but declined to 49 in subsequent years. There were no methodological differences during this period and information on changes in socio-economic indicators and nutritional standards was unavailable. CONCLUSION Despite the average annual success rate (78%) in this tuberculosis unit being lower than the expected rate of 85%, the implementation of DOTS was followed by a substantial decrease in the prevalence of pulmonary tuberculosis over the seven and half year period. Our findings suggest that sustaining the high effectiveness of DOTS programme needs vigilant supervision

Risk factors for pulmonary tuberculosis: a clinic-based case control study in The Gambia

BACKGROUND: The tuberculosis (TB) epidemic in Africa is on the rise, even in low-HIV prevalence settings. Few studies have attempted to identify possible reasons for this. We aimed to identify risk factors for pulmonary tuberculosis in those attending a general outpatients clinic in The Gambia, a sub-Saharan African country with relatively low HIV prevalence in the community and in TB patients. METHODS: We conducted a case control study at the Medical Research Council Outpatients' clinic in The Gambia. Pulmonary TB cases were at least 15 years old, controls were age and sex matched clinic attendees. Participants were interviewed using a structured questionnaire. RESULTS: 100 sputum smear positive TB cases and 200 clinic controls were recruited. HIV prevalence was 6.1% in cases and 3.3% in controls. Multivariable assessment of host factors showed that risk of TB was increased among the Jola ethnic group and smokers, and decreased in those in a professional occupation. Assessment of environmental factors showed an increased risk with household crowding, history of household exposure to a known TB case, and absence of a ceiling in the house. In a combined multivariable host-environment model, the risk of TB increased with crowding, exposure to a known TB case, as well as amongst the Jola ethnic group. CONCLUSION: In The Gambia, household crowding and past household exposure to a known TB case are the standout risk factors for TB disease. Further research is needed to identify why risk of TB seems to differ according to ethnicity

The impact of smoking on adherence to treatment for latent tuberculosis infection

BACKGROUND: Studies have shown an association between smoking and tuberculosis (TB) infection, disease and TB-related mortality. We hypothesized that smokers with latent tuberculosis infection (LTBI) are less likely to comply with their LTBI treatment regimen, thus increasing their risk of developing active disease. We thus documented the impact of smoking on adherence to LTBI treatment. METHOD: Between 1998 and 2000, a convenience sample of patients undergoing treatment for LTBI completed a questionnaire on smoking status. Level of adherence to LTBI treatment was tested for associations with socio-demographic profile, and smoking status RESULTS: 320 patients were recruited, and 302 (94%) completed the questionnaire. Smoking prevalence was 21%. 72% of patients were adherent to LTBI treatment. Women (OR = 2.0; 95% CI: 1.2–3.3) and non-smokers (OR = 1.8; 95% CI: 1.0–3.3) were associated with adherence to LTBI treatment. Only gender was found as an independent predictor of adherence after adjusting for age and smoking status (OR = 1.9; 95% CI: 1.06–3.3). CONCLUSION: Males and smokers need to have extra supervision to ensure compliance with LTBI treatment

Deaths among tuberculosis cases in Shanghai, China: who is at risk?

<p>Abstract</p> <p>Background</p> <p>Information about the risk factors associated with death caused by tuberculosis (TB) or death with TB would allow improvements in the clinical care of TB patients and save lives. The present study sought to identify characteristics associated with increased risk of death during anti-TB treatment in Shanghai, a city in China with one of the country's highest TB mortality rates.</p> <p>Methods</p> <p>We evaluated deaths among culture positive pulmonary TB cases that were diagnosed in Shanghai during 2000–2004 and initiated anti-TB therapy. Demographic, clinical, mycobacteriological information and treatment outcomes were routinely collected through a mandatory reporting system.</p> <p>Results</p> <p>There were 7,999 culture positive pulmonary cases reported during the study period. The overall case fatality rate was 5.5% (440 cases), and approximately half (50.5%) of the deaths were attributed to causes other than TB. Eighty-six percent of the deaths were among TB cases age ≥ 60 years. The significant independent risk factors for mortality during anti-TB treatment were advancing age, male sex, sputum smear positivity, and the presence of a comorbidity.</p> <p>Conclusion</p> <p>More vigorous clinical management and prevention strategies by both the TB control program and other public health programs are essential to improve TB treatment outcomes. Earlier suspicion, diagnosis and treatment of TB, especially among persons older than 60 years of age and those with a comorbid condition, could reduce deaths among TB patients.</p