A spatial analysis of TB cases and abnormal X-rays detected through active case-finding in Karachi, Pakistan.

Tuberculosis (TB) is the leading cause of avoidable deaths from an infectious disease globally and a large of number of people who develop TB each year remain undiagnosed. Active case-finding has been recommended by the World Health Organization to bridge the case-detection gap for TB in high burden countries. However, concerns remain regarding their yield and cost-effectiveness. Data from mobile chest X-ray (CXR) supported active case-finding community camps conducted in Karachi, Pakistan from July 2018 to March 2020 was retrospectively analyzed. Frequency analysis was carried out at the camp-level and outcomes of interest for the spatial analyses were mycobacterium TB positivity (MTB+) and X-ray abnormality rates. The Global Moran's I statistic was used to test for spatial autocorrelation for MTB+ and abnormal X-rays within Union Councils (UCs) in Karachi. A total of 1161 (78.1%) camps yielded no MTB+ cases, 246 (16.5%) camps yielded 1 MTB+, 52 (3.5%) camps yielded 2 MTB+ and 27 (1.8%) yielded 3 or more MTB+. A total of 79 (5.3%) camps accounted for 193 (44.0%) of MTB+ cases detected. Statistically significant clustering for MTB positivity (Global Moran's I: 0.09) and abnormal chest X-rays (Global Moran's I: 0.36) rates was identified within UCs in Karachi. Clustering of UCs with high MTB positivity were identified in Karachi West district. Statistically significant spatial variation was identified in yield of bacteriologically positive TB cases and in abnormal CXR through active case-finding in Karachi. Cost-effectiveness of active case-finding programs can be improved by identifying and focusing interventions in hotspots and avoiding locations with no known TB cases reported through routine surveillance.

Status of Tuberculosis services in Indian Prisons.

INTRODUCTION: Prisons are known to be a high risk environment for tuberculosis (TB) due to overcrowding, low levels of nutrition, poor infection control and lack of accessible healthcare services. India has nearly 1400 prisons housing 0.37 million inmates. However, information on, availability of diagnostic and treatment services for TB in the prison settings is limited. This study examined the availability of TB services in prisons of India. Simultaneously, prison inmates were screened for tuberculosis. METHOD: The study was conducted in 157 prisons across 300 districts between July-December 2013. Information on services available and practices followed for screening, diagnosis and treatment of TB was collected. Additionally, the inmates and prison staff were sensitised on TB using interpersonal communication materials. The inmates were screened for cough ≥2 weeks as a symptom of TB. Those identified as presumptive TB patients (PTBP) were linked with free diagnostic and treatment services. RESULTS: Diagnostic and treatment services for TB were available in 18% and 54% of the prisons respectively. Only half of the prisons screened inmates for TB on entry, while nearly 60% practised periodic screening of inmates. District level prisons (OR, 6.0; 95% CI, 1.6-22.1), prisons with more than 500 inmates (OR, 52; 95% CI, 1.4-19.2), and prisons practising periodic screening of inmates (OR, 2.7; 95% CI, 1.0-7.2) were more likely to diagnose TB cases. 19% of the inmates screened had symptoms of TB (cough ≥2 weeks) and 8% of the PTBP were diagnosed with TB on smear microscopy. CONCLUSION: The TB screening, diagnostic and treatment services are sub-optimal in prisons in India and need to be strengthened urgently.

UTILITY OF ROUTINE CHEST RADIOGRAPHS IN KENYA.

BACKGROUND: Many otherwise healthy Kenyans are required to obtain chest radiographs as part of routine medical examination to exclude pulmonary TB, a condition of significant public health concern. Many of these people are required to have these radiographs taken yearly as part of routine check-up. No local data is available to support this practice. Though a quick procedure to perform and readily available throughout the country, chest radiograph exposes the individual to a dose of ionising radiation. Ionising radiation is associated with increased risk of malignancy. The cost is also substantial. OBJECTIVE: To determine the prevalence of radiological findings consistent with PTB among routine medical examination chest radiographs. DESIGN: A cross-sectional descriptive study. SETTINGS: Department of Radiology Kenyatta National Hospital, Department of Imaging and Radiation Medicine, University of Nairobi, Plaza Imaging Solutions, a private radiology practice in Nairobi and Department of Radiology, the Nairobi Hospital. SUBJECTS: Four hundred and two chest radiographs of patients presenting for routine medical examinations were analysed. RESULTS: Sixty three radiographs had abnormal but clinically insignificant findings (16%). Only one radiograph (0.25%) had radiological features of PTB. The rest were reported as normal (84%). CONCLUSION: In this study, the diagnostic yield for the intended purpose (to include/ exclude PTB) was extremely low (0.25%). It is recommended that routine chest radiographs as screening tools for active pulmonary tuberculosis be reconsidered due to poor diagnostic yield. The authors propose a bigger nation wide study before a policy decision can be proposed.

Tuberculosis screening of travelers to higher-incidence countries: a cost-effectiveness analysis.

BACKGROUND: Travelers to countries with high tuberculosis incidence can acquire infection during travel. We sought to compare four screening interventions for travelers from low-incidence countries, who visit countries with varying tuberculosis incidence. METHODS: Decision analysis model: We considered hypothetical cohorts of 1,000 travelers, 21 years old, visiting Mexico, the Dominican Republic, or Haiti for three months. Travelers departed from and returned to the United States or Canada; they were born in the United States, Canada, or the destination countries. The time horizon was 20 years, with 3% annual discounting of future costs and outcomes. The analysis was conducted from the health care system perspective. Screening involved tuberculin skin testing (post-travel in three strategies, with baseline pre-travel tests in two), or chest radiography post-travel (one strategy). Returning travelers with tuberculin conversion (one strategy) or other evidence of latent tuberculosis (three strategies) were offered treatment. The main outcome was cost (in 2005 US dollars) per tuberculosis case prevented. RESULTS: For all travelers, a single post-trip tuberculin test was most cost-effective. The associated cost estimate per case prevented ranged from $21,406 for Haitian-born travelers to Haiti, to $161,196 for US-born travelers to Mexico. In all sensitivity analyses, the single post-trip tuberculin test remained most cost-effective. For US-born travelers to Haiti, this strategy was associated with cost savings for trips over 22 months. Screening was more cost-effective with increasing trip duration and infection risk, and less so with poorer treatment adherence. CONCLUSION: A single post-trip tuberculin skin test was the most cost-effective strategy considered, for travelers from the United States or Canada. The analysis did not evaluate the use of interferon-gamma release assays, which would be most relevant for travelers who received BCG vaccination after infancy, as in many European countries. Screening decisions should reflect duration of travel, tuberculosis incidence, and commitment to treat latent infection.

Screening of new entrants for tuberculosis: responses to port notifications.

BACKGROUND: Tuberculosis in England and Wales is associated with recently arrived immigrants. Screening new entrants for tuberculosis has received considerable attention recently. Despite several calls to reorganize screening processes for new entrants because of perceived ineffectiveness, some systems at ports have remained largely unchanged, including notification arrangements. METHODS: A postal questionnaire was sent to Consultants in Communicable Disease Control (CsCDC) who normally receive port health notification forms from London Heathrow Port Health Control Unit relating to new entrants who had either been screened and found to have a normal chest X-ray, not had an chest X-ray due to pregnancy or young age or whose examination was inconclusive (Port 101 and 102 forms). RESULTS: Almost half of the responding CsCDC attempted to follow-up all Port 101 and 102 referrals; of these CsCDC, 46 percent reported that they were actually able to follow-up under 50 percent. CsCDC had developed their own criteria to aid decisions as to which referrals to follow-up. CONCLUSION: The follow-up by CsCDC of new entrants passing through Heathrow Port Health Control Unit who have been screened and found to have a normal chest X-ray, not had an X-ray due to pregnancy or young age, or whose examination was inconclusive varies considerably and there is no consistent national practice. Substantial efforts are being expended on attempting to follow-up new entrants, many of whom may be at low risk of tuberculosis. The effectiveness (and efficiency) of this approach is probably low.

[Industrial production of the LDRD "Siberia-N" digital radiographic devices]. / Promyshlennoe proizvodstvo tsifrovykh fliuorograficheskikh apparatov MTsRU "Sibir'-N".

It is envisaged, as a key task, in the Federal Program on Tuberculosis Monitoring, that preventive measures and early TB detection is a priority. Fluorography, which is important for the recognition of pulmonary tuberculosis at its early stages, has been used in the diagnostics of pulmonary pathologies. However, according to the statistics provided by the Russian Ministry of Healthcare, around 80% of available medical equipment is now worn and obsolete. Owing to a fruitful research activity related with designing a digital low-dose X-Ray unit (Siberia-N) carried out by the Budker Institute of Nuclear Physics, Siberian Branch of the Russian Academy of Sciences (Novosibirsk), a certain progress can be stated in perfecting the fluorography equipment in Russia. The above unit incorporates all advanced achievements in the field of digital X-Ray diagnostics.

Assessment of tuberculosis screening and management practices of large jail systems.

OBJECTIVE: This descriptive study sought to explore the use and timeliness of tuberculosis (TB) screening and management activities in jail facilities. METHODS: Study personnel visited 20 large U.S. jail systems and reviewed the medical records of 56 inmates who had recently been evaluated for TB disease and 376 inmates who were diagnosed with or confirmed to have latent TB infection (LTBI). Data from these records were analyzed to determine completion and timeliness of screening, diagnostic, and treatment activities. RESULTS: In 14% of 56 inmates evaluated for TB disease and 24% of 376 inmates with LTBI, chest radiographs were either not performed or not documented. Of 48 inmates evaluated for TB disease who were not receiving treatment when admitted to jail, 10 had no record of sputum collection being done. A mean delay of 3.1 days occurred from symptom report to respiratory isolation. Time from tuberculin skin test reading to chest radiograph reading was a mean of 5.3 days in inmates evaluated for TB disease and a mean of 7.0 days in inmates with LTBI. Follow-up was arranged for 91% of released inmates who were on treatment for TB disease and only 17% of released inmates who were on treatment for LTBI. CONCLUSIONS: Jail health information systems should be augmented to better document and monitor inmate health care related to TB. Completion rates and timeliness of TB screening, diagnostic, and treatment measures should be evaluated to identify areas needing improvement. Finally, mechanisms for continuity of care upon inmate release should be enhanced to promote therapy completion and prevent TB transmission in the community.

Time from finding abnormality on mass-screening to final diagnosis of lung cancer.

Mass-screening for lung cancer is rather a unique system in Japan. This study illustrates time from finding abnormality on mass-screening to final diagnosis of lung cancer. Among the 517 patients with lung cancer who were admitted to our hospital over a 10-year period up to December 2001, 83 (16.1%) were detected by mass-screening. We reviewed medical records of the 83 patients and determined the intervals from the mass-screening to the pathological diagnosis with clinical staging. Time from the mass-screening to the date of hospital visit was <2 months in 62 (74.7%) cases. Five (6.0%) patients visited hospital more than 6 months after the mass-screening. With respect to the interval, there was no statistical difference in gender (p=0.0680) and age (p=0.1532). Among 60 patients who were referred from outside, on average, patients visited our hospital 0.5 month after they first sought medical attention at nearby clinic, and at our hospital 0.5 month was required to make a pathological diagnosis of lung cancer with TNM staging. There was a statistical difference in survival between the patients who were diagnosed <4 months and the patients who were diagnosed >4 months from the screening (p=0.0487). The interval in most cases was acceptable. However, further improvements are still needed to minimize the delay and to maximize the benefits of early cancer detection.

Outcome in patients with lung cancer found on lung cancer mass screening roentgenograms, but who did not subsequently consult a doctor.

GOALS OF THE STUDY: To evaluate the outcome in patients with lung cancer found on lung cancer mass screening roentgenograms, but who did not subsequently consult a doctor. PATIENTS AND METHODS: This study enrolled 198 asymptomatic patients with lung cancer found by lung cancer mass screening during the 9-year period. Five-year survival rates in patients who did not consult a doctor or who stopped consulting a doctor in spite of abnormal shadows detected on last mass screening chest roentgenograms (n=45, delayed consultation group) and in patients who subsequently consulted a doctor when abnormal shadows were detected (n=153, control group) were evaluated by the method of Kaplan and Meier and clinical variables were examined as possible predictors of survival time by the Cox proportional-hazards model. RESULTS: There was a significant difference between the 5-year survival rates in the delayed consultation group and in the control group (21 vs. 51%, log rank: P=0.0003, Wilcoxon: P=0.0009). The risk of death increased 115.0% for the 1-year delay in consultation (hazard ratio: 2.150, 95% CI: 1.203-3.842, P=0.0097). With regard to the reason why they did not consult a doctor, many of them answered that they did not have any respiratory symptoms. CONCLUSION: The 1-year delay in consultation had a great significance in that these patients did not receive any treatment for lung cancer for 1 year, and the 1-year delay in treatment itself affected the outcome.

Are routine chest X-rays for students entering university worthwhile?

Mass radiographic screening for tuberculosis has lost favour in many countries. The aim of this study was to determine whether the continued practice of such screening of prospective students at the University of the West Indies was warranted by assessing the yield and the cost of the programme in our setting. In a cross- sectional retrospective study, 12,662 chest X-ray reports collected over the period 1989-1997 were studied. No active case of tuberculosis was detected. Three students reported a previous history of tuberculosis and 10 students had a positive family history of tuberculosis. Three hundred and ninety-nine clinically insignificant abnormalities were reported, such as mild scoliosis and calcified foci. Routine radiological screening of prospective students at the University of the West Indies for tuberculosis has an extremely low yield, places the students at unnecessary risk of radiation exposure and should be discontinued.

Survey of physician use of radiography and sputum smear microscopy for tuberculosis diagnosis and follow-up in Botswana.

SETTING: National survey of physician knowledge, attitudes, and practices for tuberculosis (TB) diagnosis and monitoring in Botswana. OBJECTIVE: To assess adherence to national guidelines for TB diagnosis and monitoring. DESIGN: Questionnaires were mailed to all physicians registered with the Ministry of Health. RESULTS: The response rate was 69%. Diagnostic and follow-up practices differed substantially from national recommendations. Senior District Medical Officers (SDMOs) were the most likely to adhere to guidelines on use of sputum examination for diagnosis (87%) and follow-up (50%); private practitioners were the least likely to follow the same guidelines (53% and 10%, respectively). SDMOs were also less likely to use radiographs for diagnosis (27%); the greatest use was seen in government hospital-based physicians (86%). While most SDMOs had received an introduction to the TB programme and had access to the programme manual and recent information on TB, the majority of other practising physicians in the country did not. CONCLUSION: Recommended diagnostic procedures for TB were not being followed by a substantial percentage of physicians. Efforts are being made to inform hospital-based physicians and private practitioners about TB programme policies. Adherence to programme recommendations is vital to strengthen TB control efforts.

Control of tuberculosis in health service workers: the role of the chest radiograph.

Chest radiograph reports were reviewed retrospectively in 1994 new employees in the Leicestershire Health Authority to assess the use of this examination in detecting and preventing tuberculosis. No evidence suggestive of active tuberculosis was found in the cases reviewed indicating that the chest radiograph is of limited value. A discussion of these findings and a review of previous work suggests that a change in screening policy with the pre-employment chest radiograph performed only on selected groups would have no significant effect on the incidence of tuberculosis in staff or patients. The savings both in radiation exposure and financially would be considerable.

Use and effectiveness of chest radiography and low-back radiography in screening.

One of the Food and Drug Administration's educational programs to optimize the use of medical radiation is the investigation of the efficacy of selected x-ray film examinations. The goal of this program is to provide clinical information needed to aid physicians in their judgment. The routine chest-radiograph screening examination has been studied, and recommendations for five applications of chest-radiograph screening have been published. These recommendations, plus results of FDA research on the efficacy of low-back radiography, are discussed.