Cumulative Incidence Of Tuberculosis Research Articles

Declining incidence rate of tuberculosis among close contacts in five years post-exposure: a systematic review and meta-analysis

BackgroundIndividuals in close contact with active pulmonary tuberculosis (TB) patients showed a high risk of recent infection and, once infected, higher risk of developing active TB in the following years post-exposure. But the peak time of active disease onset is unclear. This study aims to estimate post exposure TB incidence risk among close contacts to provide reference for clinical and public health strategies.MethodsWe searched PubMed, Web of Science, and EMBASE for articles published until December 1, 2022. The incidence rates were quantitatively summarized by means of meta-analysis using the random-effect model.ResultsOf the 5616 studies, 31 studies included in our analysis. For baseline close contacts results, the summarized prevalence of Mycobacterium tuberculosis (MTB) infection and active TB was found to be 46.30% (95% CI: 37.18%-55.41%) and 2.68% (95% CI: 2.02%-3.35%), respectively. During the follow-up, the 1-year, 2-year and 5-year cumulative incidence of TB in close contacts were 2.15% (95% CI: 1.51%-2.80%), 1.21% (95% CI: 0.93%-1.49%) and 1.11% (95% CI: 0.64%-1.58%), respectively. Individuals with a positive result of MTB infection testing at baseline showed significantly higher cumulative TB incidence as compared to those negatives (3.80% vs. 0.82%, p < 0.001).ConclusionsIndividuals with close contact to active pulmonary TB patients are bearing significant risk of developing active TB, particularly within the first-year post-exposure. Population with recent infections should be an important priority for active case finding and preventive intervention worldwide.

The potential impact of vaccination on tuberculosis burden in India: A modelling analysis.

Vaccination will play an important role in meeting the end tuberculosis (TB) goals. While certain vaccine candidates in advanced stages of clinical trials raise hope for the future availability of new tools, in the immediate term, there is also increasing interest in Bacille Calmette-Guérin revaccination among adults and adolescents as a potential strategy. Here, we sought to estimate the potential epidemiological impact of TB vaccination in India. We developed a deterministic, age-structured, compartmental model of TB in India. Data from the recent national prevalence survey was used to inform epidemiological burden while also incorporating a vulnerable population who may be prioritized for vaccination, the latter consistent with the burden of undernutrition. Using this framework, the potential impact on incidence and mortality of a vaccine with 50 per cent efficacy was estimated, if rolled out in 2023 to cover 50 per cent of the unvaccinated each year. Simulated impacts were compared for disease- vs. infection-preventing vaccines, as well as when prioritizing vulnerable groups (those with undernutrition) rather than the general population. A sensitivity analyses were also conducted with respect to the duration, and efficacy, of vaccine immunity. When rolled out in the general population, an infection-preventing vaccine would avert 12 per cent (95% Bayesian credible intervals (Crl): 4.3-28%) of cumulative TB incidence between 2023 and 2030, while a disease-preventing vaccine would avert 29 per cent (95% Crl: 24-34%). Although the vulnerable population accounts for only around 16 per cent of India's population, prioritizing this group for vaccination would achieve almost half the impact of rollout in the general population, in the example of an infection-preventing vaccine. Sensitivity analysis also highlights the importance of the duration and efficacy of vaccine-induced immunity. These results highlight how even a vaccine with moderate effectiveness (50%) could achieve substantial reductions in TB burden in India, especially when prioritized for the most vulnerable.

Household Contact Tracing With Intensified Tuberculosis and Human Immunodeficiency Virus Screening in South Africa: A Cluster-Randomized Trial.

BackgroundHousehold contact tracing for tuberculosis (TB) may facilitate diagnosis and access to TB preventive treatment (TPT). We investigated whether household contact tracing and intensive TB/human immunodeficiency virus (HIV) screening would improve TB-free survival.MethodsHousehold contacts of index TB patients in 2 South African provinces were randomized to home tracing and intensive HIV/TB screening or standard of care (SOC; clinic referral letters). The primary outcome was incident TB or death at 15 months. Secondary outcomes included tuberculin skin test (TST) positivity in children ≤14 years and undiagnosed HIV.ResultsFrom December 2016 through March 2019, 1032 index patients (4459 contacts) and 1030 (4129 contacts) were randomized to the intervention and SOC arms. Of intervention arm contacts, 3.2% (69 of 2166) had prevalent microbiologically confirmed TB. At 15 months, the cumulative incidence of TB or death did not differ between the intensive screening (93 of 3230, 2.9%) and SOC (80 of 2600, 3.1%) arms (hazard ratio, 0.90; 95% confidence interval [CI], .66–1.24). TST positivity was higher in the intensive screening arm (38 of 845, 4.5%) compared with the SOC arm (15 of 800, 1.9%; odds ratio, 2.25; 95% CI, 1.07–4.72). Undiagnosed HIV was similar between arms (41 of 3185, 1.3% vs 32 of 2543, 1.3%; odds ratio, 1.02; 95% CI, .64–1.64).ConclusionsHousehold contact tracing with intensive screening and referral did not reduce incident TB or death. Providing referral letters to household contacts of index patients is an alternative strategy to home visits.Clinical Trials RegistrationISRCTN16006202.

The Risk of Developing Tuberculosis in Cancer Patients Is Greatest in Lymphoma: A Large Population-Based Study

Introduction: Patients with cancer, especially those diagnosed with hematological malignancies, are considered at higher risk for tuberculosis (TB). Several studies reported that Hodgkin lymphoma (HL) patients have the highest risk for TB among patients with hematological malignancies. These data are relatively old and based mostly on series of patients with malignancies or with TB but often lack statistical rigor and not based on large population-based studies.According to the Israeli regulations, every new diagnosis of cancer must be reported to the Israel National Cancer Registry (INCR) and every new diagnosis of TB to the Israel National Tuberculosis Registry (INTR). We combined both databases and studied epidemiological features of TB among patients with cancer in Israel, in which the incidence of TB in the general population is relatively low. The study objectives were to examine whether patients with hematological malignancies are at increased risk to develop active TB, compared to patients with solid tumors, and to examine whether patients with HL have a higher risk of active TB than patients with other hematological malignancies.Methods: The study population consists of all newly diagnosed cancer cases reported to the INCR from 1993-2013. These data were linked with data from the INTR for the same period. HIV patients were excluded from both databases. Hematologic malignancies were categorized into 5 groups: acute leukemia, HL, non-Hodgkin lymphoma (NHL), myelodysplastic syndrome/myeloproliferative neoplasm and plasma cell dyscrasia. Incidence rates per 100,000 person-years were calculated. Logistic regression was used to analyze the risk of TB following cancer diagnosis among patients with different malignancies.Results: Of 465,429 patients who were diagnosed with cancer during 1993-2013, 676 patients were notified to have TB but in only 321 patients the diagnosis of TB followed cancer diagnosis. The cumulative incidence of TB following cancer diagnosis was 14.4 per 100,000 person-years (PY). The rate of TB incidence following cancer diagnosis was 27.2/100,000 PY for persons diagnosed with hematological malignancies, and 12.7/100,000 PY among those with non-hematological malignancies (p<0.001). The highest TB incidence was found among patients with lymphoma (30.1 TB cases per 100,000 PY). Among lymphoma patients, a higher incidence rate was found in NHL patients than among HL patients, however the difference was not significant (32.1 vs . 21.6, respectively, p=0.378). Accounting for sex, age at diagnosis and ethnicity in logistic regression, the risk of TB among lymphoma patients is significantly higher than in other malignancies (Odds ratio 2.61, p=0.002) and there is no added significant risk for patients with HL (Odds ratio 1.33, p=0.464).Conclusions: 1) In this population-based study of more than 450,000 patients diagnosed with cancer, the incidence of TB following a cancer diagnosis is higher among patients with hematological malignancies than in patients with solid tumors. 2) Lymphoma patients have the highest risk to develop TB. 3) In contrast to common perception, we did not find that patients with HL are at increased risk to develop TB relative to NHL patients. 4) These data suggest for a heightened awareness for latent TB among newly diagnosed patients with lymphoma and for active TB among patients with a background of lymphoma who present with fever or respiratory complains. DisclosuresNo relevant conflicts of interest to declare.

Latent and active tuberculosis infection in allogeneic hematopoietic stem cell transplant recipients: a prospective cohort study.

Tuberculosis (TB) is a major infectious complication in hematopoietic stem cell transplant (HSCT) recipients in countries with high TB prevalence. Identifying and treating latent tuberculosis infection (LTBI) helps to prevent TB reactivation after transplantation. Few studies have compared the tuberculin skin test (TST) with interferon Gamma release assays (IGRA) to diagnose LTBI in HSCT candidates. We compared TST and QuantiFeron TB gold in tube (QTF-GIT) and prospectively evaluated the incidence of active tuberculosis in 126 HSCT candidates and 58 HSCT recipients with chronic GVHD followed at the outpatient clinic. TB was diagnosed by culture in Mycobacteria media and by commercial real-time PCR kit. Considering the positivity of any test, the prevalence of LTBI was 8.7% in HSCT candidates (11 out of 126) and 12.5% in HSCT recipients with chronic GVHD (6 out of 48). QTF-GIT indeterminate results were detected in 2.4% of the HSCT candidates. Fair to good agreement (K > 0.50) between tests was observed in both cohorts. Cumulative incidence of TB was 3% in the GVHD cohort. TB was diagnosed in 2 chronic GVHD recipients, both cases confirmed by positive culture and PCR. None of the 11 patients with LTBI diagnosed pre-HSCT who received INH prophylaxis developed TB.

Effectiveness of tuberculosis prophylaxis in patients with HIV/AIDS – retrospective analysis of data from Almaty, Kazakhstan, 2010–2015

According to data from the National Centre for Prevention and Control of AIDS, in the Republic of Kazakhstan, 45.8% of patients in the symptomatic stages of HIV infection are diagnosed with tuberculosis (TB) which is the cause of death in 36% of patients infected with HIV. The aim of the study was to conduct a retrospective analysis of the effectiveness of tuberculosis (TB) chemoprophylaxis among people living with HIV in the Republic of Kazakhstan (RK) in Central Asia. Materials and method. A retrospective analysis of patient health status was performed for each of the 648 patients (323 in the study group and 325 in the control group) during 2010-2015. Data from outpatient treatment charts were used concerning each patient infected with HIV observed at AIDS Treatment Centres. From among the 648 patients infected with HIV, 136 were receiving isoniazid in 2010, and 187 in 2011. The control group consisted of 325 people living with HIV (PLW HIV), who did not received isoniazid during observation. Results. The incidence of TB in patients who underwent chemoprophylaxis did not exceed 0.555/ 100,000 population in the first year of observation. Within 5 years, the TB incidence dropped to 0. In the control group, the TB incidence rate during the first year of observation was 3.262/100,000, with a decrease to 0.364 observed in 2015. Cumulated incidence rate in 2011-2015 in the study group accounted for 1.276/100,000. In the control group, the cumulative incidence was 4.3 times higher and accounted for 5.527. A significant difference in the mortality rate due to TB in the study and control groups was observed, the share of deaths due to TB in study group was 21.6% - nearly 3 times lower than in the control group (57.0%). Conclusions. The effectiveness of chemoprophylaxis for TB depends on biomedical, organizational and cultural factors. The presence of HIV co-infections is a special situation. Opposite to the majority of reports, in own study, no drug-resistant forms of tuberculosis were observed in relation with chemoprophylaxis with isoniazid. In the examined population, TB chemoprophylaxis reduced the incidence and cumulative incidence of TB among PLW HIV by 3.4-4.8 times. Isoniazid chemoprophylaxis decreased 4-fold the annual and cumulative mortality due to TB.

Absolute risk of tuberculosis among untreated populations with a positive tuberculin skin test or interferon-gamma release assay result: systematic review and meta-analysis

ObjectiveTo determine the annual rate of tuberculosis development after a positive tuberculin skin test (TST) or interferon-gamma release assay result (IGRA), or both, among untreated populations with characteristics believed to...

The risk of tuberculosis in cancer patients is greatest in lymphoma and myelodysplastic syndrome/myeloproliferative neoplasm: a large population-based cohort study

Patients with cancer are at high risk for tuberculosis (TB). This study combined the Israeli databases of cancer and TB and examined the development of TB among all newly diagnosed cancer cases from 1993 to 2013. Patients were classified into groups according to their different malignancies. Among 495,335 cancer patients, 335 developed TB following cancer diagnosis. The cumulative incidence of TB following cancer diagnosis was highest among MDS/MPN (148.8/100,000 patients) and lymphoma (154.1/100,000 patients) (p = .023). The HR of TB following cancer among hematologic patients was 2.51 (p < .001), relative to patients with in situ carcinomas/skin cancer and highest among MDS/MPN and lymphoma patients (2.74, p = .012 and 2.70, p < .001, respectively). Among lymphoma patients, a significant increased HR was found only among NHL patients (2.72, p < .001). The limitations include lack of information regarding risk factors for TB and of anti-cancer treatments. In conclusion, these data may encourage a heightened awareness for TB among patients with a background of lymphoma and MDS/MPN.

Incidence of tuberculosis is high in chronic kidney disease patients in South East England and drug resistance common

The risk of tuberculosis (TB) is significantly increased in chronic kidney disease (CKD). Data on TB in CKD in the UK are sparse; most information stems from countries with high background prevalence. The aim of this study was to estimate the incidence of TB in CKD patients in South East London and to describe the epidemiology, treatment, and outcome. CKD patients with TB between 1994 and 2010 were identified retrospectively. Data were collected on type of renal replacement therapy, the method of TB diagnosis, disease site, treatment regimens, and risk factors. Forty patients were identified of whom 67.5% had CKD stages IV–V. Sixty-five percent were from non-UK born ethnic minorities. Median time from diagnosis of CKD to TB development was 12 months (range 0–192 months). Cumulative incidence of TB was 1267/100,000 [95% confidence interval (CI): 630–1904; 85 × background UK rate] in hemodialysis patients; 398/100,000 (95% CI: 80–1160; 26 × background UK rate) in peritoneal dialysis; and 522/100,000 (CI: 137–909; 35 × background UK rate) in transplant recipients. Sixty-three percent of patients had pulmonary TB and 25% of patients with culture-positive TB had resistant isolates. Fifty percent of patients were immunosuppressed due to drugs, diabetes, and/or retroviral disease. Treatment regimens were according to recent national guidance in 73% of cases. Seventy-six percent of patients experienced side effects. Greater awareness of risk factors, drug resistance, treatment regimens, and potential side effects is needed.

Cumulative incidence of tuberculosis in lung cancer patients in Japan: A 6-year observational study.

Tuberculosis (TB) remains a health-related problem worldwide, and certain malignancies are known to be associated with an increased risk of TB. Lung cancer is the leading cause of cancer-related death, and the number of patients with lung cancer has been reportedly increasing. As the prognosis of lung cancer remains poor, aggressive comprehensive therapies have been used. The immunosuppression caused by cancer itself and treatment-associated immune modulation may increase the risk of TB. The present study was conducted to investigate the cumulative incidence of TB in lung cancer patients. This observational study included 904 consecutive patients diagnosed with histologically confirmed lung cancer from March 2007 to March 2013 and followed until March 2015 (mean 25.2 months). The cumulative incidence of TB was estimated using the Kaplan-Meier method. Nine lung cancer patients (1.00%) developed TB during the observation period. In all cases, TB occurred within 2 years of the diagnosis of lung cancer. The cumulative incidence of TB at 6 months, 1 year, and 2 years was 0.65%, 1.15%, and 1.38%, respectively. The cumulative incidence of TB in lung cancer patients was 1.38% in Japan.

Long-term risk of tuberculosis in haematopoietic stem cell transplant recipients: a 10-year nationwide study.

Tuberculosis (TB) is a serious problem for patients undergoing haematopoietic stem cell transplantation (HSCT) in TB-endemic areas; however, data on these patients are limited. We obtained data on 2040 HSCT recipients from the Registry of Catastrophic Illness in Taiwan from 1997 to 2006. We also obtained data on age-, sex- and enrolment date-matched controls from the Longitudinal Health Insurance Database. The cumulative incidence of active TB in HSCT recipients and controls and risk factors for TB were analysed. Among 2040 HSCT recipients identified, 39 (1.9%) had newly diagnosed TB. The incidence rate was 688 per 100 000 person-years. The 10-year cumulative TB incidence was respectively 3.52% and 0.38% in HSCT recipients and controls (P < 0.001). HSCT was an independent risk factor for TB compared with matched controls. Among post-HSCT patients, independent risk factors for TB included age ⩾18 years and allogeneic recipients with graft-versus-host disease (GVHD). Post-HSCT patients with subsequent TB had a higher mortality rate than those without TB (P < 0.001). HSCT is associated with an increased risk of TB in endemic regions. Older age and development of chronic GVHD are independent predictors of late onset active TB in HSCT recipients.

Increased risk of tuberculosis in patients with type 1 diabetes mellitus: results from a population-based cohort study in Taiwan.

The studies on the risk of tuberculosis (TB) in patients with type 1 diabetes mellitus (T1DM) alone are limited. We examined this relationship using a population-based retrospective cohort study. From claims data of the National Health Insurance system of Taiwan, we identified 5195 patients with T1DM newly diagnosed from 2002 to 2011 and 20,780 randomly selected controls without T1DM, frequency matched by age, sex, and year of diagnosis. Both cohorts were followed up until the end of 2011 to evaluate the risk of TB. The overall incidence of TB was 4.07-fold higher in the T1DM cohort than in the control cohort (1.18 vs 0.29 per 1000 person-years, P < 0.001). Compared with the controls, the Cox model estimated adjusted hazard ratios (HRs) of TB in patients with T1DM were greater in men than in women (4.62 vs 3.59) and in adults than in children (4.06 vs 3.37), but not significant. The adjusted HR was much greater for those with comorbidities than those without comorbidities (14.6 vs 1.62, P < 0.001). Compared with the controls, the patients with T1DM were also more likely to develop TB with multiple emergency room visits (adjusted HR: 116.1, 95% confidence interval [CI] = 43.8–307.4) or hospitalizations (adjusted HR: 86.5, 95% CI = 33.7–222.4). Patients with T1DM are at elevated risks of developing TB with much higher HRs for those with comorbidities, within the first year of diagnosis, and with frequent emergency cares or hospitalizations.

The potential effects of changing HIV treatment policy on tuberculosis outcomes in South Africa

Many countries are considering expanding HIV treatment following recent findings emphasizing the effects of antiretroviral therapy (ART) on reducing HIV transmission in addition to already established survival benefits. Given the close interaction of tuberculosis (TB) and HIV epidemics, ART expansion could have important ramifications for TB burden. Previous studies suggest a wide range of possible TB impacts following ART expansion. We used three independently developed TB-HIV models to estimate the TB-related impact of expanding ART in South Africa. We considered two dimensions of ART expansion--improving coverage of pre-ART and ART services, and expanding CD4-based ART eligibility criteria (from CD4 <350 to CD4 <500 or all HIV-positive). Three independent mathematical models were calibrated to the same data pertaining to the South African HIV-TB epidemic, and used to assess standardized ART policy changes. Key TB impact indicators were projected from 2014 to 2033. Compared with current eligibility and coverage, cumulative TB incidence was projected to decline by 6-30% over the period 2014-2033 if ART eligibility were expanded to all HIV positive individuals, and by 28-37% if effective ART coverage were additionally increased to 80%. Overall, expanding ART was estimated to avert one TB case for each 10-13 additional person-years of ART. All models showed that TB incidence and mortality reductions would grow over time, but would stabilize towards the end of the projection period. ART expansion could substantially reduce TB incidence and mortality in South Africa and could provide a platform for collaborative HIV-TB programs to effectively halt HIV-associated TB.

Results of Implementation of Preventive Recommendations for Tuberculosis After Renal Transplantation in an Endemic Area

This retrospective cohort study assessed the results of the implementation of preventive recommendations for tuberculosis (TB) among renal transplant recipients in an endemic area (Rio de Janeiro, Brazil). Subjects were defined as at high risk for TB if they had latent tuberculosis infection (LTBI), reported recent close contact with individuals with TB or received a graft from a donor with LTBI. A 6-month course of isoniazid preventive therapy (IPT) was targeted to high-risk subjects. The study end point was TB confirmed by culture. Altogether, 535 patients were included. Median follow-up was 59 months. The overall cumulative incidence of TB was 2.1% while among the 274 patients in whom the preventive protocol was fully implemented, the incidence was only 0.7%. The incidence of TB among 75 high-risk recipients not treated with isoniazid (7%) was significantly higher than that observed in 209 untreated low-risk patients (1%, p = 0.006) and in 65 high-risk subjects that received IPT (no case, p = 0.03). In conclusion, the implementation of preventive recommendations for TB in an endemic area allowed the appropriate discrimination between high- and low-risk renal transplant recipients and was associated with long-term reduction in the incidence of this complication among high-risk subjects.

Tuberculosis Incidence in HIV/AIDS Patients in Israel, 1983–2010

ObjectivesPeople living with HIV/AIDS (PLWHA) who develop tuberculosis disease are at greater mortality-risk. This study aimed to assess tuberculosis disease incidence among all PLWHA in Israel and identify populations at high-risk for developing tuberculosis.Design and MethodsRetrospective cohort-study based on the National HIV and Tuberculosis Registries, which were cross-matched and followed for the last 28-years. PLWHA who developed tuberculosis were compared to those who did not by the Cox-proportional analysis to generate hazard-ratios, and survival-analysis was performed by Log-Rank test.ResultsOf all the 6579 PLWHA reported between 1983 and 2010, corresponding to 55737 person-years, 384 (5.8%) developed tuberculosis. Of those, 14 were Israeli-born and 370 were non-Israeli born. The overall tuberculosis incidence-density was 6.9 cases/1000 person-years (95% CI 1.8–12.0). The cumulative tuberculosis-incidence among PLWHA in 2010 was 586 times higher than in HIV-negative individuals (3400 and 5.8 cases per 100000 population, respectively). Higher hazard-ratios to developing tuberculosis were found in migrant citizens PLWHA who were males, non-Israeli born, those who were diagnosed with HIV/AIDS after 1997, those who originated in high-tuberculosis prevalence country and those who acquired HIV by heterosexual or drug-injection transmission. PLWHA who developed tuberculosis had higher odds of dying than other PLWHA (36.5% and 16.6%, respectively, p<0.001, odds ratio = 2.8, 95% confidence-interval 2.3–3.6). In survival-analysis, time to develop tuberculosis was shorter among males than females, in PLWHA who were reported with HIV after 1997, in heterosexual who originated in high-tuberculosis countries, followed by injecting drug-users, heterosexual from low-tuberculosis burden countries and men who have sex with men.ConclusionTuberculosis-incidence is higher among non-Israeli born PLWHA, with decreasing trends from 1991. Despite the moderate TB-rate disease among PLWHA, it remains an important cause for severe morbidity and mortality. Tuberculosis in PLWHA reflects mainly the tuberculosis-burden in the originating country and possibly also the mode of HIV-transmission.

Immune restoration and onset of new AIDS-defining events with combination antiretroviral therapy in HIV type-1-infected immigrants in the Netherlands

We investigated differences in immune restoration and onset of new AIDS-defining events on combination antiretroviral therapy (cART) among HIV type-1 (HIV-1)-infected patients of different regional origin now living in the Netherlands. Treatment-naive adults reaching plasma viral load (pVL)<400 copies/ml within 9 months of starting cART were selected from the Netherlands ATHENA cohort. CD4(+) T-cell response on cART was determined over 7 years using mixed models. CD4(+) T-cell counts were excluded from the analyses at the first of two consecutive measurements of pVL≥400 copies/ml following prior suppression to <400 copies/ml. Multivariate analyses included gender, age, CD4(+) T-cell count and pVL prior to cART, hepatitis coinfection, HIV-1 transmission and region of origin (Western Europe/North America [WN], sub-Saharan Africa [SSA], Southeast Asia [SEA], Latin America/Caribbean [LAC] or other). For 6,057 selected patients (WN 3,947, SSA 989, SEA 237, LAC 695 and other 189), median follow-up was 3.2 years (WN 3.3, SSA 2.9, SEA 3.2, LAC 2.7 and other 2.7). CD4(+) T-cell increase in the first 6 months of cART was lower in males than females (-26 cells/mm(3); P<0.0001) and in patients from SSA compared with WN (-36 cells/mm(3); P<0.0001). Because men from SSA started with lower CD4(+) T-cell counts than men from WN, they continued to lag behind and had lower absolute CD4(+) T-cell counts after 7 years of cART. Furthermore, cumulative tuberculosis incidence after 7 years of cART was higher in SSA compared with WN (4.5% versus 0.5%, hazard ratio 5.08, 95% confidence interval 2.22-11.60). HIV-1-infected immigrants from SSA have blunted immune restoration on fully suppressive cART and should be identified at an earlier disease stage. Our results call for more intensive screening for both latent and active tuberculosis in these patients.

Efficacy of percutaneous versus intradermal BCG in the prevention of tuberculosis in South African infants: randomised trial

Objective To compare the incidence of tuberculosis over two years in infants vaccinated at birth with intradermal BCG or with percutaneous BCG.Design Randomised trial.Setting South Africa.Participants 11 680 newborn infants.Interventions...

Clinical Features and Outcome of Tuberculosis in Solid Organ Transplant Recipients

: Taiwan is an area with moderate to high incidence of Mycobacterium tuberculosis infection. The risk of M tuberculosis infection in transplantation recipients is considered to be significant. Our aim in this study was to investigate the clinical spectrums of M tuberculosis-infected transplantation recipients in a southeast Asian country, Taiwan. : We retrospectively analyzed the demographic data, clinical features, treatment, and outcome of M tuberculosis infection in kidney, heart, and liver transplant recipients from May 1996 to April 2005 at the National Taiwan University Hospital. : Fifteen patients who had received solid organ transplantation developed tuberculosis (kidney = 6, heart = 7, liver = 2). The median duration from transplantation to diagnosis of tuberculosis was 31 months. The cumulative incidence of post-transplantation tuberculosis was 2.0% (15/760), ie, approximately 3 times that of the general population. Ten patients (66.7%) had pulmonary tuberculosis, 1 (6.7%) had extrapulmonary tuberculosis, and 4 (26.7%) had disseminated tuberculosis. Nine patients completed the anti-tuberculosis treatment; the median treatment duration was 12 months (pulmonary: 9 months; extrapulmonary: 13.5 months). No treatment failure was noted in patients receiving the complete treatment course. The graft failure and mortality rates of post-transplantation tuberculosis were 13.3% each (2/15). The tuberculosis-associated mortality rate was 6.7% (1/15). : Cumulative incidence of tuberculosis was slightly higher in transplant recipients than in the general population in Taiwan. Conventional 4-combined anti-tuberculosis regimen for 12 months can treat the potentially fatal infection successfully in post-transplantation tuberculosis patients without recurrence.

Risk factors for Mycobacterium tuberculosis in US chronic dialysis patients

End-stage renal disease is known to disrupt the cell-mediated immune response that is responsible for the killing of intracellular organisms such as Mycobacterium tuberculosis. Risk factors that contribute to the development of tuberculosis (TB) disease in the US dialysis population have not been studied on a large scale. A retrospective cohort study of TB disease in 272,024 patients in the US Renal Data System initiated on dialysis therapy between 1 April 1995 and 31 December 1999 with Medicare or Medicaid as primary payer were analysed. A total of 21 risk factors were analysed. Among the US population studied, there is a 1.2 and 1.6% cumulative incidence of TB in patients undergoing either peritoneal or haemodialysis, respectively. Ten risk factors for TB that proved to be statistically significant included advanced age (P<0.001), unemployment (P<0.001), Medicaid insurance (P<0.001), reduced body mass index (P<0.001), decreased serum albumin (P<0.001), haemodialysis (P=0.019), both Asian (P=0.010) and Native American (P=0.020) race, ischaemic heart disease (P=0.032), smoking (P=0.010), illicit drug use (P=0.018) and anaemia (P=0.028). TB was independently associated with increased mortality, adjusted hazard ratio (AHR) 1.42 (95% CI 1.18-1.70, P<0.001). The prevalence of TB disease in the US dialysis population is low compared with worldwide rates; however, the disease is associated with increased mortality. Of the 10 significant risk factors identified, five are potentially modifiable.

Selective BCG vaccination in a country with low incidence of tuberculosis

In 1975 the BCG vaccination policy in Sweden changed from routine vaccination of all newborn infants to selective vaccination of groups at higher risk. This report aims to evaluate the present BCG policy, with focus on the tuberculosis situation in Sweden during the period from 1989 to 2005. The population structure in Sweden has changed, with increasing numbers and proportions of people who were born outside Sweden, especially in countries with high prevalence of tuberculosis. BCG vaccination coverage fell from more than 95% before 1975 to less than 2% in 1976 to 1980, and then again increased to around 16% (corresponding to about 88% of the risk group recommended for vaccination). The increasing proportion of foreign born tuberculosis patients among all tuberculosis cases of illness in Sweden, and the high age-specific incidence of tuberculosis in the childbearing age groups in the foreign-born population, indicate the need to continue selective vaccination of children in families originating from countries with high tuberculosis incidence. The cumulative incidence of tuberculosis in the 30 cohorts born in Sweden after 1974 and observed to the end of 2004 was estimated at 0.5 cases per 100 000 person-years. Sweden still has one of the lowest incidences of tuberculosis in the world, which means a minimal average risk of infection for the majority of children born to Swedish parents. The observed increase of tuberculosis in 2005, partly attributed to an outbreak at a day nursery, is a reminder of the serious consequences of delayed diagnosis. Intensified active case finding is the most important action to prevent childhood tuberculosis, by means of eliminating the sources of infection to prevent transmission to the child population. Early detection and treatment of infected children is necessary to prevent development of serious disseminated tuberculosis.