Negative Tuberculin Skin Test Results Research Articles

Evaluating Treatment Outcomes and Tuberculosis Infection Risks: A Comparative Study of Centralized Hospitalization vs. Home-Based Treatment.

Background: Guizhou Province in Southwest China has experimented with a centralized hospitalization (CH) treatment for active and severe cases of pulmonary tuberculosis (PTB). The objective of this study was to compare treatment outcomes of patients with tuberculosis (TB) receiving care in a CH setting with those receiving home-based (HB) care. In addition, this study aimed to assess the probability of their household contacts contracting tuberculosis infection. Method: A retrospective review of medical records was undertaken for patients with TB who completed their treatment in four counties in Guizhou, China, spanning from January 2022 to August 2023. In addition, a cross-sectional survey was conducted on the tuberculin skin test (TST) among household contacts of new patients with TB who had completed their treatment. Results: In the retrospective study, 94.8% had successful CH treatment, and 93.1% had successful HB treatment (p value = 0.70). In the prospective study, 559 and 448 household contacts of patients receiving CH treatment had 16 positive and 89 negative TST results, whereas those with HB treatment showed 26 positive and 74 negative TST results. Regarding a logistic regression analysis, the CH group was nearly two times more likely to test negative on the TST, 1.95 (95% CI: 0.98, 3.92). After adjusting for confounding variables, the odds ratio increased significantly to 4.42 (95% CI: 1.22, 16.04). Conclusions: CH for treatment of TB did not show superior success rates, but it may reduce the risk of transmitting tuberculosis infection to household contacts compared to home treatment.

Transboundary tuberculosis: Importation of alpacas infected with Mycobacterium bovis from the United Kingdom to Poland and potential for serodiagnostic assays in detecting tuberculin skin test false-negative animals.

The present study highlights the transboundary nature of tuberculosis (TB) in alpacas and the failure of current antemortem testing protocols to identify TB-free alpaca herds and individuals for exportation. The tuberculin skin test (TST) failed to identify Mycobacterium bovis-infected animals prior to movement from the United Kingdom (UK) to Poland. This study describes the use of four serological assays [Enferplex Camelid TB, dual-path platform (DPP) VetTB and BovidTB assays, and multi-antigen print immunoassays (MAPIAs)] to detect TB in an alpaca herd with negative TST results. The breeding in Poland purchased alpacas for several years from the UK with the last group arriving in May 2018. In July 2018, two sick alpacas from the centre were hospitalized in a veterinary clinic and both died of TB a few weeks later. In November 2018, 20 alpacas remaining in this M.bovis-affected herd were euthanized and samples were collected. The study population included 20 M.bovis-infected and 20 uninfected alpacas, but only 15 infected animals were tested by all serology tests. The DPP VetTB and DPP BovidTB assays detected antibodies in 14 of the 20 infected alpacas, with results confirmed by MAPIA, and in none (MAPIA and DPP BovidTB) or one (DPP VetTB) of the 20 uninfected animals. None of the infected alpacas tested positive using the Enferplex assay. In addition, the group included three orphans and two cria-dam pairs, which provided an opportunity to analyse immune aspects of cria-mother relationships in this herd. The results suggest high susceptibility of this host species to M.bovis infection and rapid progression to disease. The serological tests used in this study offer useful tools for the detection of M.bovis infection in TST and Enferplex test non-reactive alpacas. These tests should be further evaluated for implementation into TB management and control strategies for camelid species.

Evaluation of QuantiFERON tuberculosis Gold In-Tube assay for diagnosis of active tuberculosis in children.

Tuberculin skin test (TST) is still used in diagnostic algorithms of childhood tuberculosis (TB). QuantiFERON TB Gold In-Tube assay (QFT-GIT) is an alternative test to TST based on the detection of interferon-gamma release upon in vitro induction of peripheral mononuclear cells by TB antigens. In this study, we aimed to determine the diagnostic value and performance of QFT-GIT for active childhood TB. This retrospective study was conducted between January 2005 and December 2011 in three referral hospitals in Turkey with 124 children who were diagnosed with definite active TB. Sensitivity values of TST and QFT-GIT were determined by accepting the microbiological confirmation as the gold standard of diagnosis of TB. In our study, sensitivity of QFT-GIT and TST was found to be 65 and 66% respectively. However, combined usage of QFT-GIT and TST was found to be more sensitive (85%) than TST or QFT-GIT alone (P < 0.0001). Although negative results of QFT-GIT or TST did not exclude the diagnosis of active TB in children, their positivity supported the diagnosis. Specificity could not be measured as only microbiologically confirmed cases of Mycobacterium tuberculosis disease were enrolled in the study. Although sensitivities of TST and QFT-GIT are too low to exclude active TB, their positivity supports diagnosis of active TB in children concomitant with signs and symptoms. QFT-GIT and TST should be used together to enhance diagnostic sensitivity and could help exclude a diagnosis of TB if the pretest probability is low.

Tuberculosis household accompaniment to improve the contact management cascade: A prospective cohort study.

BackgroundAppropriate management of people exposed in the home to tuberculosis is essential to prevent morbidity. These household contacts, particularly children, should receive preventive therapy to prevent them from falling ill. However, few people receive preventive therapy worldwide. We sought to determine whether a community-based accompaniment intervention could improve tuberculosis contact management.MethodsWe conducted a prospective cohort study of household contacts of tuberculosis patients who initiated treatment during September 2015-June 2016 in Lima, Peru. Enrolled households received an intervention comprising home visits, transport vouchers, assistance coordinating evaluation procedures, and adherence support during preventive therapy. To evaluate the impact of the intervention, we conducted retrospective chart reviews of all patients initiating treatment during 6-month baseline and intervention periods.ResultsWe enrolled 314 household contacts of 109 index patients. Of these, 283 (90%) completed evaluation, and 4 (1%) were diagnosed with tuberculosis. Preventive therapy was prescribed for 35/38 (92%) contacts 0–19 years old who were eligible under Peruvian guidelines. Preventive therapy was also prescribed for 6/26 (23%) contacts with unknown eligibility due to lack of a tuberculin skin test (TST), and 20/69 (29%) who were ineligible either because of a negative TST result or exposure to a drug-resistant or extrapulmonary case. Of the 61 contacts who were prescribed preventive therapy, 57 (93%) initiated treatment, and 51 (91%) completed treatment. The proportion of contacts who completed evaluation increased from 42% during the baseline period to 71% during the evaluation period (risk ratio [RR] = 1.73, 95% confidence interval [95% CI]: 1.41–2.13). The proportion of contacts who initiated preventive therapy increased from 15% to 40% (RR = 2.45, 95% CI: 1.42–4.22).ConclusionAccompaniment of TB patient households greatly improved the evaluation of household contacts for TB and increased the use of preventive therapy.

Negative tuberculin skin test result predicts all-cause mortality among tuberculosis patients with HIV and diabetes comorbidity

PurposeThe purpose of this study was to determine if a negative tuberculin skin test (TST) result is associated with increased risk of mortality during tuberculosis (TB) treatment. MethodsWe conducted a retrospective cohort study among patients aged ≥15 years with culture-positive TB reported to the Georgia State Electronic Notifiable Disease Surveillance System from 2009 to 2014. TST positivity was defined by the US Centers for Disease Control guidelines. All-cause mortality during TB treatment as well as HIV, diabetes, and end-stage renal disease status were collected from surveillance data. Log-binomial regression was used to estimate adjusted risk ratios and 95% confidence intervals. ResultsAmong 1186 culture-confirmed TB patients, 780 (65.8%) with a valid TST and TB treatment outcomes were eligible. Nearly one-third (242/780) had a negative TST result, and 5.6% died during treatment. The highest risk of death was observed among patients with a negative TST and HIV (12.5%) and a negative TST and diabetes (15.4%). Adjusting for confounders, the risk of death among patients with a negative TST was significantly greater compared with those with a positive TST (adjusted risk ratio 2.33 95% confidence interval 1.23–4.43). ConclusionsA negative TST was associated with more than twice the risk of mortality during TB treatment after adjusting for immunosuppressive conditions.

Polymorphisms in TLR4 and TNFA and Risk of Mycobacterium tuberculosis Infection and Development of Active Disease in Contacts of Tuberculosis Cases in Brazil: A Prospective Cohort Study.

The role of genetic polymorphisms in latent tuberculosis (TB) infection and progression to active TB is not fully understood. We tested the single-nucleotide polymorphisms (SNPs) rs5743708 (TLR2), rs4986791 (TLR4), rs361525 (TNFA), rs2430561 (IFNG) rs1143627 (IL1B) as risk factors for tuberculin skin test (TST) conversion or development of active TB in contacts of active TB cases. Contacts of microbiologically confirmed pulmonary TB cases were initially screened for longitudinal evaluation up to 24 months, with clinical examination and serial TST, between 1998 and 2004 at a referral center in Brazil. Data and biospecimens were collected from 526 individuals who were contacts of 177 active TB index cases. TST conversion was defined as induration ≥5 mm after a negative TST result (0 mm) at baseline or month 4 visit. Independent associations were tested using logistic regression models. Among the 526 contacts, 60 had TST conversion and 44 developed active TB during follow-up. Multivariable regression analysis demonstrated that male sex (odds ratio [OR]: 2.3, 95% confidence interval [CI]: 1.1-4.6), as well as SNPs in TLR4 genes (OR: 62.8, 95% CI: 7.5-525.3) and TNFA (OR: 4.2, 95% CI: 1.9-9.5) were independently associated with TST conversion. Moreover, a positive TST at baseline (OR: 4.7, 95% CI: 2.3-9.7) and SNPs in TLR4 (OR: 6.5, 95% CI: 1.1-36.7) and TNFA (OR: 12.4, 95% CI:5.1-30.1) were independently associated with incident TB. SNPs in TLR4 and TNFA predicted both TST conversion and active TB among contacts of TB cases in Brazil.

The incidence of tuberculosis infection in hematopoietic stem cell transplantation recipients: A retrospective cohort study from a center in Turkey.

Immune-compromised patients with latent TB infection (LTBI) are at risk for TB reactivation and should receive prophylaxis. Whereas the tuberculin skin test (TST) has limitations particularly in immune-compromised patients. This retrospective study was conducted to determine the incidence of TB infection in adult HSCT recipients whose preventive therapy for LTBI was determined according to the guidance of targeted TST. Five hundred and fifty-eight consecutive HSCT recipients (287 autologous and 271 allogeneic) who survived ≥100days post-transplantation were included in this analysis. Tuberculin skin test results were available in 493 of 558 transplants (88.3%). The incidence of negative TST was 54.5% (269 of 493 patients). One multiple myeloma patient with a history of TB and negative TST result and was not on INH prophylaxis developed reactivation of TB infection. None of the recipients under INH prophylaxis (151 of 558 transplants; 27.1%) and none of the 224 patients with TST ≥5mm developed TB infection. Despite the limitations of being a retrospective analysis and variable prophylaxis thresholds of TST, there are some remarkable results of this analysis. We had no TB infection in the allogeneic HSCT recipients. The high incidence of negative TST results may be attributed to the underlying immune-deficiency. TST may not be a reliable guide for predicting TB reactivation risk in hematology patients. Tuberculin skin test may have a high rate of false-negative and false-positive results in HSCT recipients. The general guidelines for targeted TST to guide treatment of LTBI may not apply to all regions and situations. More reliable methods are required to predict and treat LTBI in these specific conditions.

Detection of latent tuberculosis infection in hemodialysis patients: Comparison between the quantiferon-tuberculosis gold test and the tuberculin skin test

BackgroundTuberculosis (TB) remains an important cause of morbidity and mortality in hemodialysis (HD) patients. A gold standard for the diagnosis of latent tuberculosis infection (LTBI) is lacking.ObjectiveThe aim of this study was to compare the diagnostic utility of the QuantiFERON-Tuberculosis Gold (QFT-G) test with the tuberculin skin test (TST) in identifying LTBI in patients with end-stage renal disease (ESRD) on HD.Study designThe present study had a prospective design.Patients and methodsA total of 74 patients with ESRD on HD without active TB and other immunosuppressive conditions were tested for LTBI by the QFT-G test and the TST.ResultsLTBI, as estimated by the QFT-G test and TST, was detected in 35.1 and 13.5% of the HD patients, respectively; 37.8% of patients were positive for the QFT-G test and/or the TST. There was a poor agreement between QFT-G test and TST results in patients with ESRD on HD (QFT-G test vs. TST: κ=0.25, 95% confidence interval=0.12–0.37). TST was positive in 2.7% of patients when the QFT-G test was negative, and it was negative in 24.3% of patients when the QFT-G test was positive. There was no significant difference in duration of HD or creatinine levels between QFT-G-positive and QFT-G-negative patients (P=0.08 and 0.2, respectively). TST-positive patients had a significantly shorter duration of HD and lower creatinine levels than TST-negative patients (P=0.001 and 0.01, respectively).ConclusionIn patients with ESRD and on HD, LTBI cannot be simply ruled out with a negative TST result, but rather a QFT-G test is recommended. Screening and treatment of LTBI should be carried in dialysis patients, aiming to prevent progression to active TB and secondary infection of others.

Comparative Evaluation of Allergodiagnostic of Tuberculosis in Children

The comparative analysis of results of the tuberculin skin test (TST) and of the skin test with the recombinant tuberculosis allergen (Diaskintest - DST) in 7978 children with active tuberculosis revealed for the first time in 2013 - 2014 was carried out. The negative DST result and positive TST result are observed at 551 (6.91%) of patients. 92 patients (1.15%) had negative both tests, and at 98 people (1.23%) DST has yielded positive result, PM - negative. Other patients had positive both tests. In general, by means of DST tuberculosis initially hasn't been revealed at 643 (8.06%) patients, and by means of TST - at 190 (2.38%) patients. The difference is statistically reliable (t = 9.16; P < 0.05). Dynamics of tests results at patients with active tuberculosis was studied. The result of DST remained negative for a year in18.7% of patients, in 26,7% of patients with initially negative DST the result became positive in 3 months, in 2.7% - a year after the first testing. Tuberculosis of various forms and localizations, including TB+, was diagnosed for children with initially negative results of DST and positive TST.

Clinical presentation of children with pulmonary tuberculosis: 25 years of experience in Lima, Peru.

To describe clinical presentation across age groups in 2855 children with pulmonary tuberculosis (TB) attending the Children's Hospital, Lima, Peru, to improve the diagnosis, treatment and care of childhood TB. Children aged 0-14 years admitted between 1 January 1973 and 31 December 1997 with active pulmonary TB were enrolled. Demographic information, history, physical examination data, laboratory and microbiological results, chest radiograph data, disease classification, treatment and adverse effect data, and outcome at the time of discharge were recorded by pulmonologists using detailed chart abstractions. Of the 2855 enrollees, 47% were malnourished and 56% had a household contact. Older children presented with classic TB symptoms, while weight loss and anorexia were rare in children aged <5 years. Microbiological or pathologic confirmation was obtained in 71% of children aged 10-14 years compared with 34% of children aged <2 years; however, severe extra-pulmonary TB was most common among children aged <2 years (41%). Classic TB symptoms should be considered when making a diagnosis; however, systematic symptoms among young children are also important. In high-burden settings, clinicians should have a low threshold to diagnose and treat children for TB across all ages, even in the context of a negative tuberculin skin test result and lack of micro-pathological confirmation.

T-Cell Profiling and the Immunodiagnosis of Latent Tuberculosis Infection in Patients with Inflammatory Bowel Disease

Factors associated with performance of interferon-γ release assays (IGRA) and the tuberculin skin test (TST) in screening for latent tuberculosis infection in patients with inflammatory bowel diseases (IBD) are still poorly understood. The influence of peripheral T-cell subset counts on the results also remain unclear. Prospective single-center study in 205 patients with IBD. Latent tuberculosis infection screening included a chest radiograph, TST (retest if negative), and 2 IGRAs: QuantiFERON-TB Gold In-Tube (QFT-GIT) and TSPOT-TB (TSPOT). T-cell subpopulations were determined by flow cytometry. Twenty-one (10.2%) patients had an abnormal chest radiograph, 55 (26.8%) had a positive TST, 16 (7.8%) had a positive QFT-GIT, and 25 (12.6%) had a positive TSPOT. TST positivity was lower in patients on ≥2 immunosuppressants compared with the controls (5-aminosalicylic acid treatment) (10.4% versus 38.2%, respectively) (P = 0.0057). No other drugs influenced TST or IGRA positivity. In patients on corticosteroid treatment, anti-TNF treatment, or ≥2 immunosuppressants, IGRAs detected 10 cases of latent tuberculosis infection not identified by TST. TSPOT and QFT-GIT increased yield by 56% and 22%, respectively. No significant differences in T-cell subpopulations were found between patients with positive or negative TST or TSPOT results. However, patients with positive QFT-GIT findings had more CD8 T cells (mean, 883 ± 576 versus 484 ± 385 cells per microliter in patients with negative results) (P = 0.022). IGRAs can improve TST-based screening in patients with IBD on immunosuppressive therapy. A low CD8 count can affect QFT-GIT results. We suggest combining TSPOT and TST screening in patients with IBD on immunosuppressants.

Poor agreement between QuantiFERON-TB Gold test and tuberculin skin test results for the diagnosis of latent tuberculosis infection in rheumatoid arthritis patients and healthy controls

Background/AimsWe investigated the agreement between the QuantiFERON-TB Gold (QFT-Gold) test and the tuberculin skin test (TST) in the diagnosis of latent tuberculosis infection in patients with rheumatoid arthritis (RA), compared with healthy controls, in Korea.MethodsWe recruited 64 patients with RA and 79 healthy controls at two university hospitals in South Korea. The participants underwent both the QFT-Gold test and the TST simultaneously between August 2006 and February 2009. All patients were diagnosed using the classification criteria for RA revised in 1987 by the American College of Rheumatology. Bacillus Calmette-Guérin vaccination status and current medications were evaluated, and disease activities were assessed using the Disease Activity Score in 28 joints. Eleven patients with RA produced indeterminate QFT-Gold test results and were thus excluded from the kappa analysis.ResultsBased on an induration of 10 mm in diameter as the TST cutoff value, the QFT-Gold test and TST demonstrated 75.0% agreement (κ = 0.23) in patients with RA and 75.9% agreement (κ = 0.19) in healthy controls. Among the 56 patients with RA who had negative TST results, 11 patients (17.2%) also yielded indeterminate QFT-Gold results.ConclusionsOur study showed poor agreement between the results of the QFT-Gold test and the TST in both RA patients and healthy controls. Based on these findings, we emphasize the importance of making clinical decisions in the diagnosis of latent tuberculosis in Koreans with or without RA.

T-SPOT.TB for Detection of Tuberculosis Infection among Hematological Malignancy Patients and Hematopoietic Stem Cell Transplant Recipients

The diagnosis of latent Mycobacterium tuberculosis infection (LTBI) is recommended in hematological malignancy patients and before hematopoietic stem cell transplantation (Guidelines for the prevention and management of infectious complications of solid organ transplantation, 2004). Compared to traditional methods such as tuberculin skin test (TST), T-SPOT.TB has been shown to be more specific. In the present study we enrolled 536 patients for whom T-SPOT.TB was performed, among which 295 patients also received the TST test. The agreement (79%) between T-SPOT.TB and TST was poor (?=0.274, P<0.001). The patients with positive T-SPOT.TB results numbered 62 (11.6%), in which only 20 (48.8%) of the 41 receiving the TST test had positive results. A majority of the patients with T-SPOT.TB positive results had some other evidence ofTB, such as TB history, clinical symptoms and an abnormal chest CT scan. Active TB was found in 9 patients, in which 2 had negative TST results. We followed up the patients and no one developed active TB. Our study suggested that the T-SPOT.TB may be more useful for screening LTBI and active TB in hematological malignancy patients and hematopoietic stem cell transplant recipients than the TST test.

Tuberculin skin testing in inflammatory bowel disease patients from an endemic area of Brazil

ObjectiveInflammatory bowel disease (IBD) is a chronic disorder involving the gastrointestinal tract. Immunosuppressive drugs are usually prescribed to treat IBD patients, and this treatment can lead to tuberculosis reactivation. This paper aimed to analyze tuberculin skin test (TST) results in IBD patients at a reference center in Brazil. MethodsWe evaluated TST results in IBD patients using a cross-sectional study. We also analyzed the medical records of patients treated at a reference IBD outpatient unit where TST is routinely performed. ResultsWe reviewed 119 medical records of 57 (47.9%) Crohn's disease (CD), 57 (47.9%) ulcerative colitis (UC) and 5 (4.2%) indeterminate colitis (IC) patients. The mean (SD) age was 43.5 (13.7) years old. TST was positive in 24 (20.2%) of the patients. TST was positive in 16/57 (28.1%) UC and 6/57 (10.5%) CD patients (prevalence ratio [PR] 2.7). Forty-one patients (34.5%) were taking immunosuppressive drugs (azathioprine or prednisone) at the time of the TST, and six of these patients (14.6%) had positive test results. Two patients using infliximab had negative TST results. Thirty-five of the 41 patients (85.4%) on immunosuppressive treatment were anergic compared with 73.1% (57/78) of the untreated patients (PR 1.2). ConclusionsPatients with IBD have TST results similar to the general Brazilian population. Within the IBD population, CD patients have a lower frequency of TST positivity than UC patients.

Cost of Annual Tuberculosis Screening of Healthcare Workers with Negative Tuberculin Skin Test Results

The Centers for Disease Control and Prevention (CDC) recommends annual screening for Mycobacterium tuberculosis infection using the tuberculin skin test (TST) for individuals working in hospitals with 200 or more inpatient beds that have at least 6 documented cases of active tuberculosis (TB) per year. The cost of annual TB screening programs is significant, but the cost per individual with TST conversion is unknown. Therefore, we evaluated the annual TB screening program at the Johns Hopkins Hospital and Medical School to determine (1) the proportion of individuals with TST conversion among individuals in the annual TB screening program with patient care exposure at the Johns Hopkins Hospital and Medical School, (2) which employment and demographic factors are associated with TST conversion, (3) the prevalence of active TB disease among those with TST conversion, and (4) the annual cost of subsequent screening of individuals with initial negative TST results and the screening cost per individual with TST conversion.TST results were reviewed for individuals participating in the annual TB screening program during the previous 4 years (2007–2010) at the Johns Hopkins Hospital and Medical School, which has experienced an average of 12 documented cases of active TB per year. TST was performed before employment and then annually for healthcare providers according to CDC guidelines and the manufacturer's directions. Individuals in the testing program included anyone who had patient contact, such as physicians, nurses, technologists, students, phlebotomists, nutritionists, pharmacists, and clerks. All initial testing was 2-step testing if the individual was initially reactive.

A Quantitative Benefit-Risk Analysis of Isoniazid for Treatment of Latent Tuberculosis Infection Using Incremental Benefit Framework

BackgroundWe undertook a quantitative benefit-risk analysis of a targeted isoniazid (INH) therapy for latent tuberculosis (TB) infection for different groups of contacts of active TB cases. MethodsWe developed a decision-analytic model to compare the treatment of latent TB infection in subgroups of contacts to no treatment over a 6-year time horizon in a Canadian setting. Contacts were stratified into 32 groups on the basis of five binary variables: type of contact (close or casual), tuberculin skin test (TST) results (positive or negative at 5 mm cutoff), Bacillus Calmette-Guérin vaccination status, place of birth (foreign- or Canadian-born), and age group (cutoff 35 years). Risk of TB reactivation was calculated for each subgroup from a longitudinal registry of contacts, adjusted for several potential confounders and comorbid conditions. We calculated the quality-adjusted life-years gained because of delayed or prevention of active TB via treatment of latent TB infection versus quality-adjusted life-years lost because of the adverse events to INH. ResultsA targeted policy based on adopting INH therapy only in subgroups with positive expected incremental net health benefit resulted in a different treatment decision than the current guidelines in five subgroups comprising 3.9% of the contacts. Namely, the targeted policy comprised no INH therapy in casual contacts with a positive vaccination history even with a positive TST result and INH therapy in foreign-born close contacts younger than 35 years even with a negative TST result. ConclusionsFrom a benefit-risk viewpoint, INH treatment of contacts should be tailored on the basis of risk assessment algorithms that consider a range of factors at the time of screening.

Tests for Latent Tuberculosis in People With ESRD: A Systematic Review

The relative diagnostic accuracy of interferon γ release assays (IGRAs; based on ELISA [enzyme-linked immunosorbent assay] or ELISPOT [enzyme-linked immunosorbent spot], ie, the QuantiFERON and T-SPOT.TB tests, respectively) and the tuberculin skin test (TST) for latent tuberculosis (TB) infection in people with end-stage kidney disease is uncertain and national guidelines for their use are inconsistent. Systematic review. Evaluated performance of tests for latent TB with clinical risk-factor assessment. People with end-stage kidney disease (chronic kidney disease stage 5 [eGFR <15] or kidney transplant recipients). No limits on setting. ELISA- or ELISPOT-based IGRAs, TST, assays to detect antimycobacterial antibodies, and flow cytometry-based tests. Odds of test positivity with clinical risk factor for latent TB, expressed as ORs and relative ORs (RORs). 47 studies (6,828 participants) were included, but only 30 studies (4,546 participants) contained sufficient data to contribute to meta-analysis. Studies were predominately in the dialysis population (23/30; 3,700 participants) in countries with low to moderate TB prevalence (0.0-50.0 cases/10(5) persons). BCG vaccination rate was variable (2.7%-100.0%). 9 studies compared IGRAs with the TST directly, 17 studies evaluated the TST only, and the other 4 studies evaluated other tests. Compared to a positive TST result, a positive ELISA-based IGRA result was associated more strongly with radiologic evidence of past TB (ROR, 4.29; 95% CI, 1.83-10.3; P = 0.001) and contact with active TB (ROR, 3.36; 95% CI, 1.61-7.01; P = 0.001). Compared to a negative TST result, a negative ELISA-based IGRA result was associated more strongly with BCG vaccination (ROR, 0.30; 95% CI, 0.14-0.63; P = 0.002). There were insufficient data to compare performance of the ELISPOT-based IGRA with the TST or ELISA-based IGRA. 17 of 47 included studies (36.2%) did not contain sufficient data to contribute to meta-analysis. Compared to the TST, the ELISA-based IGRA was associated more strongly with risk factors for latent TB in end-stage kidney disease.

An Outbreak of Tuberculosis Among Adults With Mental Illness

An Outbreak of Tuberculosis Among Adults With Mental Illness

Risk factors for tuberculin skin test conversion among HIV-infected patients in New York City

We assessed the incidence of and risk factors for tuberculin skin test (TST) conversion among HIV-infected adults at a New York City clinic. All adult HIV-infected patients were eligible for inclusion if they had a negative baseline TST result and at least one subsequent documented TST test result. A total of 414 HIV-infected patients had a negative baseline TST result; 288 (69.6%) were male. Among 348 patients who had a place of birth documented, 50% were born outside of mainland USA. Twenty-two (5.3%) of 414 patients had documented TST conversions, giving a crude incidence rate of 1.77 per 100 person-years. Being a foreign-born Asian individual (p=0.02), having lived in a shelter (p=0.004), and having an increase in CD4 cell count (p=0.02) while under care were independent risk factors for TST conversion. We found a high TST conversion rate among HIV-infected patients attending an urban clinic. Annual TST testing is particularly important for patients who are foreign-born from high-endemic countries, those with a history of homelessness, and those with an increase in CD4 cell count since the baseline negative TST test.

Risk of developing tuberculosis after brief exposure in Norwegian children: results of a contact investigation

ObjectiveProlonged exposure to adults with pulmonary tuberculosis is a risk factor for infecting children. We have studied to what extent a brief exposure may increase the risk of being infected...