A five-year analysis of latent tuberculosis infection in Queensland, 2016-2020.

Background Australia is aiming to reach tuberculosis pre-elimination targets by 2035. As a low-incidence setting, control efforts will increasingly rely on the management of latent tuberculosis infection (LTBI). We undertook this descriptive analysis to assess the recent trends of LTBI testing in Queensland. Methods Our objective was to describe the features of LTBI testing in Queensland, and to estimate the range of possible annual notifications were it to be made a notifiable condition. We collated both state-wide and region-specific data on tuberculin skin testing (TST) and interferon gamma release assays (IGRA) conducted in Queensland during the five-year period 1 January 2016 - 31 December 2020. We used reports on Medicare-funded TST and IGRA testing in Queensland, as well as tuberculosis notification data, to understand the representativeness of our data and to derive state-wide estimates. Results We analysed 3,899 public TST, 5,463 private TST, 37,802 public pathology IGRA, and 31,656 private pathology IGRA results. The median age of people tested was 31 years; 57% of those tested were female. From our data sources, an annual average of 1,067 positive IGRA and 354 positive TST results occurred in Queensland. Building on this minimum value, we estimate possible latent tuberculosis notifications in Queensland could range from 2,901 to 6,995 per annum. Private laboratory TSTs are estimated to contribute the lowest number of potential notifications (range: 170-340), followed by private laboratory IGRA testing (range: 354-922), public laboratory IGRA testing (range: 706-1,138), and public setting TSTs (range: 1,671-4,595). Conclusion If LTBI were to be made notifiable, these estimates would place it among the ten most notified conditions in Queensland. This has implications for potential surveillance methods and goals, and their associated system and resource requirements.

Association of vitamin D levels and risk of latent tuberculosis in the hemodialysis population.

BACKGROUND: Vitamin D is essential in the host defense against tuberculosis (TB). Suboptimal vitamin D status is common in the hemodialysis population. Hemodialysis patients have an increased risk compared to the general population latent tuberculosis infection (LTBI). However, the association between vitamin D deficiency and LTBI in this population remains unclear. MATERIALS AND METHODS: We conducted a cross-sectional study between March and May 2017. Interferon-gamma release assay (IGRA) through QuantiFERON-TB Gold In-Tube was used to assess LTBI. Plasma 25-hydroxycholecalciferol (25-OHD) levels were measured by Elecsys Vitamin D Total assay. Suboptimal vitamin D levels included vitamin D insufficiency 20-29 ng/mg and vitamin D deficiency <20 ng/mL. Predictors for LTBI were analyzed. RESULTS: A total of 287 participants were enrolled. The suboptimal vitamin D level was 31.4% (90/287), which including the vitamin D deficiency was 13.9% (40/287). A total of 49.1% (141/287) people received nutritional vitamin D supplementation. The prevalence of IGRA positivity in this study was 25.1% (72/287). There was no significant difference in vitamin D concentrations or the proportion of vitamin D supplementation among the IGRA-positive and IGRA-negative groups (p = 0.789 and 0.496, respectively). In multivariate analysis, age >65 years old (odds ratio (OR), 1.89; 95% CI, 1.08-3.31; p = 0.026) and TB history (OR, 3.51; 95% CI, 1.38-8.91; p = 0.008) were independent predictors of IGRA positivity. CONCLUSION: This is the first study to report that vitamin D deficiency was not associated with IGRA positivity in a hemodialysis population. Aging and TB history were both independent predictors for LTBI.

Hyperbaric oxygen therapy increases the risk of tuberculosis disease.

BACKGROUND: As Mycobacterium tuberculosis is an aerobic microbe, hyperbaric oxygen therapy (HBOT) could trigger progression from latent tuberculous infection (LTBI) to active tuberculosis (TB) disease. OBJECTIVE: To evaluate the effect of HBOT on TB reactivation. DESIGN: Our study sample was from the National Health Insurance Research Database containing one million beneficiaries. We identified a group of patients who underwent HBOT, and matched this group with individuals without HBOT. We compared the incidence of activation of TB between these two groups. RESULTS: A total of 2258 patients were identified, with each group comprising 1129 patients. One year after exposure to hyperbaric oxygen, the number of cases of active TB was significantly higher in the HBOT group than in the non-HBOT group (11 cases vs. 1 case, P = 0.006). Multiple regression analysis showed that HBOT was the only statistically significant contributor to TB activation. CONCLUSION: HBOT is likely to trigger the reactivation of TB. High-risk patients should undergo the tuberculin skin test or interferon-gamma release assays before HBOT to identify patients with LTBI.

Documento de consenso sobre la prevención y el tratamiento de la tuberculosis en pacientes candidatos a tratamiento biológico / Consensus Document on Prevention and Treatment of Tuberculosis in Patients for Biological Treatment

El riesgo de enfermar de tuberculosis ha aumentado en los pacientes con enfermedades inflamatorias crónicas que reciben tratamiento inmunosupresor, en particular en aquellos tratados con terapia anti-TNF (del inglés tumor necrosis factor). En estos pacientes es obligatoria la detección de la infección tuberculosa latente y el tratamiento de dicha infección, dirigido a reducir el riesgo de progresión a enfermedad tuberculosa. Este documento de consenso resume la opinión de expertos y los conocimientos actuales sobre tratamientos biológicos, incluidos los bloqueantes del TNF. Se establecen recomendaciones para la utilización de las técnicas de liberación de interferón-gamma (IGRA) y la prueba de la tuberculina (PT) para el diagnóstico y el tratamiento de la infección tuberculosa latent

Tuberculosis risk is increased in patients with chronic inflammatory diseases receiving any immunosuppressive treatment, notably tumor necrosis factor (TNF) antagonists therapy. Screening for the presence of latent infection with Mycobacterium tuberculosis and targeted preventive treatment to reduce the risk of progression to TB is mandatory in these patients. This Consensus Document summarizes the current knowledge and expert opinion of biologic therapies including TNF-blocking treatments. It provides recommendations for the use of interferon-gamma release assays (IGRA) and tuberculin skin test (TST) for the diagnosis of latent tuberculosis infection in these patients, and for the type and duration of preventive therapy

Impact of cytotoxic and targeted antineoplastic drugs on the validity of the mitogen-induced interferon-gamma release assay for latent tuberculosis infection: results of a prospective trial at a comprehensive cancer center.

Abstract The T-SPOT.TB test (TS.TB), an interferon-gamma (IFN-γ) release assay (IGRA), is superior in diagnosing latent tuberculosis infection compared with the conventional tuberculin skin test (TST). However, whether cytotoxic chemotherapy and treatment with new-generation antineoplastic monoclonal antibodies affects the TS.TB is not certain. We evaluated the feasibility of using the TS.TB in this population. Sixteen cancer patients at high risk for tuberculosis exposure were prospectively evaluated with the TST and TS.TB. Blood samples were obtained 7.5 ± 89.3 days after the most recent cycle of antineoplastic therapy. Six patients (38%) were febrile within 24 h of blood sampling; high-dose corticosteroid therapy and profound treatment-induced neutropenia were present in 1 patient each. In all patients, TS.TB showed no evidence of latent tuberculosis infection. A robust mitogen-induced IFN-γ response was seen in samples from 14 patients (88%) despite therapy with high-dose corticosteroids, cyclophosphamide, fludarabine, gemtuzumab ozogamicin, and alemtuzumab. The presence of fever or profound neutropenia did not negatively impact mitogen response by peripheral lymphocytes. The 2 patients whose peripheral blood lymphocytes (> 500 cells/ml) failed to generate a cytokine response to ex vivo mitogen stimulation had refractory advanced cancer. Unlike the TST, a negative TS.TB provided interpretable results even in cancer patients undergoing new-generation immunosuppressive therapy.