Optimal Testing Choice and Diagnostic Strategies for Latent Tuberculosis Infection Among US-Born People Living with Human Immunodeficiency Virus (HIV)

Examining Test Cutoffs to Optimize Diagnosis of Latent Tuberculosis Infection in People Born Outside the United States

Rationale: Detection of latent tuberculosis infection (LTBI) in persons born in high tuberculosis (TB) incidence countries living in low TB incidence countries is key to TB elimination in low-incidence countries. Optimizing LTBI tests is critical to targeting treatment. Objectives: To compare the sensitivity and specificity of tuberculin skin test (TST) and two interferon-γ release assays at different cutoffs and of a single test versus dual testing. Methods: We examined a subset (N = 14,167) of a prospective cohort of people in the United States tested for LTBI. We included non-U.S.-born, human immunodeficiency virus-seronegative people ages 5 years and older with valid TST, QuantiFERON-TB Gold-in-Tube (QFT), and T-SPOT.TB (TSPOT) results. The sensitivity/specificity of different test cutoffs and test combinations, obtained from a Bayesian latent class model, were used to construct receiver operating characteristic (ROC) curves and assess the area under the curve (AUC) for each test. The sensitivity/specificity of dual testing was calculated. Results: The AUC of the TST ROC curve was 0.81 (95% credible interval (CrI), 0.78-0.86), with sensitivity/specificity at cutoffs of 5, 10, and 15 mm of 86.5%/61.6%, 81.7%/71.3%, and 55.6%/88.0%, respectively. The AUC of the QFT ROC curve was 0.89 (95% CrI, 0.86-0.93), with sensitivity/specificity at cutoffs of 0.35, 0.7, and 1.0 IU/mL of 77.7%/98.3%, 66.9%/99.1%, and 61.5%/99.4%. The AUC of the TSPOT ROC curve was 0.92 (95% CrI, 0.88-0.96) with sensitivity/specificity for five, six, seven, and eight spots of 79.2%/96.7%, 76.8%/97.7%, 74.0%/98.6%, and 71.8%/99.5%. Sensitivity/specificity of TST-QFT, TST-TSPOT, and QFT-TSPOT at standard cutoffs were 73.1%/99.4%, 64.8%/99.8%, and 65.3%/100%. Conclusion: Interferon-γ release assays have a better predictive ability than TST in people at high risk of LTBI.

Practices and attitudes towards tuberculosis and latent tuberculosis infection screening in people living with HIV/AIDS among HIV physicians in Japan

Background

Tuberculosis (TB) continues to be the leading cause of death for people living with HIV/AIDS (PLHIV), and HIV is the strongest known risk factor for progression to active TB disease for persons with latent TB infection (LTBI). Screening for active TB and LTBI, and TB preventive therapy (TPT) is recommended, however, clinical practices regarding LTBI screening for HIV positive population have not been uniform, resulting in low rates of LTBI screening and TPT uptake, in both low and high TB-burden countries. We sought to explore the practices and attitudes towards TB and LTBI screening in PLHIV among HIV physicians in Japan.

Methods

We conducted a cross-sectional survey whereby an on-line questionnaire was administered to physicians who are currently, or have the experience of, providing care and treatment for PLHIV in Japan.

Results

The questionnaire was sent to a total of 83 physicians, of which 59 responded (response rate; 71.1%). 52.5% (31/59) conducted routine screening and 44.0% (26/59) conducted selectively screening for active TB among HIV/AIDS patients. As for LTBI, 54.2% (32/59) conducted routine screening and 35.6% (21/59) conducted selective screening for LTBI among PLHIV. “T-SPOT only” was the most frequently used method of screening (n = 33), followed by “QFT only” (n = 11). Criteria for LTBI screening included TB burden in the country of birth of the patient, previous contact with a TB patient, and CD4+ cell count. 83.1% (49/59) either “always” or “selectively” offered TPT to PLHIV diagnosed with LTBI, and among the 49 respondents who did provide TPT, 77.6% (38/49) chose 9-months isoniazid as their first choice. None chose regimen including rifampicin.

Conclusions

Our study revealed that practices regarding TB and LTBI screening and treatment for PLHIV among HIV physicians were mixed and not necessarily in accordance with the various published guidelines. Building and disseminating scientific evidence that takes into consideration the local epidemiology of TB and HIV in Japan is urgently needed to assist physicians make decisions.

Care cascade of tuberculosis infection treatment for people living with HIV in the era of antiretroviral therapy scale-up

Testing and treatment of tuberculosis infection (TBI) are recommended for people living with HIV (PLWH). We aimed to evaluate the care cascade of TBI treatment among PLWH in the era of antiretroviral therapy (ART) scale-up. This retrospective study included adult PLWH undergoing interferon-gamma release assay (IGRA)-based TBI screening during 2019–2021. PLWH testing IGRA-positive were advised to receive directly-observed therapy for TBI after active TB disease was excluded. The care cascade was evaluated to identify barriers to TBI management. Among 7951 PLWH with a median age of 38 years and CD4 count of 616 cells/mm³, 420 (5.3%) tested positive and 38 (0.5%) indeterminate for IGRA. The TBI treatment initiation rate was 73.6% (309/420) and the completion rate was 91.9% (284/309). More than 80% of PLWH concurrently received short-course rifapentine-based regimens and integrase strand transfer inhibitor (InSTI)-containing ART. The main barrier to treatment initiation was physicians’ concerns and patients’ refusal (85.6%). The factors associated with treatment non-completion were older age, female, anti-HCV positivity, and higher plasma HIV RNA. Our observation of a high TBI completion rate among PLWH is mainly related to the introduction of short-course rifapentine-based regimens in the InSTI era, which can be the strategy to improve TBI treatment uptake.

Diagnosis and treatment of tuberculosis in adults with HIV

Mycobacterium tuberculosis, the causative agent of tuberculosis (TB), continues to pose a major public health problem and is the leading cause of mortality in people infected with human immunodeficiency virus (HIV). HIV infection greatly increases the risk of developing TB even before CD4+ T-cell counts decrease. Co-infection provides reciprocal advantages to both pathogens and leads to acceleration of both diseases. In HIV-coinfected persons, the diagnosis and treatment of tuberculosis are particularly challenging. Intensifying integration of HIV and tuberculosis control programmes has an impact on reducing diagnostic delays, increasing early case detection, providing prompt treatment onset, and ultimately reducing transmission. In this Review, we describe our current understanding of how these two pathogens interact with each other, new sensitive rapid assays for TB, several new prevention methods, new drugs and regimens.