The definition of tuberculosis infection based on the spectrum of tuberculosis disease

Abstract

Latent tuberculosis infection was the term traditionally used to indicate tuberculosis (TB) infection. This term was used to define “a state of persistent immune response to stimulation by Mycobacterium tuberculosis antigens through tests such as the tuberculin skin test (TST) or an interferon-γ release assay (IGRA) without clinically active TB”. Recent evidence indicates that the spectrum from TB infection to TB disease is much more complex, including a “continuum” of situations didactically reported as uninfected individual, TB infection, incipient TB, subclinical TB without signs/symptoms, subclinical TB with unrecognised signs/symptoms, and TB disease with signs/symptoms. Recent evidence suggests that subclinical TB is responsible for important M. tuberculosis transmission. This review describes the different stages described above and their relationships. It also summarises the new developments in prevention, diagnosis and treatment of TB infection as well as their public health and policy implications.Educational aimsTo describe the evolution of the definition of “tuberculosis infection” and didactically describe the continuum of stages existing between TB infection and disease.To discuss the recommended approaches to prevent, diagnose and treat TB infection.

Screening for Tuberculosis in Migrants: A Survey by the Global Tuberculosis Network

“…The overwhelming majority of participants agreed on the importance of implementing a register-based surveillance of TBI to inform progress towards global TB elimination [ 19 , 20 , 21 ].…”

“…The main areas of disagreement among participants in our study related to the optimal test used to diagnose TB infection (TST or IGRAs) and the best regimen to treat it. The advantages and disadvantages of IGRAs and the TST have been widely debated [ 21 ]. Compared to the TST, IGRAs do not rely on the subjective reading of a skin induration by a HCW, only require a single patient visit, have generally better sensitivity and specificity, and are not impacted by previous BCG vaccination or exposure to non-tuberculous mycobacteria.…”

“…The high cost of rifapentine, its adverse events and potential difficulties in procuring it may explain these findings. Participants disagreed on whether contacts of patients with MDR-TB should be treated with fluoroquinolones, as recently conditionally recommended by WHO and scientific societies [ 19 , 21 , 33 ]. This is an emerging field, and respondents may not be as familiar with emerging international thought and guidelines, skepticism towards guideline recommendations in the absence of evidence from randomized controlled trials, and concerns about increasing fluoroquinolone resistance in the community by using these drugs as a preventive treatment.…”

“…Traditionally, TB control is aimed at rapidly identifying and treating infectious TB cases [ 11 ] and TB elimination is the strategy aimed at preventing future cases, including diagnosis and treatment of TBI [ 12 , 13 , 14 , 15 , 16 ]. Systematic screening of immigrants from TB high burden settings (by chest radiography—CXR) [ 17 , 18 ], and for TBI is suggested by the World Health Organization (WHO) using one of the two approved tests (tuberculin skin test [TST] or interferon gamma release assays [IGRAs]) [ 19 , 20 , 21 ]. The ECDC (European Centre for Disease Prevention and Control) recommends the use of CXR at arrival in the destination country and TST and/or IGRA for migrants from high-TB-incidence countries [ 22 ].…”

Disease definitions in respiratory and sleep medicine: changes in diagnostic criteria and categories over time and clinical implications

“…Other articles in this issue explore the definitions of pulmonary hypertension, obstructive sleep apnoea, and latent tuberculosis infection [ 5 – 7 ], outlining how these disease labels and categories evolved over time, and how changes in diagnostic criteria impact on clinical practice. The article “Challenging the paradigm: moving from umbrella labels to treatable traits in airway disease” puts forward the idea that umbrella terms such as “asthma” or “COPD” should be replaced by the concept of treatable traits [ 8 ].…”