Tuberculosis

In Belgium, fewer than 1,000 cases per year of the active form, which is contagious because it is pulmonary in 75% of cases, are diagnosed and monitored. These forms are most often confirmed bacteriologically following an appropriate clinical assessment carried out in close collaboration with the laboratory. Isolating the organism makes it possible to assess the sensitivity of the Koch bacillus to the various antituberculosis drugs. Patients can often return home quickly, avoiding hospital isolation, which is difficult to organise at a time when there is a shortage of beds related to Covid; however, treatment is lengthy and must be adapted to any resistance (fortunately rare in Belgium). It often needs to be supervised, as perfect adherence is essential to ensure its efficacy and, consequently, patients’ recovery. Toxicities must also be monitored. Fares (French-speaking) and VRGT (Dutch-speaking) carry out this task through the BeltaTBnet programme while keeping the Belgian register up to date. Erasme Hospital is particularly involved in the operation of these non-profit organisations.

In our country, where the eradication of the disease is being targeted in the medium term in accordance with the WHO, it is also important to detect latent forms and treat them so that they do not become reactivated. The aim is to halt the disease cycle. The interpretation of in vivo tests (tuberculin skin test) is complex because of their lack of specificity, while the sensitivity of in vitro assays following stimulation (QuantiFERON), which are now advocated by many, is insufficient.

The people most at risk of developing active tuberculosis from a “dormant” form are immunocompromised individuals and those with recent exposure (conversion of screening tests).

The pneumology department provides care for these individuals, particularly in preparation for immunotherapy (especially biological therapy, for which screening for a latent form is mandatory), in the presence of a disease affecting the body’s defences, or following contact in the workplace (employees referred by the occupational health service).

There are frequent and excellent clinical interactions with the internal medicine department (AIDS reference centre and infectious diseases clinic).

Pulmonary infections caused by atypical mycobacteria (induced by these less virulent environmental organisms) are also part of the specialist expertise provided by the pulmonology department.

They are rarer but very often occur in the context of pre-existing and predisposing pulmonary conditions (COPD, mucoviscidosis, etc.).

Detecting the organism does not make it a pathogen; it is the progression of the lesions attributed to it that determines whether or not to initiate a long and burdensome treatment. Each case must therefore be considered through targeted multidisciplinary discussion.

The disappearance of the mycobacterium does not establish a cure, which is rather a stabilisation. Follow-up is therefore ongoing.