[Primary isoniazid preventive therapy : A strategy still relevant in the era of test and treat ; literature review]. / Chimioprophylaxie antituberculeuse primaire à l'isoniazide : une stratégie d'actualité à l'ère du tester et traiter ; revue de la littérature.

BACKGROUND: Tuberculosis remains a public health threat responsible as recently as 2018 for more than one million deaths. Chemoprophylaxis with isoniazid is one of the strategies implemented to control the disease. Although it is not yet widely prescribed, its utilization raises additional questions in the "test and treat" era of for anti-retroviral therapy. The objective of this study is to review the different randomized controlled trials of antitubercular Isoniazid Preventive Therapy (IPT). We have distinguished (a) "efficacy trials" (ET) comparing IPT to a placebo or the absence of chemoprophylaxis and (b) "IPT regimen trials" (RT) comparing IPT to one or several other regimens. METHODS: Literature search (keywords from published articles found in the Medline and Scopus data bases: "tuberculosis", "prophylaxis", "HIV", "randomized controlled trial") and standardized reading of selected articles reporting results from randomized trials of IPT in HIV-infected people. RESULTS: Eighteen selected trials (11 ET and 7 RT), including 19,725 participants. The regimens studied were 3H, 6H, 9H, 12H, 12H, 36H/2RZ, 3RH, 3RZ, 3RHZ, and 3HP [H: Isoniazid, R: Rifampicin, Z: Pyrazinamide, P: Rifapentine]. LOCATIONS: Ten in Africa, three in Haiti, one in India, one in the USA, one in the Americas and two multi-continental trials. In ET with or without antiretrovirals (ART), IPT significantly reduces the risk of tuberculosis, by 32 to 71%. In ET prior to ART, IPT does not appear to reduce mortality. In ET in patients receiving ART, on the other hand, IPT reduces mortality. As regards RT, there seems to be no reason to prefer other regimens to IPT. Tolerance is good. Importantly, IPT may reduce (rather than worsen) the risk of multidrug-resistant bacilli selection by decreasing the number of TB episodes and, consequently, the number of curative tuberculosis treatments. CONCLUSION: Far from becoming obsolete due to ARV treatment, IPT has remained a timely and relevant intervention.

Screening for active tuberculosis before isoniazid preventive therapy among HIV-infected West African adults.

SETTING: TEMPRANO was a multicentre, open-label trial in which human immunodeficiency virus (HIV) infected adults with high CD4 counts were randomised into early or deferred antiretroviral therapy (ART) arms with or without 6-month isoniazid preventive therapy (IPT) in a setting where the World Health Organization (WHO) recommends IPT in HIV-infected patients. Despite the WHO recommendation, IPT coverage remains low due to fear of the presence of undiagnosed active TB before prescribing IPT, and the related risk of drug resistance. OBJECTIVE: To report the frequency of undiagnosed TB in patients enrolled for IPT and describe the results of a 1-month buffer period to avoid prescribing IPT for active TB cases. DESIGN: Patients were screened using a clinical algorithm and chest X-ray at Day 0 and started on isoniazid at Month 1 if no sign/symptom suggestive of TB appeared between Day 0 and Month 1. RESULTS: Of 1030 patients randomised into IPT arms. 10% never started IPT at Month 1. Of these, 23 had active TB, including 16 with prevalent TB. Among the 927 patients who started IPT, 6 had active TB, including 1 with prevalent TB. Only 1 patient with active TB received IPT due to the 1-month buffer period between Day 0 and IPT initiation. CONCLUSION: In this study, 1.6% of adults considered free of active TB based on clinical screening at pre-inclusion actually had active TB.