Debunking the myths perpetuating low implementation of isoniazid preventive therapy amongst human immunodeficiency virus-infected persons

Abstract

Isoniazid preventive therapy (IPT) is the administration of isoniazid (INH) to people with latent tuberculosis (TB) infection (LTBI) to prevent progression to active TB disease. Despite being life-saving for human immunodeficiency virus (HIV)-infected persons who do not have active TB, IPT is poorly implemented globally due to misconceptions shared by healthcare providers and policy makers. However, amongst HIV-infected patients especially those living in resource-limited settings with a high burden of TB, available evidence speaks for IPT: Among HIV-infected persons, active TB- the major contraindication to IPT, can be excluded with symptom screening; chest X-ray and tuberculin skin testing are unreliable and often lead to logistic delays resulting in increased numbers of people with LTBI progressing to active TB; the use of IPT has not been found to increase the risk of the development of INH mono-resistance; IPT is cost-effective and cheaper than the cost of treating cases of active TB that would develop without IPT; ART and IPT have an additive effect on the prevention of TB, and both are safe and beneficial even in children. In order to sustain the recorded gains from ART scale-up and to further reduce TB-related morbidity and mortality, more efforts are needed to scale-up IPT implementation globally.

Implementation of isoniazid preventive therapy in people living with HIV in Zambia: challenges and lessons

“…The challenges observed in Zambia are not unique to it as they have been observed in other settings [12, 13]. The solutions can hence be applied or adapted to various settings.…”

“…In a file review conducted by the Pharmacy department of CIDRZ only 56 (50%) of the 113 eligible patients had IPT prescribed and only 37(66%) of the 56 that had a prescription received IPT (Unpublished observation). Fears and misconceptions among health workers in other parts of the world have also been observed in Zambia [12]. The commonest fears are: 1) use of IPT promotes isoniazid mono-resistance since symptom screening alone is not sufficient to rule out active TB, 2) the protective effect of IPT is minimized due to ongoing exposure to TB since Zambia is a high burden country 3) increased risk of side effects among PLHIV.…”

Survival of HIV-1 vertically infected children

“…Although WHO has recommended pre-exposure IPT since 2004, coverage remains disappointingly low [95]. Barriers to IPT implementation include exaggerated fear of resistance development [130], unavailability of single entity isoniazid formulations in RLS and concerns about increased pill burden affecting cART adherence [131]. A scored fixed dose combination of isoniazid, vitamin B6 and co-trimoxazole was highly acceptable to adults and children >5 years in the REALITY trial [132] and could help overcome universal IPT implementation barriers; a half-strength scored dispersible tablet is needed for younger children.…”

Tolerability of Isoniazid Preventive Therapy in an HIV-Infected Cohort of Paediatric and Adolescent Patients on Antiretroviral Therapy from a Resource-Limited Setting: A Retrospective Cohort Study

“…In general, isoniazid therapy is recommended for 6–12 months [ 2 ], with an efficacy of approximately 90% among patients who complete treatment [ 3 ]. However, there are concerns regarding the use of isoniazid due to the potential for hepatotoxicity, ranging from asymptomatic elevation of liver enzymes to severe hepatitis [ 4 ]. Isoniazid is a potentially hepatotoxic medicine and its use as an agent for IPT could result in liver toxicities.…”