Prevention of TB in HIV-infected persons

Infection with HIV is the strongest known risk-factor for the development of tuberculosis. Possible means of intervention include:

• case-finding and treatment
• preventive therapy
• environmental measures

Preventive therapy with isoniazid is now recommended internationally. However, it is not clear that current guidelines are adhered to in developed countries, and they have received limited attention in resource-poor countries.

The optimal drug regimen and duration of therapy have not been clearly established, and the possible emergence of drug resistance is a concern. Active tuberculosis must be excluded before and during the course of preventive therapy, so as to avoid inadequate therapy and the rapid dissemination of drug-resistant strains.

Notes:

• BCG is contraindicated in symptomatic HIV-positive individuals (1). In countries such as the UK where the risk of TB is low, it is recommended that BCG is also withheld from all those known to be or suspected to be HIV positive, regardless of clinical status. Where vaccination is indicated, for example infants born to HIV-positive mothers, this can be administered after two appropriately timed negative postnatal PCR tests for HIV infection.

Reference:

1. Immunisation Against Infectious Disease - "The Green Book".Chapter 32 tuberculosis (January 2016).