12.4 Concomitant treatment TB and HIV

Antiretroviral therapy (ART) dramatically improves survival in HIV-infected patients. In addition, ART reduces TB rates greatly both at individual and population levels.

ART must be initiated in all HIV positive patients with active TB irrespective of the CD4 cell count. Start the anti-TB treatment first, followed by ART as soon as possible and within eight weeks of starting TB treatment1,2,3.

For the following patients, at high risk of mortality, consider starting ART within the first two weeks:
– Patients with low CD4 count (especially CD4 < 50);
– Young children (especially < 1 year of age);
– Patients with drug-resistant TB (DR-TB).

The first-line ART regimen should contain two nucleoside reverse transcriptase inhibitors (NRTIs) plus one non nucleoside reverse transcriptase inhibitor (NNRTI). The preferred NNRTI in patients starting ART while on TB treatment is efavirenz (EFV), since there is less interaction between EFV and rifamycins compared to other NNRTIs. The preferred NRTI in the first-line ART regimen is tenofovir (TDF), combined with either lamivudine (3TC) or emtricitabine (FTC). If TDF is not available, then zidovudine (AZT) is preferred over stavudine (d4T) due to the long-term adverse effects.

In summary, for adults and adolescents:

– Tenofovir/lamivudine/efavirenz (TDF/3TC/EFV) is the preferred first-line ART regimen because of the once daily dosing and the availability of a fixed-dose combination.

– In the event of severe central nervous system intolerance to EFV:
a) Give triple NRTI ART regimen: zidovudine/lamivudine/abacavir (AZT/3TC/ABC);
b) Replace rifampicin (R) with rifabutin (Rfb, 300 mg daily) and start nevirapine (NVP) based ART regimen with lead-in dosing of NVP for 2 weeks;
c) Give NVP based ART regimen tenofovir/lamivudine/nevirapine (TDF/3TC/NVP) but without lead-in dose when used with rifampicin containing first-line TB treatment. In patients with CD4 > 250, close clinical and ALT monitoring at 4, 8 and 12 weeks is recommended.