Starting anti-HIV treatment within two weeks of the diagnosis of tuberculosis improved survival among patients with both infections who had very low immune-cell counts, a new study has found.
Those with strong immune systems, however, might benefit from waiting until after the end of the six-month TB treatment before initiating anti-HIV therapy, researchers found.
Infection with HIV can promote progression and re-infection to active TB after initial exposure to Mycobacterium tuberculosis, the organism that causes TB, said senior author Jean B Nachega, associate professor at University of Pittsburgh Graduate School Of Public Health.
Treating HIV and TB simultaneously is challenging for many reasons, including the requirement for patients to take multiple pills several times daily for each infection, drug-drug interactions and overlapping side effects.
"Current World Health Organisation guidelines recommend starting TB treatment first, followed by HIV treatment as soon as possible within two to eight weeks for patients who have moderately to severely compromised immune systems, but there was not conclusive evidence to guide treatment in other levels of immune suppression," Nachega said.
"We aimed to investigate the optimal timing of HIV initiation in light of recent published randomised clinical trials on this topic," he said.
The team reviewed data from more than 4,500 people participating in eight randomised clinical trials of early initiation of HIV anti-retroviral therapy (ART) conducted in Asia, Africa and the US.
They found that survival rates were better among patients who started ART within two weeks of the initiation of TB treatment and who also had very low CD4 T-cell counts of less than 0.050 x 109 cells per litre, as measured by a blood test which reflects severe immune system suppression due to HIV.
Early initiation was also associated with double increase in frequency of a complication called TB-Immune Reconstitution Inflammatory Syndrome, which can be fatal in rare occasions.
"Our findings support guidelines recommending early initiation of ART in patients with a high degree of immune system compromise," Nachega said.
"But delaying ART might be possible until the end of TB treatment with patients with CD4 counts greater than 0.220 x 109cells per litre, which could reduce the burden of taking two complex drug regimens at the same time," he said.
The study was published in the journal Annals of Internal Medicine.
