There is a difference in the approach on when to start treatment between the UK and US guidelines for treating HIV. In the UK, recent guidelines recommend starting antiretroviral therapy (ART) when the CD4 level falls below 350 (though there are exceptions, where earlier treatment is recommended). Until now, the US guidelines recommended treatment with ARTs when the CD4 count fell below 500. These US guidelines have now been revised.
The newly updated US HIV ART guidelines are recommending ART for all people with HIV, irrespective of CD4 count. There is particular emphasis on treatment for people with CD4 cell counts below 500; anyone at risk of transmitting HIV to partners; pregnant women; and people with hepatitis B co-infection or HIV-related kidney disease.
The reasons for this are complex, and (perhaps as usual) the US is taking a more proactive approach, whereas the UK is awaiting further evidence to show the benefits of such an approach.
The full article can be read here.