Thank you for your post.
It's clear that this patient is failing antiretroviral therapy. I'm quite concerned that it appears that both the viral load and lack of CD4 count indicate treatment failure, and it's reasonable to assume that this has been going on for some time.
The best second line treatment at this point depends a lot on the local availability of products (ie, are you in the US/Europe or in a resource-limited country). Conventionally, this could involve the use of a tenofovir/3TC or tenofovir/FTC nucleoside combination with a ritonavir-boosted protease inhibitor. Lopinavir/ritonavir (Kaletra) is popularly used in many places, though there is a growing sentiment that better options are available for first line PI use- either the once-daily PIs atazanavir or fosamprenavir. Recently, research data on ritonavir/darunavir suggests that this is superior to Kaletra for persons with high viral loads such as this patient.
If possible, resistance testing would be performed (I would include phenotypic and genotypic testing) to ascertain the extent to which the NRTIs retain activity. If there is significant compromise, then the use of other drug classes, such as CCR5- or integrase inhibitors could be entertained.
I hope this helps,
BY
