Human immunodeficiency virus infection unresponsive to highly active antiretroviral therapy: Denial of poor medication adherence or recalcitrant infection?

Poor clinical and virologic response to combination antiretroviral therapy for human immunodeficiency virus (HIV) infection may stem from a variety of factors including poor medication adherence, development of drug-resistant HIV strains, drug interactions, efflux pumps, and unfavorable pharmacokinetics. Diagnosing nonadherence to medication is particularly challenging. We present a case of lack of response to antiretroviral therapy in a patient who denied problems with medication adherence. The patient underwent a variety of objective examinations, all of which suggested poor medication adherence was responsible for his non-response to antiretrovirals. An approach to evaluating patients for causes of poor response to antiretroviral therapy and nonadherence and implications for clinical practice are discussed.