Late presentation to HIV/AIDS testing, treatment or continued care: Clarifying the use of CD4 evaluation in the consensus definition

Objectives: Late presentation to HIV/AIDS services compromises treatment outcomes and misses opportunities for biomedical and behavioural prevention. There has been significant heterogeneity in how the term 'late presentation' (LP) has been used in the literature. In 2011, a consensus definition was reached using CD4 counts to define and measure late presenters and, while it is useful for clinical care, the consensus definition has several important limitations that we discuss in this article. Methods: Using the spectrum of engagement in HIV care presented by Gardner and colleagues, this article highlights issues and opportunities associated with use of the consensus definition. Results: The consensus definition is limited by three principal factors: (1) the CD4 count threshold of 350cells/μL is being increasingly questioned as the biomedical justification grows for earlier initiation of treatment; (2) CD4 evaluations are conducted at multiple services providing HIV care; thus it remains unclear to which service the patient is presenting late; and (3) the limited availability of CD4 evaluation restricts its use in determining the prevalence of LP in many settings. Conclusions: The consensus definition is useful because it describes the level of disease progression and allows for consistent evaluation of the prevalence and determinants of LP. Suggestions are provided for improving the application of the consensus definition in future research.