Challenges for Rapid Molecular HIV Diagnostics

Abstract

The introduction of serological point-of-care (POC) assays 10 years ago dramatically changed the way HIV infections were identified and diagnosed. Testing at the POC has lead to a dramatic increase in the number of individuals who are screened and, most importantly, receive their HIV test result. As the AIDS epidemic continues to mature and scientific advances in prevention and treatment are evaluated and implemented, there is a need to identify acute (viremic pre-seroconversion) infections and to discriminate “window phase” infections from those that are serologically positive, especially in resource limited settings (RLS), where the majority of the world’s vulnerable populations reside and where the HIV incidence is highest. Rapid testing methods are now at a crossroad. There is opportunity to implement and evaluate the incremental diagnostic utility of new test modalities that are based on sophisticated molecular diagnostic technologies and which can be performed in settings where laboratory infrastructure is minimal. The way forward requires sound scientific judgment, as well as an ability to further develop and implement these tests despite a variety of technical, social and operational hurdles to declare success.

Taxonomy of Challenges in Medical Laboratory Diagnostic Services

“…In India, Kapil (2013) raised the issue of implementation of many quality assurance guidelines by the MDLS owing to challenges related to time, complexity and cost (Kapil 2013). In use of RNA testing of dried blood spots for HIV detection, laboratories were unable to communicate consistently and quickly the outcome of the tests to the initial collection points (Schito et al 2010). Patient safety related challenges are associated with the potential side-effect of the use of laboratory services.…”

Clinical Versus Rapid Molecular HIV Diagnosis in Hospitalized African Infants

“…Both tests have limited availability and slow result turnaround time throughout Africa. 7,8 These missed diagnostic opportunities contribute to high mortality rates for HIV-infected African infants. 4 …”

“…7 Such a point-of-care test could eliminate many of the DNA PCR system barriers, so practitioners could expediently determine an infant’s HIV status and start ART before hospital discharge. The World Health Organization (WHO) clinical algorithm for identifying symptomatic HIV-infected infants could meet these needs.…”

“…However, it has not been widely implemented due to performance concerns, 5,14–17 and its key clinical endpoints including ART initiation have not been rigorously studied. While preliminary studies with recently-developed molecular point-of-care infant HIV tests suggest that their sensitivity and specificity profiles will outperform the WHO algorithm, 7 at this time the clinical implications of a point-of-care infant HIV test have not been thoroughly investigated.…”

Performance of a parallel diagnostic algorithm for HIV diagnosis in low risk pediatric and obstetric patient populations

“…Additionally, the frequent indeterminate results from the HIV-1 WB and the inability to differentiate HIV-1 from HIV-2 infections results in delays in confirmation, and may result in delays in the appropriate initiation of therapy for a significant number of patients [11,12]. Furthermore, supplementary confirmatory tests are not only complex and time consuming, but also expensive and subject to shortages [12][13][14][15].…”