Development and validation of a simple and rapid way to generate low volume of plasma to be used in point-of-care HIV virus load technologies.

A new point-of-care HIV viral load, mPIMA HIV-1/2 VL, Abbott, USA, has been recently developed. This point-of-care viral load requires no skilled person to run and uses a small plasma volume (50μL). However, obtaining 50μL of plasma can be a challenge in limited resource settings. We validated a simple and easy method to obtain enough amount of plasma to run a point-of-care viral load. The study utilized 149 specimens from patients failing antiretroviral therapy. At least 250μL of whole blood was collected in a microtube/EDTA from fingerstick (fs-plasma) and immediately centrifuged. Parallel collection of venous blood to obtain plasma (vp-plasma) was used to compare performance in a point-of-care viral load assay and in methodology used in centralized laboratories Abbott M2000, Abbott, USA. The procedure for plasma collection takes less than 10min and in 94% of the cases only one fingerstick was sufficient to collect at least 250μL of blood. The Pearson correlation coefficient value for vp-plasma versus fs-plasma ran on mPIMA was 0.990. The Bland-Altman mean difference (md) for this comparison were virtually zero (md=-0.001) with limits of agreement between -0.225 and 0.223. In addition, the Pearson correlation coefficient value for fs-plasma in mPIMA versus vp-plasma in Abbott M2000 was 0.948 for values above the mPIMA limit of quantification (LoQ; from 800 to 1,000,000copies/mL). These results validate this simple plasma isolation method capable to be implemented in low resource countries where point-of-care decentralization is deeply needed.