Accuracy of plasma HIV RNA quantification: a multicentre study of variability

Area of Science:

• Virology
• Clinical Diagnostics
• Public Health

Background:

• Accurate quantification of plasma human immunodeficiency virus (HIV) RNA concentration is critical for patient care.
• Limited data exists on the reproducibility of HIV RNA quantification within and between clinical laboratories.

Purpose of the Study:

• To assess the reproducibility of plasma HIV RNA concentration measurements across multiple laboratories and assay kits.
• To identify factors influencing variability in HIV RNA quantification.

Main Methods:

• Weekly distribution of identical plasma specimens to 13 laboratories over 13 weeks (January-April 1998).
• Laboratories performed HIV RNA quantification using their routine methods and reported results.
• Analysis of inter-laboratory and inter-assay kit correlation and reproducibility.

Main Results:

• Generally satisfactory correlation of results between laboratories and assay kits.
• HIV RNA concentrations varied by assay kit, with Roche Monitor and AcuGen higher and Chiron Quantiplex v 2.0 lower than average.
• Chiron Quantiplex v 2.0 demonstrated the highest reproducibility; nine 'below detection limit' results were associated with three specimens, including one with HIV-1 clade G RNA.

Conclusions:

• An unsustained change in HIV RNA of
• Performance assessment and conservative interpretation of isolated HIV RNA changes are necessary.
• Parallel testing of consecutive patient specimens offers the most reliable indication of significant HIV RNA concentration change.