Evaluation of an automated system for the quantitation of human Herpesvirus-6 DNA from clinical specimens

Jordan Mah; ChunHong Huang; Malaya K Sahoo; Benjamin A Pinsky

doi:10.1016/j.plabm.2023.e00329

Evaluation of an automated system for the quantitation of human Herpesvirus-6 DNA from clinical specimens

Pract Lab Med. 2023 Aug 5:36:e00329. doi: 10.1016/j.plabm.2023.e00329. eCollection 2023 Aug.

Authors

Jordan Mah¹, ChunHong Huang¹, Malaya K Sahoo¹, Benjamin A Pinsky^{1

2}

Affiliations

¹ Department of Pathology, Stanford University School of Medicine, Stanford, CA, USA.
² Department of Medicine, Division of Infectious Diseases and Geographic Medicine, Stanford University School of Medicine, Stanford, CA, USA.

Abstract

Background: Quantitation of human herpesvirus-6 (HHV-6) DNA in clinical specimens is important for the diagnosis and management of HHV-6-associated infection and reactivation in immunocompromised patients, particularly transplant recipients.

Methods: The analytical performance of the Altona RealStar ASR HHV-6 qPCR on the semi-automated AltoStar AM16 system was assessed using HHV-6 reference material in plasma and cerebral spinal fluid (CSF). Qualitative and quantitative agreement was determined using 123 clinical EDTA plasma specimens tested using a laboratory-developed HHV-6 qPCR.

Results: The 95% Lower Limit of Detection was 20 IU/mL [95% confidence interval (CI): 10 to 29] in plasma and 78 IU/mL (95% CI: 55 to 146) in CSF. The assay was linear from 7.0 to 2.0 log₁₀ IU/mL in both matrices. Overall agreement of the RealStar ASR HHV-6 qPCR on the AltoStar AM16 with a laboratory-developed test was 95.9% (95% CI: 90.8 to 98.7). Passing-Bablok analysis of specimens quantifiable by both methods and at levels >1000 copies/mL revealed a regression line of Y = 1.00*X-0.20, with neither systematic (95% CI Y-intercept: -0.66 to 0.26) nor proportional (95% CI slope: 0.89 to 1.10) bias compared to the reference.

Conclusions: The RealStar ASR HHV-6 qPCR on the AltoStar AM16 provides accurate quantitation for clinical monitoring of HHV-6 in immunocompromised hosts.