P-1801. Clinical Evaluation of a Novel, Extraction-free Isothermal Nucleic Acid Amplification Test for the Detection and Differentiation of HSV-1 and HSV-2 from Various Pediatric Sample Sources

TL;DR

A new test for detecting HSV-1 and HSV-2 in children shows high accuracy and could improve diagnosis from various sample types.

Contribution

A novel extraction-free isothermal test for HSV-1 and HSV-2 detection and differentiation in pediatric samples is clinically evaluated.

Findings

The iAMP test showed 100% agreement with the standard test for negative samples and 96% for positive samples.

The test accurately differentiated HSV-1 and HSV-2 in all non-discrepant cases.

Overall agreement between the iAMP and standard test was 99.4% after resolving discrepancies.

Abstract

HSV is a DNA virus that causes various infections in adults and children. While HSV-1 and HSV-2 share a preference for epithelial and neuronal tissues, HSV-1 usually causes cold sores and HSV-2 commonly leads to genital herpes or lesions. It is essential to rapidly and accurately detect and differentiate HSV-1 and -2 from various sample sources, especially from pediatric populations. However, there are significant diagnostic gaps in FDA-approved PCR tests for detection and differentiation of HSV-1 and -2, for example, limited approved sources, false positives and inter-type cross-reactivity. Herein we aimed to perform clinical evaluation of a novel, extraction-free isothermal nucleic acid amplification test (iAMP HSV 1/2, Atila BioSystems) for the detection and differentiation of HSV-1 and -2 from various pediatric sample sources.

Swab samples collected from oral, skin, genital and eye sites of pediatric patients at Children’s National Hospital were detected using iAMP HSV 1/2 Detection Kit and standard-of-care Simplexa HSV 1 & 2 (Diasorin). Positive, negative and overall percentage agreement of iAMP test was determined against Simplexa test. Accuracy of type differentiation of iAMP HSV 1/2 Detection Kit was determined. Discrepant analysis by patient chart review was performed for any samples with discrepant results between both tests.

178 swab samples were collected from pediatric patients aged ranging from 1 month to 19 years. Among 104 Simplexa negative samples, 100.0% (104/104) were tested negative by iAMP test. Among 74 Simplexa positive samples, 96.0% (71/74) were tested positive by iAMP test, with 3 discrepant samples (Simplexa positive but iAMP negative). The accuracy of type differentiation of iAMP test was 100% (71/71) compared to Simplexa test. After discrepancy analysis, final positive, negative and overall percentage agreement of iAMP test were 98.6% (71/72), 100% (106/106), and 99.4% (177/178) compared to Simplexa test.

This study demonstrated excellent clinical performance characteristics of iAMP HSV 1/2 Kit. It is a useful addition to a suite of molecular assays for detection and differentiation of HSV-1 and -2 from various pediatric sample sources and warrants further validation.

All Authors: No reported disclosures