Cytomegalovirus Drug Resistance by Next Generation Sequencing, Ganciclovir, Foscarnet, Cidofovir, Maribavir, and Letermovir

This assay assesses resistance to ganciclovir, foscarnet, cidofovir, maribavir, and letermovir. Resistance-associated mutations in the UL97, UL54, UL27, and UL56 genes are sequenced using next generation sequencing. Drug resistance is assigned using an ARUP-developed database of published resistance mutations. For a list of resistance mutations refer to https://ltd.aruplab.com/Tests/Pub/3004615.

This test detects populations down to 10% of the total population which may account for resistance interpretation differences between methods. Some insertions or deletions may be difficult to detect using this software.

Result interpretations are as follows:

* Sensitive indicates no evidence of drug resistance compared with a wild-type virus.
* Possible resistance indicates mutations were detected with borderline-level drug resistance or conflicting resistance status reported in the literature.
* Resistant indicates evidence of drug resistance compared with a wild-type virus.
* Not determined indicates incomplete sequence coverage across a given gene or genes.
* Additional mutations include variants that have not been associated with drug resistance.
* Uncalled mutation sites include drug resistance mutation positions with an inadequate number of sequencing reads.
* Inadequate sequence coverage indicates a low number of sequence reads at a given drug resistance site.

Drugs associated with each gene are as follows:

* UL97: ganciclovir, maribavir
* UL54: ganciclovir, foscarnet, cidofovir
* UL27: maribavir
* UL56: letermovir

This test was developed, and its performance characteristics determined by ARUP Laboratories. It has not been cleared or approved by the U.S. Food and Drug Administration. This test was performed in a CLIA-certified laboratory and is intended for clinical purposes.