Preferred Sample Type
Suitable Specimen Types
- EDTA Whole Blood
Turnaround Time
14 daysSample Stability
Freshly drawn specimens (whole blood) may be held at 2 to 30°C for up to 6 hoursprior to centrifugation. Plasma samples are stored for 2 years at -20°C.
Cytomegalovirus (CMV) UL97 genotypic resistance
General Information
Genotypic resistance data provides information on the presence/absence of drug resistance mutations, which is used as a predictor of virological response to therapy. This aids clinical decisions regarding therapy changes. Choosing the most appropriate therapy regime improves patient management and reduces the cost of care.
The assay is an in-house genotypic assay for the detection of CMV resistance to ganciclovir treatment. The current anti-CMV drugs – ganciclovir (GCV) and its prodrug valganciclovir, foscarnet and cidofovir all target the viral DNA polymerase. Resistance testing is based on the detection of mutations in the viral UL97 kinase and UL54 DNA polymerase genes. The resistance test we perform will detect mutations in the UL97 region of the genome which confer resistance to ganciclovir. GCV requires three phoshorylation steps for its antiviral activity. The UL97 kinase performs the initial phosphorylation.
The methodology for CMV resistance testing of the UL97 region involves extraction of DNA , CMV PCR, population sequencing and sequence analysis.
Patient Preparation
For taking blood samples we recommend that users follow either their local protocols or “The Royal Marsden Manual of Clinical Nursing Procedures”.
Lavender top blood (EDTA) sample
- Sufficient blood for the test should be drawn into lavender topped (EDTA) vacuum tubes
- Invert tube 8–10 times.
The UL97 genotypic resistance request form is available from the following link UL97 REQUEST FORM
Specifications
- EQA Scheme?: Yes
- EQA Status: QCMD scheme