Hepatitis B virus – resistance genotyping

Alternative Names/Synonyms	Molecular detection of resistance to nucleotide/nucleoside analogues in Hepatitis B virus
Laboratory	Microbiology
Sub-section	Virology
Specimen Type	○ Serum ○ Plasma

Other Information

○ Testing will only be performed on specimens that are positive for HBV DNA (i.e, detectable viral load)

○ Patient must be on previous or current antiviral therapy for Hepatitis B infection. Individuals currently on therapy must have evidence of antiviral failure or nonresponse. Resistance testing can be performed in the setting of previous antiviral treatment for Hepatitis B to determine subsequent therapies.

Specimen Requirements (Tube Type)

○ Serum: serum separator tube (clotted blood)
○ Plasma: EDTA-blood tube (lavender top)

Collection Requirements

○ Decontaminate skin with 70% alcohol followed by iodine or chlorhexidine, collect at least 5 mL of blood

Sample Stability

Refer to section Sample Processing / Delivery

Referral Laboratory

NML

Routine Turnaround Time

○ Up to 19 days upon receipt by NML

Laboratory Contact Information

416-586-4800 extension 4514

Approval Required

YES

Sample Processing / Delivery

○ Label specimen container. Place specimens in biohazard bag and seal.

○ Specimens should be stored and transported to the UHN/SH Microbiology Laboratory at refrigeration temperature (2-8˚C) immediately after collection

○ UHN/SH Microbiology Laboratory will refer the original positive specimen to the National Microbiology Laboratory for testing upon request