Clinical utility of genotyping resistance test on determining the mutation patterns in HIV-1 CRF01_AE and subtype B patients receiving antiretroviral therapy in Hong Kong.
BACKGROUND
HIV-1 genotypic resistance test (GRT) has been widely used to monitor HIV infection but only few reports revealed the mutation patterns of non-B HIV-1 subtypes.


OBJECTIVE
To evaluate the concordance of GRT and clinical treatment outcomes on different HIV-1 subtypes and monitor the mutation patterns and frequencies.


METHODS
Pre- and post-treatment plasma samples from 123 patients (39 treatment naïve and 84 treatment experienced) were tested by ViroSeq HIV-1 Genotyping System followed by analysis using the Stanford HIV database. The mutation patterns and frequencies developed in the pol gene were compared among subtypes.


RESULTS
HIV-1 subtypes among patients in Hong Kong were mainly subtype B and CRF01_AE. Primary mutation was not detected among all pre-treatment samples. For post-treatment samples, primary mutations were only detected in the treatment failure group. The mutation patterns and frequencies were similar between CRF01_AE and subtype B viruses. However, the frequencies of L74V/I and K103N in the reverse transcriptase region were different between CRF01_AE and subtype B viruses. VirtualPhenotype was unable to analyze an in-frame insertion of arginine and isoleucine at protease codon 35 of one CRF01_AE isolate.


CONCLUSIONS
This is the first report to demonstrate the high degree of concordance of longitudinal genotyping data and clinical treatment outcome in patients harboring different HIV-1 subtypes. Our findings shed light to the emergence of resistance mutations and its testing in CRF01_AE, which is relevant to other prevailing places in Asia.
Yam
W C
WC
Department of Microbiology, Queen Mary Hospital, The University of Hong Kong, Hong Kong Special Administrative Region, China. wcyam@hkucc.hku.hk
Chen
J H K
JH
Wong
K H
KH
Chan
K
K
Cheng
V C C
VC
Lam
H Y
HY
Lee
S S
SS
Zheng
B J
BJ
Yuen
K Y
KY
D000465:Algorithms; D023241:Antiretroviral Therapy, Highly Active; D024882:Drug Resistance, Viral / Q000235:genetics*; D015658:HIV Infections / Q000188:drug therapy* / Q000821:virology; D015497:HIV-1 / Q000145:classification* / Q000187:drug effects* / Q000235:genetics; D006723:Hong Kong; D006801:Humans; D008826:Microbial Sensitivity Tests / Q000379:methods; D009154:Mutation; D011933:Reagent Kits, Diagnostic; D017211:Treatment Failure; D016896:Treatment Outcome
D011933:Reagent Kits, Diagnostic