Prevalence of drug-resistant HIV-1 variants in untreated individuals in Europe: implications for clinical management.
BACKGROUND
Infection with drug-resistant human immunodeficiency virus type 1 (HIV-1) can impair the response to combination therapy. Widespread transmission of drug-resistant variants has the disturbing potential of limiting future therapy options and affecting the efficacy of postexposure prophylaxis.


METHODS
We determined the baseline rate of drug resistance in 2208 therapy-naive patients recently and chronically infected with HIV-1 from 19 European countries during 1996-2002.


RESULTS
In Europe, 1 of 10 antiretroviral-naive patients carried viruses with > or = 1 drug-resistance mutation. Recently infected patients harbored resistant variants more often than did chronically infected patients (13.5% vs. 8.7%; P=.006). Non-B viruses (30%) less frequently carried resistance mutations than did subtype B viruses (4.8% vs. 12.9%; P<.01). Baseline resistance increased over time in newly diagnosed cases of non-B infection: from 2.0% (1/49) in 1996-1998 to 8.2% (16/194) in 2000-2001.


CONCLUSIONS
Drug-resistant variants are frequently present in both recently and chronically infected therapy-naive patients. Drug-resistant variants are most commonly seen in patients infected with subtype B virus, probably because of longer exposure of these viruses to drugs. However, an increase in baseline resistance in non-B viruses is observed. These data argue for testing all drug-naive patients and are of relevance when guidelines for management of postexposure prophylaxis and first-line therapy are updated.
Wensing
Annemarie M J
AM
Eijkman Winkler Institute, Department of Virology, University Medical Center Utrecht, The Netherlands.
van de Vijver
David A
DA
Angarano
Gioacchino
G
Asjö
Birgitta
B
Balotta
Claudia
C
Boeri
Enzo
E
Camacho
Ricardo
R
Chaix
Maire-Laure
ML
Costagliola
Dominique
D
De Luca
Andrea
A
Derdelinckx
Inge
I
Grossman
Zehava
Z
Hamouda
Osamah
O
Hatzakis
Angelos
A
Hemmer
Robert
R
Hoepelman
Andy
A
Horban
Andrzej
A
Korn
Klaus
K
Kücherer
Claudia
C
Leitner
Thomas
T
Loveday
Clive
C
MacRae
Eilidh
E
Maljkovic
Irina
I
de Mendoza
Carmen
C
Meyer
Laurence
L
Nielsen
Claus
C
Op de Coul
Eline L
EL
Ormaasen
Vidar
V
Paraskevis
Dimitris
D
Perrin
Luc
L
Puchhammer-Stöckl
Elisabeth
E
Ruiz
Lidia
L
Salminen
Mika
M
Schmit
Jean-Claude
JC
Schneider
Francois
F
Schuurman
Rob
R
Soriano
Vincent
V
Stanczak
Grzegorz
G
Stanojevic
Maja
M
Vandamme
Anne-Mieke
AM
Van Laethem
Kristel
K
Violin
Michela
M
Wilbe
Karin
K
Yerly
Sabine
S
Zazzi
Maurizio
M
Boucher
Charles A
CA
D000328:Adult; D019943:Amino Acid Substitution; D024882:Drug Resistance, Viral / Q000235:genetics*; D005060:Europe; D005260:Female; D015658:HIV Infections / Q000188:drug therapy / Q000821:virology*; D015497:HIV-1 / Q000187:drug effects* / Q000235:genetics; D006801:Humans; D008297:Male; D020125:Mutation, Missense