title: Therapy failure resulting from superinfection by a drug-resistant HIV variant.
abstract: BACKGROUND
  HIV-1-infected patients can be superinfected with additional HIV-1 variants. Therapy failure can be the consequence of an infection with a resistant strain.
  
  
  METHODS
  A patient was diagnosed with a recent HIV-1 infection in April 2005 and subsequently clinically monitored. HIV-1 evolution was studied by population sequencing of the first 984 bases of the pol gene as well as 454 ultra-deep pyrosequencing (UDPS) of parts of the pol and env genes.
  
  
  RESULTS
  The patient was diagnosed with a wild-type HIV-1 strain, but experienced rapid virological failure after initiating a non-nucleoside reverse transcriptase inhibitor (NNRTI)-based treatment regimen 3 years later. Population sequencing and UDPS revealed the presence of a second HIV-1 strain with a Y188L NNRTI resistance mutation in a sample obtained shortly prior to initiation of therapy. Phylogenetic analyses showed that the two HIV-1 strains were genetically distinct, providing evidence for superinfection.
  
  
  CONCLUSIONS
  The virological treatment failure in this patient was probably due to the superinfection with an NNRTI-resistant HIV-1 variant. Superinfection with drug-resistant strains can undermine HIV-1 treatment regimens selected on the basis of resistance testing at diagnosis. Patients, especially in high-risk groups, as well as their clinicians, should be aware of the risks and dangers of superinfections.
authors: Department of Virology, Erasmus MC, University Medical Center, Rotterdam, the Netherlands.
authors: Marieke
authors: M
authors: Pingen
authors: Jan L
authors: JL
authors: Nouwen
authors: Sander
authors: S
authors: Dinant
authors: Jan
authors: J
authors: Albert
authors: Mattias
authors: M
authors: Mild
authors: Johanna
authors: J
authors: Brodin
authors: Birgitte B
authors: BB
authors: Simen
authors: Susan
authors: S
authors: Walsh
authors: Manfred
authors: M
authors: Kayser
authors: Marchina E
authors: ME
authors: van der Ende
authors: Martin
authors: M
authors: Schutten
authors: Charles A B
authors: CA
authors: Boucher
mesh_terms: D023241:Antiretroviral Therapy, Highly Active; D018791:CD4 Lymphocyte Count; D024882:Drug Resistance, Viral / Q000235:genetics; D015752:Genes, env; D015751:Genes, pol; D005838:Genotype; D015658:HIV Infections / Q000188:drug therapy* / Q000276:immunology / Q000821:virology*; D015497:HIV-1 / Q000235:genetics; D006801:Humans; D009154:Mutation; D010802:Phylogeny; D015163:Superinfection / Q000821:virology*; D017211:Treatment Failure; D019562:Viral Load