title: Clinical implications of identifying non-B subtypes of human immunodeficiency virus type 1 infection.
abstract: Although human immunodeficiency virus type 1 (HIV-1) infection in the United States has predominantly involved subtype B, increasing global travel is leading to wider dissemination of genetically heterogeneous subtypes. While physicians depend on HIV-1 viral load measurements to guide antiretroviral therapy, commonly used molecular assays may underestimate the viral load of patients with non-B subtypes. Nine patients with non-B subtypes of HIV-1 were identified by physicians who suspected a non-B subtype on the basis of a low or undetectable HIV-1 viral load, by the Amplicor HIV-1 Monitor test, version 1.0, in conjunction with either a declining CD4 cell count or history of travel outside the United States. Use of version 1.5 of the Amplicor HIV-1 Monitor test detected a median HIV-1 viral load that was 2.0 log(10) RNA copies/mL higher than was determined with version 1.0. Clinical management was altered in all cases after diagnosis of a non-B-subtype infection. These cases demonstrate that it is critical for physicians to suspect and diagnose non-B subtypes of HIV-1 so that an assay with reliable subtype performance can be used to guide antiretroviral therapy.
authors.affiliation: Infectious Diseases Service, Department of Medicine, Wilford Hall Medical Center, Lackland Air Force Base, San Antonio, TX 78236-5300, USA. walter_beth@hotmail.com
authors.forename: E A
authors.initials: EA
authors.lastname: Walter
authors.forename: B
authors.initials: B
authors.lastname: Gilliam
authors.forename: J A
authors.initials: JA
authors.lastname: Delmar
authors.forename: K
authors.initials: K
authors.lastname: Spooner
authors.forename: J T
authors.initials: JT
authors.lastname: Morris
authors.forename: N
authors.initials: N
authors.lastname: Aronson
authors.forename: S A
authors.initials: SA
authors.lastname: Wegner
authors.forename: N L
authors.initials: NL
authors.lastname: Michael
authors.forename: L L
authors.initials: LL
authors.lastname: Jagodzinski
mesh_terms: D000328:Adult; D019380:Anti-HIV Agents / Q000627:therapeutic use; D018791:CD4 Lymphocyte Count; D005500:Follow-Up Studies; D005838:Genotype; D015658:HIV Infections / Q000097:blood / Q000175:diagnosis* / Q000821:virology; D015497:HIV-1 / Q000145:classification / Q000187:drug effects / Q000235:genetics; D006801:Humans; D008297:Male; D008889:Military Personnel; D012367:RNA, Viral / Q000097:blood / Q000187:drug effects; D013997:Time Factors; D019562:Viral Load
chemical_list: D019380:Anti-HIV Agents; D012367:RNA, Viral