title: Localized cerebral proton MR spectroscopy in HIV infection and AIDS.
abstract: OBJECTIVE
  To document differences in the cerebral proton MR spectra of patients with early and late stages of human immunodeficiency virus (HIV) infection.
  
  
  METHODS
  We studied the relative N-acetyl-aspartate (NAA) levels by localized proton spectroscopy of the parietooccipital region of the brain in 43 HIV-seropositive patients, including 26 with an acquired immunodeficiency syndrome (AIDS)-defining diagnosis, and in eight control subjects.
  
  
  RESULTS
  Reduced relative NAA levels were shown in those HIV-1-seropositive patients: 1) with AIDS against HIV-1-seropositive patients without AIDS (P < .04); 2) with HIV-1-associated cognitive/motor complex against neurologically healthy patients (P < .007); 3) with encephalopathic changes on MR against those with normal imaging (P < .001); and 4) on follow-up against their results on initial study (P < .03).
  
  
  CONCLUSIONS
  By clinical (Centers for Disease Control classification) and radiologic (MR evidence of white-matter disease) criteria indicating late-stage HIV infection, reduced relative levels of NAA have been demonstrated. Spectroscopic abnormalities can be quantitatively tracked with time. This paper demonstrates the clinical use of detecting NAA as a putative in vivo measure of the neuronal loss that has been demonstrated in postmortem studies of patients with AIDS. This neuronal loss, which is believed to underlie the HIV-1-associated cognitive/motor complex, is thought to be attributable directly or indirectly to the presence of HIV in the brain. Proton spectroscopy may serve as a quantitative noninvasive indicator of this aspect of cerebral involvement in HIV disease.
authors.affiliation: MR Unit, Middlesex Hospital, London, England.
authors.forename: W K
authors.initials: WK
authors.lastname: Chong
authors.forename: M
authors.initials: M
authors.lastname: Paley
authors.forename: I D
authors.initials: ID
authors.lastname: Wilkinson
authors.forename: M A
authors.initials: MA
authors.lastname: Hall-Craggs
authors.forename: B
authors.initials: B
authors.lastname: Sweeney
authors.forename: M J
authors.initials: MJ
authors.lastname: Harrison
authors.forename: R F
authors.initials: RF
authors.lastname: Miller
authors.forename: B E
authors.initials: BE
authors.lastname: Kendall
mesh_terms: D015526:AIDS Dementia Complex / Q000378:metabolism; D000386:AIDS-Related Complex / Q000378:metabolism; D000163:Acquired Immunodeficiency Syndrome / Q000378:metabolism*; D000328:Adult; D001224:Aspartic Acid / Q000031:analogs & derivatives / Q000032:analysis; D001923:Brain Chemistry; D002794:Choline / Q000032:analysis; D003401:Creatine / Q000032:analysis; D003937:Diagnosis, Differential; D006679:HIV Seropositivity / Q000378:metabolism*; D006801:Humans; D009682:Magnetic Resonance Spectroscopy; D008875:Middle Aged
chemical_list: D001224:Aspartic Acid; C000179:N-acetylaspartate; D003401:Creatine; D002794:Choline