CEREBRAL SINGLE-PHOTON EMISSION COMPUTED-TOMOGRAPHY ABNORMALITIES IN HUMAN-IMMUNODEFICIENCY-VIRUS TYPE 1-INFECTED GAY MEN WITHOUT COGNITIVEIMPAIRMENT

Objective: To determine whether technetium Tc99m exametazime single-ph oton computed emission tomography (SPECT) can distinguish gay human im munodeficiency virus (HIV)-positive subjects, both with and without mi ld cognitive impairment, from gay HIV-negative control subjects. Desig n: Twenty HIV-positive subjects (12 without cognitive impairment and e ight with mild cognitive impairment) and 10 HIV-negative subjects unde rwent neurological, neuropsychological, magnetic resonance imaging, an d technetium Tc99m exametazime SPECT examinations. Setting: Subjects w ere recruited from a natural history study of gay men with HIV infecti on. Patients: Subjects from the cohort who had previously participated in a magnetic resonance imaging study were selected for the SPECT stu dy. Main Outcome Measures: The SPECT scans were rated as abnormal if f ocal defects, confirmed by a horizontal profile analysis, were seen. R esults: Sixty-seven percent of HIV-positive subjects without cognitive impairment, 88% of HIV-positive subjects with mild cognitive impairme nt, and 20% of HIV-negative subjects had abnormal SPECT scans (P<.05 f or both HIV-positive groups when each group was compared with HIV-nega tive subjects). Conclusion: Compared with gay HIV-negative control sub jects, focal SPECT defects are seen with an increased frequency in HIV -positive gay men without cognitive impairment and in HIV-positive gay men with mild cognitive impairment.