METHODS FOR DETECTING EARLY SIGNS OF AIDS DEMENTIA COMPLEX IN ASYMPTOMATIC HIV-1-INFECTED SUBJECTS

Objectives: To determine the optimal diagnostic procedures for identifying early signs of AIDS dementia complex (ADC) in asymptomatic HIV-1-infected individuals, in order to prevent further cognitive function impairment by early treatment. Design: Study patients had been referred electively and consecutively to hospital; all had been referred for the first time and gave informed consent. Inclusion criteria were (1) lack of history and/or symptoms of psychosis and neurological disorders; (2) lack of active viral, protozoan or fungal pathology; (3) abstinence from heroin and/or cocaine for at least 6 months before baseline evaluation. Setting: Subjects were seen at the L. Spallanzani Hospital for Infectious Diseases, Rome, Italy between March 1989 and March 1991. Participants: Eighty-two asymptomatic HIV-1-infected subjects: 41 drug users, 27 homosexuals and 14 heterosexuals. Main outcome measures: All subjects were evaluated using Wechsler-Bellevue 1, Benton C form and Bender tests. Thirty-nine subjects underwent single-photon emission computed tomography (SPECT) and 12 magnetic resonance imaging (MRI). The immunological status of each subject was determined. Results: On psychometric testing, 23 out of the 82 (28%) asymptomatic subjects had a mental decay percentage (MD%) greater-than-or-equal-to 20%. Cerebral perfusion abnormalities were detected in 31 out of 39 (79.48%) subjects who underwent SPECT; MRI abnormalities were observed in seven out of 12 (58%) subjects. Twelve out of 23 subjects with MD% greater-than-or-equal-to 20, 15 out of 29 subjects with SPECT abnormalities and four out of seven patients with MRI abnormalities had total CD4 + lymphocyte counts greater-than-or-equal-to 500 x 10(6)/l. Conclusions: The high incidence of abnormal SPECT and of MD% greater-than-or-equal-to 20 in asymptomatic HIV-1-infected patients, and the lack of correlation between immunological status and degree of mental decay, SPECT and MRI abnormalities raise many questions about subclinical HIV-1 neurological disease.