Acta Neurol Scand 1996: 93: 266-271 Printed zyxwvutsrqpon in UK zyxwvutsrqponm - zyxwvutsr all rights reserved Copyright zyx 0 Munksgaard 1996 zy ACTA NEUROLOGICA SCANDINAVICA ISSN 0001 -6314 Multimodal evoked potentials in HIV- 1 - seropositive patients: relationship between the immune impairment and the neurophysiological function Pierelli F, Garrubba C, Tilia G, Parisi L, Fattapposta F, Pozzessere zyxwv G, Soldati G, Stanzione P, D’Ofii G, Mezzaroma I. Multimodal evoked potentials in HIV-1-seropositive patients: relationship between the immune impairment and the neurophysiological function. Acta Neurol Scand 1996: 93: 266-271. 0 Munksgaard 1996. Multimodal evoked potentials (PRVEP, BAEP, mSEP) were recorded in 56 HIV-1 seropositive outpatients free from opportunistic CNS pathologies and/or overt HIV-1 encephalopathy. EPs were altered in 17 of 39 (43.6%) seropositive subjects without AIDS (group A) and in 13 of 17 (76.5%) patients with AIDS (group B). A high incidence of subclinical alterations (30.8%) were found in group A patients. Significant BAEP zyxw (1-111, zyxwvutsr 111-V, I-V) interpeak latency and mSEP (N9-Nl3, N9-N20) conduction time prolongations were found in group A and B patients. PRVEP PlOO was significantly prolonged only in group B. An inverse relationship between BAEP interpeak latencies and CD4 count was found. Our findings support the hypothesis of an important role of immunodepression in the development of neurophysiologic abnormalities, together with a preferential involvement of acoustic pathways, in the course of HIV-1 infection. After systemic infection, the human immunodefici- ency virus (HIV) rapidly spreads into the central nervous system (CNS). This assumption is sup- ported by the possible occurrence of an acute aseptic meningitis coincidental with seroconversion ( 1, 2) and by the results of several studies performed on the cerebrospinal fluid (CSF) of asymptomatic sub- jects during the early phases of the infection (3-7). CNS pathologies in HIV infected subjects may be represented by opportunistic infections, lymphomas and Kaposi’s sarcoma as a consequence of the immune suppression. One of the most common clinical complications, however, consists of cognit- ive and motor changes of various degree, for which a clear histopathologic substrate has not been identi- fied yet. This clinical syndrome, called HIV-1 associ- ated cognitive-motor complex, includes two main categories: the milder form, “HIV- 1 associated minor cognitive-motor disorder”, and the more severe form, “HIV- 1 associated dementia com- plex” (8). Although a clinically evident encephalopathic F. Pierelli ’, C. Garrubba ‘, G. Tilia ’, 1. Parisi ’, F. Faltapposta ’, G. Pozzessere ‘, G. Soldati *, P. Stanzione ’, G. D’Offizi ‘, 1. Mezzaroma ‘ ’Istituto di Clinica delle Malattie Nervose zyx e Mentali. Universita “La Sapienza”. ’lstituto Mediterraneo di Neuroscienze “Sanatrix”. IRCCS, Pozzilli (IS). Unica Neurologica. Universita “Tor Vergata”, 41~tit~t~ di lmmunologia e Allergologia, Dipartimento di Clinica Medica. Universita “La Sapienza”. Roma Key words: HIV-1 infection, AIDS; Evoked Potentials (W); CD4 Francesco Pierelli. lstituto di Clinica delle Malattie Nervose e Mentali, Universita degli Studi di Roma ”La Sapienza“, Viale dell’llniversita, 30. 00185 Roma, ltalia Accepted for publication November 15. 1995 syndrome may be observed in the majority (70%) of AIDS patients at some point of the disease (9), the onset of this syndrome during the pre-AIDS stage may be delayed for years and is rather subtle in its clinical course. Since it has been observed that CSF examination and Magnetic Resonance Imaging (MRI) allow to document early CNS anomalies but do not provide reliable predictive elements as regards the temporal progression of the encephalo- pathy (4, 10, 11), a series of studies have been performed with the aim of investigating the re- liability of various electrophysiological tests in the assessment of its prevalence and course. Evoked potentials ( EPs) recording has been widely employed in several neurologic diseases as a reliable tool in detecting white matter lesions during a preclinical phase (12-14). The application of this method to the study of HIV-1 seropositive patients has evidenced a high degree of electrophysiological abnormalities in patients with full blown AIDS ( 15- 17) and a variable degree of subclinical anomal- ies in neurologically asymptomatic HIV- 1 -seroposi- 266