Static and dynamic posturography in patients with asymptomatic HIV-1 infection and AIDS

Alterations of the vestibulo-ocular reflex, optokinetic nystagmus, and visuo-vestibular-ocular reflex, have already been described in patients with AIDS and HIV-1 positive asymptomatic subjects. The introduction to the clinical practice of posturographic techniques allows us to study, with precision, postural perturbation that may be present when performing Romberg's test and to study the vestibulo-spinal reflex as a component of the vestibular system. The relative lack of studies on posturography and AIDS, encouraged us to continue our research on the vestibular system both in asymptomatic HIV-1 seropositive patients and in patients with AIDS (IV stage according to the classification proposed by the Centre for Disease Control). Recordings were made in group 1 (control group, 55 normal subjects), in group 2 (15 asymptomatic HIV-positive subjects), and in group 3 (15 patients with AIDS stage IV). Static and dynamic posturography were carried out using Tonnies platform system (Tonnies GmbH & Co., Wurzburg, Germany) and the data were analysed with Tonnies Posturographic Tübingen (TPOST) software vers. 5.19. In asymptomatic HIV+ subjects, we observed an increase in RW, RA and M3 reflex latency. AIDS patients (stage IV) exhibited significant alterations in almost all the posturographic parameters and the electromyographic potentials. Our results validate static and dynamic posturography as a method for otoneurological investigation and appear to confirm that the entire vestibular system is involved since the earliest stages of the HIV infection. In the HIV+ subjects, a variable dysfunction in the reflex control to long latency was observed, which is correlated with the alteration of the central dopaminergic system; in AIDS patients, the central nervous system damage appears more important, globally distributed and correlated also with immunosuppression.