Vitamin A status in relation to electroretinographic and electrooculographic findings in HIV infection.
OBJECTIVE
To investigate the electrooculogram (EOG) and an expanded battery of electroretinograms (ERGs) in HIV-infected subjects without retinopathy at two different levels of immunosuppression. Consideration was given to the possible effects of serum levels of vitamin A.


METHODS
Two groups of neurologically normal HIV-positive subjects with CD4+ cell counts of <200 (n=17) or >400 (n=19) were contrasted with 20 HIV-negative controls. Rod ERGs, oscillatory potentials and cone ERGs were obtained using ganzfeld stimulation. A sequence of dark- and light-adapted EOG recordings was analyzed to obtain light/dark ratios. The HIV-positive subjects underwent a comprehensive ophthalmologic examination.


RESULTS
Intergroup comparisons failed to reveal any significant intergroup differences. Abnormal ERG findings, those exceeding the 98% confidence limits, occurred in 11% (4/36) of the HIV-positive subjects. One of these subjects was hyporetinemic and another had a subnormal retinol level. No subjects had abnormal EOGs.


CONCLUSIONS
HIV infection influenced retinal function in 11% of a group of neurologically normal subjects without clinical signs of retinopathy. The profile of electrophysiological findings suggested predominant functional deficits involving middle or inner retinal layers. Vitamin A deficiency and possible vascular changes could account for the observed ERG abnormalities.
Bartel
P
P
Department of Neurology, Pretoria Academic Hospital and University of Pretoria, Pretoria, South Africa. pbartel@medic.up.ac.za
Roux
P
P
van Niekerk
M
M
D000293:Adolescent; D000328:Adult; D001683:Biological Clocks; D018791:CD4 Lymphocyte Count; D002851:Chromatography, High Pressure Liquid; D004585:Electrooculography; D004596:Electroretinography; D005128:Eye Diseases / Q000097:blood / Q000175:diagnosis* / Q000209:etiology*; D005260:Female; D015658:HIV Infections / Q000097:blood* / Q000150:complications*; D018023:HIV Seronegativity / Q000502:physiology; D006679:HIV Seropositivity / Q000097:blood; D006801:Humans; D008297:Male; D008875:Middle Aged; D017949:Retinal Cone Photoreceptor Cells; D014801:Vitamin A / Q000097:blood*
D014801:Vitamin A