The pathogenesis of neurologic and neuropsychologic dysfunction in HIV-1 infection is unclear. The purpose of the study was to determine an association between cerebral perfusion and HIV-1-related ocular microangiopathic syndrome.Methods:
We studied 28 HIV-1-infected patients, seven of whom presented with asymptomatic HIV infection, nine with lymphadenopathy syndrome or AIDS-related complex, and 12 with AIDS. Cerebral perfusion was semiquantitatively measured by single photon emission computed tomography of the brain using technetium-99 hexamethyl-propylenamine oxime (HMPAO-SPECT). The conjunctival manifestation of HIV-1-related microangiopathic syndrome was measured by a rating scale determining blood-flow sludging and by counting retinal cotton-wool spots. CD4 count, neopterin, β2-microglobulin (β2M), haemoglobin, and age were determined as putative confounding variables.Results:
Mean conjunctival sludge in patients with normal HMPAO-SPECT findings was 1.3±0.5 (mean±s.e.m.); no cotton-wool spots were present. In patients with slightly impaired HMPAO-SPECT, it was 2.1±0.6 and mean cotton-wool spot count was 1.1±0.4. In patients with severely impaired HMPAO-SPECT, mean conjunctival sludge was 4.5±0.3 and mean cotton-wool spot count was 4.9±1.1 HMPAO-SPECT findings were closely associated with conjunctival sludge (r=0.72; P<0.001) and number of cotton-wool spots (r=0.78; P<0.001), whereas only a slight association with staging of HIV disease was found (P=0.052). Analysis of covariance controlling for CD4 count, neopterin, β2M, age, and haemoglobin demonstrated a significant difference between the three HMPAO-SPECT groups for both the number of cotton-wool spots (P<0.001) and the conjunctival sludge rating (P<0.001).Conclusion:
There was a close association between severity of HIV-1-related ocular microangiopathic syndrome and severity of cerebral hypoperfusion. Microvascular alterations might contribute to the pathogenesis of neurological and neuropsychological symptoms in patients with HIV-1 disease. Furthermore, the conjunctival sludge rating and the number of cotton-wool spots might be appropriate indicators for severity of microvascular changes of the central nervous system.