Endothelin-1 is elevated in the cerebrospinal fluid of HIV-infected patients with encephalopathy

In a cross-sectional, non-randomized, prospective study in an outpatient cl inic a possible relationship between the cerebrospinal fluid (CSF) concentr ations of the potent vasoconstrictor peptide endothelin-1 (ET-1) and preval ence a nd degree of HIV-encephalopathy was stud led. Forty-eight CSF sample s from HIV-infected patients undergoing lumbar punction for diagnostic reas ons were investigated for ET-1 concentrations. in 37 patients ET-1 was also measured in plasma. Patients were investigated clinically and staged with respect to HIV encephalopathy. Patients with arterial hypertension, diabete s or acute opportunistic infections were excluded from the study. In the re maining, 18 of the CSF samples were from patients with normal neurological findings (grade 0-0.5), whereas 30 were from patients with HIV encephalopat hy (grade 1-3) The mean CSF ET-1 concentration was significantly elevated ( P = 0.001) in patients with HIV encephalopathy (1.97 +/- 2.33 pmol/l) as co m pa red to those patients without encephalopathy (0.57 +/- 0.67 pmol/l). M oreover, there was a significant correlation between ET-I CSF concentration s and the degree of HIV encephalopathy (r = 0.49, P < 0.001). In addition, there was a significant correlation between ET-1 revels in the CSF and the IgG serum to CSF ratio. However, we found no correlation between HIV enceph alopathy and neither CSF total protein, IgG, albumin or the serum to CSF ra tio of IgG or albumin. In conclusion, we could demonstrate a close relation ship between CSF ET-1 concentrations and the degree of HIV encephalopathy. Thus, by virtue of its long-lasting and potent vasoconstrictor activity ET- 1 might contribute to the pathogenesis of HIV encephalopathy.