Arteriovenous fistulas (AVFs) are uncommon and usually follow trauma or pre
ceding arterial catheterization or puncture. Spontaneous AVFs are rare. A c
ase of spontaneous AVF of the superficial femoral artery and vein in an HIV
-infected patient is presented. Histologic examination of the artery showed
features similar to those seen in HIV-related large-vessel aneurysms. It w
ould appear that spontaneous AVF are part of the spectrum of macrovascular
arteritis related to HIV infection.