Detection of varicella zoster virus antigen and DNA in two cases of cerebral amyloid angiopathy

Abstract Objective Varicella zoster virus (VZV) vasculopathy and cerebral amyloid angiopathy (CAA) have similar clinical presentations: both affect cerebrovasculature in the elderly, produce hemorrhage, and can have a protracted course of cognitive decline and other neurological deficits. The cause of CAA is unknown, but amyloid-beta (Aβ) is found within arterial walls. Recent studies show that VZV induces Aβ and amylin expression and an amyloid-promoting environment. Thus, we determined if VZV was present in CAA-affected arteries. Methods Two subjects with pathologically-verified CAA were identified postmortem and frontal lobes analyzed by immunohistochemistry for arteries containing VZV, Aβ, and amylin and HE VZV antigen co-localized with Aβ in media of arteries with histological changes characteristic of CAA. Amylin was also seen in the intima of a VZV-positive artery in the diabetic subject. Not all Aβ-containing arteries had VZV, but all VZV-positive arteries contained Aβ. Conclusions VZV antigen co-localized with Aβ in some affected arteries from two CAA cases, suggesting a possible association between VZV infection and CAA.