Temporal artery examination may be needed to distinguish VZV from GCA

Previous cases have demonstrated that giant cell arteritis (GCA) and multifocal varicella-zoster virus (VZV) vasculopathy with temporal artery infection have overlapping clinical features and laboratory abnormalities. The authors searched for the presence of VZV antigen in archived biopsy-negative temporal arteries from 24 subjects with clinically suspected GCA.

VZV antigen, but not HSV-1 antigen, was found in five subjects, all of whom presented with clinical and laboratory features of GCA and early visual disturbances.

The authors note several important findings from this study. First, VZV vasculopathy can present with the full spectrum of anterior visual pathway injuries observed in GCA. In these five cases they observed posterior ischemic optic neuropathy, transient ischemia, anterior ischemic optic neuropathy, and central retinal artery occlusion 

Second, multifocal VZV vasculopathy may exhibit many of the same clinical features (headache, polymyalgia rheumatica, TA tenderness) and laboratory abnormalities seen in GCA. This overlap of clinical and laboratory abnormalities in the disorders underscores the need for rapid, accurate diagnosis because patients with multifocal VZV vasculopathy require antiviral treatment.

Third, the association of multifocal VZV vasculopathy with AION indicates that virus reactivation may be associated with some cases of nonarteritic AION, a common cause of optic neuropathy in patients older than 50 years.

The authors conclude that patients presenting with clinical symptoms, signs and laboratory abnormalities consistent with GCA may require temporal artery examination to investigate the possibility of multifocal VZV vasculopathy.