A Case of Polyarteritis Nodosa Associated with Vertebral Artery Vasculitis Treated Successfully with Tocilizumab and Cyclophosphamide.

Pediatric polyarteritis nodosa is rare systemic necrotizing arteritis involving small- and medium-sized muscular arteries characterized by aneurysmal dilatations involving the vessel wall. Aneurysms associated with polyarteritis nodosa are common in visceral arteries; however intracranial aneurysms have also been reported and can be associated with central nervous system symptoms, significant morbidity, and mortality. To our knowledge extracranial involvement of the vertebral arteries has not been reported but has the potential to be deleterious due to fact that they supply the central nervous system vasculature. We present a case of a 3-year-old Haitian boy with polyarteritis nodosa that presented with extracranial vessel involvement of his vertebral arteries. After thorough diagnostic imaging, including a bone scan, ultrasound, Magnetic Resonance Imaging/Angiography, and Computed Tomography Angiography, he was noted to have vertebral artery vasculitis, periostitis, subacute epididymoorchitis, arthritis, and myositis. He met diagnostic criteria for polyarteritis nodosa and was treated with cyclophosphamide, methylprednisolone, and tocilizumab, which resulted in improvement of his inflammatory markers, radiographic findings, and physical symptoms after treatment. To the authors' knowledge, this is the first report of vertebral artery vasculitis in polyarteritis nodosa as well as successful treatment of the condition using the combination cyclophosphamide and tocilizumab for this condition.