The pain can be intense and diffuse, or can be more localized in areas like the shoulder, neck, hip or along the back. There can be associated neurologic deficits. Nonregenerative anemia, hypoalbuminemia, and a mature neutrophilia are common. Histology shows periarteritis in the heart and meninges, and subdural and extradural spinal cord hemorrhage. This may be an autoimmune disease.
Some cases undergo spontaneous regression.
There is often a neutrophilic pleocytosis of the CSF, combined with an inability to identify an infectious agent in the spinal fluid. Pathologic features of naturally occurring juvenile polyarteritis in beagle dogs. Systemic necrotizing vasculitis in nine young beagles. Necrotizing vasculitis of the extradural and intradural spinal meningeal arteries has been reported to occur in young dogs of several breeds. Pathologic changes that have been describe include fibrinoid generation, intimal and medial necrosis, inflammatory cell infiltration, periadventitial accumulation of inflammatory cells, meningeal fibrosis, and hyalinization and mineralization of meningeal arterial walls.