Porcine Circovirus Type 2-Associated Cerebellar Vasculitis in Postweaning Multisystemic Wasting Syndrome (PMWS)-Affected Pigs

• Published in: Veterinary pathology 2007-09, Vol.44 (5), p.621-634
• Main Authors: Seeliger, F. A., Brügmann, M. L., Kruger, L., Greiser-Wilke, I., Verspohl, J., Segalés, J., Baumgärtner, W.
• Format: Article
• Language: English
• Subjects: Animals; Cerebellum - blood supply; Cerebellum - pathology; Circoviridae Infections - pathology; Circoviridae Infections - veterinary; Circoviridae Infections - virology; Circovirus - genetics; Dermatitis - veterinary; Dermatitis - virology; Genome, Viral; Kidney Diseases - veterinary; Kidney Diseases - virology; Phylogeny; Polymerase Chain Reaction; Porcine Postweaning Multisystemic Wasting Syndrome - pathology; Porcine Postweaning Multisystemic Wasting Syndrome - virology; Swine; Vasculitis - pathology; Vasculitis - veterinary; Vasculitis - virology; Viral Proteins
• ISSN: 0300-9858; 1544-2217
• DOI: 10.1354/vp.44-5-621

Porcine circovirus type 2 (PCV2) is associated with several syndromes in growing pigs, including postweaning multisystemic wasting syndrome and porcine dermatitis and nephropathy syndrome. In the present study, a previously undescribed neurovascular disorder associated with a PCV2 infection is described. Sixteen pigs showed clinical signs of wasting and neurologic deficits. Acute hemorrhages and edema of cerebellar meninges and parenchyma due to a necrotizing vasculitis resulted in degeneration and necrosis of the gray and white matter. Few to numerous PCV2 DNA and antigen-bearing endothelial cells were detected in affected areas of the brain using in situ hybridization and immunohistochemistry. Conventional histochemical stains, as well as the detection of caspase 3 activity and DNA strand breaks by the terminal transferase dUTP nick end labeling assay, showed numerous apoptotic endothelial cells in the vascular lesions observed. Sequencing of various brain-derived PCV2-specific amplicons revealed a strong identity between different isolates and an 89 to 100% identity to previous isolates. The phylogenetic tree showed that there was no clustering of isolates correlating to clinical signs or geographic distribution. This previously undescribed PCV2-associated neurologic disease has features of both postweaning multisystemic wasting syndrome and, to a lesser extent, porcine dermatitis and nephropathy syndrome. The available evidence suggests that direct virus-induced apoptosis of endothelial cells plays a role in the pathogenesis of this unusual PCV2-associated cerebellar vasculitis.