Aortic spirocercosis in dogs
Ingested L3S.lupi larvae penetrate the gastric mucosa of the final host, from where they migrate subintimally, in the adventitia and media of the walls of arteries, reaching the cranial aorta within about 3 weeks. Here they may remain as aortic granulomas for 2 - 4 months, before moving to their final destination in the oesophagus, reaching adulthood.
Heavy aortic larval loads can cause severe transmural aortic inflammation with numerous necrotic tracts and proliferative endarteritis. Such aortas are prone to rupture with fatal hemothorax and this frequently occurs in the absence of oesophageal granulomas. The rise in systemic vascular pressure (blood pressure) following tranqulization can put increased shear stresses on an already compromised aorta, making these dogs an anaesthetic risk.