Phaeochromocytoma associated with cardiomyopathy and leukocytoclastic vasculitis in a dog

Phaeochromocytomas are rare tumours of the adrenal medulla that can be associated with various presentations. Many of the better characterized clinical signs, including weakness, tachycardia and tachypnoea, are attributable to excessive and unregulated catecholamine secretion from functional tu-mours. In addition to catecholamine-induced cardiomyopathy and vasospasm, the invasive nature of phaeochromocytomas can lead to occlusion of the caudal vena cava contributing to systemic cardio-vascular compromise. In humans, leukocytoclastic vasculitis is a rarely reported manifestation of cate-cholamine excess associated with phaeochromocytomas. We now describe a dog that had an invasive unilateral phaeochromocytoma with histological evidence of myocardial damage, consistent with catecholamine-induced cardiomyopathy, and leukocytoclastic vasculitis of small vessels in a range of tissues. We conclude that catecholamine excess may have played a role in the pathogenesis of vasculitis in this case. To the best of our knowledge, this is the first documented association between phaeo-chromocytoma and leukocytoclastic vasculitis in a non-human species.& COPY; 2023 The Author(s). Published by Elsevier Ltd. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).

Automated summary

Phaeochromocytomas are rare tumours of the adrenal medulla that can cause various symptoms. Excessive catecholamine secretion from these tumours can lead to weakness, increased heart rate, and rapid breathing. Invasive phaeochromocytomas can also cause occlusion of the caudal vena cava, resulting in systemic cardiovascular compromise. This article reports on a dog with an invasive unilateral phaeochromocytoma that showed myocardial damage consistent with catecholamine-induced cardiomyopathy, as well as leukocytoclastic vasculitis in small vessels in multiple tissues. This is the first documented association between phaeochromocytoma and leukocytoclastic vasculitis in a non-human species.