Aortic and iliac thrombosis in a dog with adrenal-dependent hypercortisolism due to bilateral adrenocortical adenoma

ABSTRACT: Hypercortisolism is a common endocrinopathy in dogs; however, in a few cases, bilateral functional adrenocortical adenomas cause spontaneous disease, and thrombotic events are considered uncommon complications. The aim of this report was to describe a case of bilateral adrenocortical adenoma in a dog with hyperadrenocorticism associated with distal aortic and iliac thrombosis, with emphasis on clinical and pathological aspects. A 15-year-old spayed female Dachshund with a previous clinical history of hyperadrenocorticism presented with acute bilateral hindlimb paraparesis. A vertebral thoracolumbar radiography was performed and did not present any evidence of intervertebral disk disease or vertebral abnormalities; however, abdominal ultrasound and vascular Doppler evaluation revealed bilateral adrenal enlargement in addition to an aortic and external iliac artery thrombus. The animal was euthanized. At necropsy, both adrenal glands were enlarged by well-demarcated neoplastic nodules in the parenchyma, and a thrombus caudal to the abdominal aorta bifurcation within the external iliac arteries that extended to the left external iliac artery was noted. Histological evaluation revealed a well-differentiated neoplastic proliferation of cortical epithelial cells, consistent with bilateral adenoma, and muscular necrosis in the pelvic limbs was also observed. Bilateral functional adrenocortical adenoma; although, very rare, should be considered as a cause of hypercortisolism, and aortic thrombosis in dogs should be considered as a possible consequence.

摘要：皮质醇增多症（Hypercortisolism）是犬类常见的内分泌疾病，少数情况下，双侧功能性肾上腺皮质腺瘤（adrenocortical adenoma）可引发自发性皮质醇增多症，而血栓事件（thrombotic events）被视为该病的罕见并发症。本报告旨在描述一例犬双侧肾上腺皮质腺瘤继发皮质醇增多症，并伴发远端主动脉及髂动脉血栓的病例，重点阐述其临床与病理特征。受试动物为一只15岁已绝育的雌性腊肠犬，既往有皮质醇增多症病史，因急性双侧后肢轻瘫就诊。对其进行胸腰椎X线摄影（vertebral thoracolumbar radiography）检查，未发现椎间盘疾病或脊柱异常征象；但腹部超声（abdominal ultrasound）及血管多普勒（vascular Doppler）评估显示双侧肾上腺增大，同时检出主动脉及髂外动脉血栓。该动物最终实施安乐死。尸检（necropsy）结果显示：双侧肾上腺实质内可见边界清晰的肿瘤性结节，导致腺体体积增大；于腹主动脉分叉后方的髂外动脉内发现血栓形成，且该血栓延伸至左侧髂外动脉。组织病理学检查（histological evaluation）可见皮质上皮细胞呈分化良好的肿瘤性增殖，符合双侧肾上腺皮质腺瘤的病理特征，同时观察到后肢肌肉坏死。尽管双侧功能性肾上腺皮质腺瘤极为罕见，但仍应将其列为犬类皮质醇增多症的潜在病因之一；而犬主动脉血栓也应被视为该病可能的并发症。