Imaging in renal artery stenosis associated with Takayasu arteritis

A 20-year-old female with Takayasu arteritis and secondary hyperaldosteronism diagnosis presented a 2-hour history of oppressive 10/10 intensity frontal headache and abdominal pain in the left iliac fossa. On further enquiry, she reported a history of elevated blood pressure, presenting 200/180 on admission, being managed with nitroglycerin and prazosin, subsequently decreasing to 170/120. Physical examination was unremarkable. On routine blood examination, elevated erythrocyte sedimentation rate (28 mm/hr) was the only significant finding. Chest radiograph showed unremarkable findings.

Abdominal CT angiography and 3D model (Figure 1) revealed concentric thickening of the abdominal aorta from the origin of the superior mesenteric artery, both renal arteries, right common iliac artery, and the ipsilateral internal iliac artery. There was a decrease in the vascular lumen indicative of Takayasu arteritis. FDG PET CT (Figure 2) was done for further evaluation and characterisation of arteritis activity, corroborating no additional findings.

Intrarenal vessels, as well as renal arteries, were assessed using comparative renal ultrasound (Figure 3). Left kidney colour and spectral Doppler revealed a “tardus parvus” pattern with a peak systolic velocity of up to 119 cm/s, indicating proximal stenosis at intrarenal and renal arteries. The aorto-renal relationship appeared normal.

Percutaneous transluminal balloon angioplasty of the left renal artery was performed using a 2.5 x 20 mm balloon to dilate the ostial lesion. Control angiography is subsequently performed, observing adequate flow and vessel expansion (Figure 4).

Takayasu arteritis is a chronic inflammatory condition of unknown aetiology; in this case report, it involved important elements such as left renal artery with findings and complications such as a decrease in the vascular lumen demonstrated by Doppler US and successfully treated surgically by percutaneous transluminal balloon angioplasty. Takayasu arteritis is a common disease in Japan, India, Southeast Asia and Mexico, so it is important to report the diagnostic and therapeutic conduct [1]. It is presented for educational purposes.

The spectrum of findings in CT angiography includes concentric arterial wall thickening, mainly affecting the aorta and its branches and the pulmonary arteries, which can cause stenoses or occlusions, as in this case [2]. Previous studies have shown that renal artery stenosis is a common complication in patients with TA. Li Cavoli et al. [3] found that visceral arterial involvement is reported in 11% to 68% of Takayasu arteritis patients, typically in the form of steno-occlusive lesions.

Doppler ultrasound revealed a “tardus parvus” spectral pattern in the left renal artery, indicative of proximal stenosis [4]. This finding underscores the importance of monitoring renal function in TA patients, as renal artery stenosis can lead to renovascular hypertension and renal failure [5]. Indications for revascularisation procedures include hypertension in the context of renal artery stenosis [6].

Renal hypertension, as the hypertension and significant stenosis of the renal artery, is the main potentially curable cause of high blood pressure. Atherosclerosis and fibromuscular dysplasia are the predominant aetiologies and differential diagnoses for Takayasu arteritis, based on the frequency of occurrence [7]. CT angiography revealed diffuse thickening of the aortic walls, with the absence of calcification; this suggested that the thickening was caused by an inflammatory condition, such as arteritis, rather than atherosclerosis. In case of considering atherosclerosis as a differential diagnosis, FDG PET-CT could reveal diffuse hypermetabolism of the walls of the aorta and large vessels consistent with Takayasu arteritis [8]. Can be difficult to differentiate Takayasu arteritis from fibromuscular dysplasia, however, acute-phase reactants are elevated in arteritis, not in fibromuscular dysplasia. It is important because arteritis and fibromuscular dysplasia can both have a severe clinical course, but require distinct management [9,10].

This report includes useful imaging methods for diagnosing, treating, and monitoring patients with renal artery stenosis associated with Takayasu arteritis. Left renal percutaneous transluminal angioplasty was performed without complications, achieving renal revascularisation and normalisation of blood pressure, significantly improving the patient’s prognosis.

All patient data has been completely anonymised throughout the entire manuscript and related files.