Renal Artery Involvement in Pediatric-Onset Takayasu Arteritis: Renal Characteristics and Mid-Term Follow-up Outcomes

Renal artery involvement (RAI) can cause renovascular hypertension and/or organ dysfunction in Takayasu arteritis (TA). The literature includes few data regarding renal involvement in pediatric-onset TA patients. We aimed to describe the renal characteristics, management, and outcomes in TA patients with RAI.We retrospectively reviewed the clinical, laboratory, and radiological findings, treatments, and outcomes in TA patients with RAI, diagnosed between 2008 and 2022.Nine of 20 pediatric-onset TA patients had RAI; their median age was 14.7 (13.1-15.5) years. Five patients had bilateral RAI. Six patients presented with hypertension, 2 of which as hypertensive emergency. Five patients had proteinuria (median urine protein/ creatinine ratio: 1.75 mg/mg), one patient had microscopic hematuria. Kidney size asymmetry was detected in 5 patients. The median duration of follow-up was 35 months (22-45). All patients received steroids, and TNF-α and/or IL-6 inhibitors. One patient underwent percutaneous transluminal angioplasty (PTA), 2 patients underwent thoraco-abdominal aortic and aortorenal bypass. At last visit there was no progression in renovascular findings in 75% of the patients, and all patients had an eGFR>60 ml/min/1.73m².Hypertension, proteinuria, and kidney size asymmetry can accompany a substantial number of pediatric-onset TA patients with RAI. Prompt initiation of treatment, including PTA or surgery, result in good mid-term renal outcomes.