A Complex Case of Renal Artery Stenosis in a 3-Year-Old Patient with Neurofibromatosis Type 1 and Secondary Hypertension

We describe a case of a 3-year-old girl with neurofibromatosis type 1 presenting with arterial hypertension, in whom multimodal vascular imaging identified significant right renal artery stenosis. The patient was successfully treated with percutaneous transluminal renal angioplasty; however, post-procedural Doppler ultrasound revealed a transient vascular fistula. Changes in renal arterial inflow during the procedure may have temporarily altered pressure gradients, facilitating the opening of communication involving pre-existing compensatory collateral vessels. This case illustrates the diagnostic value of multimodal vascular imaging in pediatric hypertension and highlights a rare, self-limiting post-interventional vascular phenomenon.