Case

A 7-year-old boy, born to nonconsanguineous parents, was admitted to the pediatric department for evaluation of severe arterial hypertension. He had a history of postvaricella myelitis, which manifested as acute paraplegia and ultimately resolved. He also had difficulties with learning and communicating. He had been experiencing headaches and dizziness for the past month. At admission, his blood pressure was very high, at 180/120 mmHg in both limbs. The physical examination revealed a distinctive facial phenotype characterized by periorbital fullness, short palpebral fissures, midface hypoplasia, a wide mouth with a thick and everted lower lip, and dental spacing irregularities (Fig. 1). The cardiovascular examination showed normal heart sounds, with no murmurs, cervical or abdominal vascular bruits, or signs of heart failure. The neurological examination was normal. The fundus examination showed signs of early hypertensive retinopathy. The first lab tests showed a hemoglobin level of 12.5 g/dL, a white blood cell count of 7790/mm³ (neutrophils 6154/mm³), and a platelet count of 266,000/mm³. The serum urea was 0.19 g/L, and the creatinine was 5.1 mg/L. The serum electrolytes (Na⁺ 139 mmol/L, K⁺ 4.1 mmol/L) and total calcium (94 mg/L) were all normal. The level of thyroid-stimulating hormone was normal. Williams–Beuren syndrome (WBS) was diagnosed based on characteristic dysmorphic features, psychomotor delay, and fluorescence in situ hybridization showing hemizygosity at the elastin (ELN) locus on chromosome 7q11.23. Transthoracic echocardiography showed concentric left ventricular hypertrophy with a normal ejection fraction and no signs of congenital heart disease. Renal Doppler ultrasound revealed bilateral stenosis of the proximal renal arteries, with slightly reduced downstream systolic velocities (Fig. 2). Thoraco-abdominal CT angiography revealed significant stenosis in the ostial and postostial segments of both renal arteries, with preserved renal morphology and no abnormalities in the visceral branches of the aorta (Fig. 3). The patient subsequently underwent bilateral renal angioplasty. Angiography confirmed that the renal artery ostium on the right side was severely narrowed, extending 1 cm into the trunk. The left renal artery, on the other hand, showed moderate narrowing. Angioplasty was performed, leaving a stenosis of about 30%. The postoperative outcome was favorable. Follow-up demonstrated a marked reduction in blood pressure, which was successfully controlled with a combination of calcium-channel blockers and beta-blockers. left polar renal artery Al stenosis of the proximal and ostial renal arteries, resulting in the absence of measurable Doppler flow in these segments.•Patency of the hilar, segmental, and interlobar renal arteries bilaterally.•Doppler flow analysis demonstrates preserved peak systolic velocities (PSV) within the renal arteries, with preserved resistive indices of approximately:0.53 on the right.0.58 on the left.•At the level of the intrarenal arteries, there is a slight decrease in systolic velocities (around 50 cm/s), with low resistive indices.

Fig. 1: The patient exhibits the distinctive craniofacial phenotype of Williams–Beuren syndrome, characterized by periorbital fullness, short palpebral fissures, midface hypoplasia, a wide mouth with a thick, everted lower lip, and dental spacing irregularities.

Fig. 2: Color and spectral Doppler ultrasound examination demonstrated no measurable Doppler flow in the ostial and proximal segments of both renal arteries, consistent with severe bilateral proximal renal artery stenosis. Distal perfusion was preserved, with patent hilar, segmental, and interlobar renal arteries bilaterally. Intrarenal Doppler analysis revealed mildly reduced peak systolic velocities (approximately 50 cm/s) with preserved low resistive indices (RI: 0.53 on the right and 0.58 on the left). No prolongation of systolic acceleration time was observed, and no significant asymmetry between the 2 kidneys was detected.

Fig. 3: CT angiography confirmed severe, symmetrical bilateral renal artery stenosis involving the ostial and proximal segments, with an estimated luminal narrowing greater than 90%. (A–D) Coronal maximum-intensity projection (MIP) reconstructions obtained following contrast-enhanced CT angiography. Yellow arrows indicate severe bilateral ostial and postostial renal artery stenoses. Distal renal arterial segments remain patent with preserved opacification of the segmental and interlobar branches. (E) Three-dimensional volume-rendered (VRT) reconstruction demonstrating bilateral narrowing at the origins of the renal arteries arising from an otherwise normal abdominal aorta. (F) Axial contrast-enhanced CT angiographic image showing marked narrowing of both renal artery ostia (yellow arrows). These findings correlate with the Doppler ultrasound examination, which demonstrated absent measurable flow at the ostial and proximal renal artery segments, supporting the diagnosis of severe bilateral proximal renal artery stenosis.