Renal Stem Cells, Renal Resistive Index, and Neutrophil Gelatinase Associated Lipocalin Changes After Revascularization in Patients With Renovascular Hypertension and Ischemic Nephropathy

Background: Percutaneous transluminal renal angioplasty (PTRA) with or without stenting is the gold standard therapy in patients with atherosclerotic renal artery stenosis (aRAS). However, therapeutic success depends on the correct timing of revascularization and the reversibility of the renal damage. Materials and methods: We report a case series of patients treated with PTRA for renovascular hypertension and ischemic nephropathy. We measured bilateral renal resistive index (RRI), circulating renal stem cells (RSC), and Neutrophil Gelatinase Associated Lipocalin (NGAL) at baseline and after PTRA at different time points to understand their changes in post-revascularization. Results: At baseline, the studied patients (n=5) had different RSC levels. After PTRAs, all patients showed an improvement in blood pressure, while renal function varied differently within the studied subjects. RRI >0.75 at baseline and the absence of NGAL decrease after PTRAs were associated with post-PTRA renal function worsening, despite an increase of RSC in all patients. Conclusions: Although limited to a few patients, our observation allowed the exploration of the behaviour of the studied parameters in different degrees of renal ischemia. This revealed different disease models suggesting the importance of further investigations in larger and homogeneous cohorts to confirm that a greater basal RSC percentage, low RRI values before PTRA, and a post-revascularization NGAL reduction could be related to better renal outcomes in aRAS patients.