Background Previous randomized controlled trials of revascularization for atherosclerotic renal artery stenosis (ARAS) were not successful. We investigated the effects of percutaneous transluminal angioplasty with stent insertion (PTA/S) on kidney function and blood pressure (BP) control in patients with ARAS. Methods From 2000 to 2017, 47 subjects who underwent PTA/S for ARAS were identified. A high-risk group was defined, composed of patients having one or more of the following clinical presentations: pulmonary edema, refractory hypertension, and rapid deterioration of kidney function. Subjects who met the criteria of ‘kidney function improvement’ or ‘hypertension improvement’ after PTA/S were classified as responders. Results Twenty-one (44.7%) subjects were classified into the high-risk group. Two subjects (8.0%) in the low-risk group (n = 25) and 5 subjects (27.8%) in the high-risk group (n = 18) showed improvement in kidney function after PTA/S ( P = 0.110). In patients with rapid decline of kidney function, estimated glomerular filtration rate improved from 28 (interquartile range [IQR], 10–45) mL/min/1.73 m 2 to 41 (IQR, 16–67) mL/min/1.73 m 2 at 4 months after PTA/S, although the difference was not significant ( P = 0.084). Regarding BP control, 9 (36.0%) and 14 (77.8%) subjects showed improvement after PTA/S in the low- (n = 25) and high-risk (n = 18) groups, respectively ( P = 0.007). In patients with refractory hypertension, the systolic BP dropped from 157 (IQR, 150–164) mmHg to 140 (IQR, 131–148) mmHg at 4 months after PTA/S ( P = 0.005). Twenty-five subjects were defined as responders and comprised a significant proportion of the high-risk group ( P = 0.004). Conclusion PTA/S might improve BP control and kidney function in patients with ARAS presenting with high-risk clinical features. The optimal application of PTA/S should be based on individual assessment of the clinical significance of renal artery stenosis.

Crystalline nephropathy is a rare yet well-known condition associated with multiple myeloma and other light chain–secreting disorders. Paraproteins that are resistant to proteolysis crystallize within proximal tubular cells and cause light-chain proximal tubulopathy, which presents clinically as Fanconi syndrome. Podocytes are rarely affected, and the crystalline inclusions within podocytes are typically precipitated, yielding significant glomerular proteinuria. Here we report a case of extensive crystalline inclusions primarily within podocytes and proximal tubules that presented only with Fanconi syndrome and renal insufficiency. Despite the presence of extensive crystalline inclusions in podocytes and diffuse foot process effacement, the patient had no clinical evidence suggestive of podocyte injury.