Percutaneous transcatheter recanalization in the management of acute renal failure due to sudden occlusion of the renal artery to a solitary kidney

GATA1 regulates the microRNA‑328‑3p/PIM1 axis via circular RNA ITGB1 to promote renal ischemia/reperfusion injury in HK‑2 cells

Acute kidney injury (AKI) is caused by renal ischemia/reperfusion injury (IRI) during kidney transplantation. The levels of both circular RNAs (circRNAs) and microRNAs (miRNAs/miR) appear to be critical for AKI detection. While several RNA interactions in AKI have been found, the regulatory mechanisms between the molecules remain to be fully elucidated. In the present study, miRNA expression profiling analysis was conducted using an online dataset to identify the differentially expressed miRNAs in rats with IRI. miR-328-3p was also found to be downregulated in human kidney-2 (HK-2) cells subjected to hypoxia/reperfusion (H/R), and its overexpression targeting pim-1 proto-oncogene (PIM1) resulted in an increased viability and a reduced apoptosis, as well as in the decreased expression of inflammatory factors upon H/R exposure. Putative targets and circRNAs of miR-328-3p were identified using publically available databases. The inhibition of circRNA integrin beta 1 (ITGB1; circITGB1) suppressed the inflammatory response induced by H/R by sponging miR-328-3p in HK-2 cells. Furthermore, a sequence of the functional ITGB1 promoter was studied for transcription factor GATA binding protein 1 (GATA1) binding sites. GATA1 binds to the ITGB1 promoter, leading to the expression of circITGB1. On the whole, the findings of the present study revealed a regulatory pathway modulating miR-328-3p in IRI, demonstrating that the GATA1-mediated regulation of circITGB1 enhanced the H/R-induced inflammatory response via the miR-328-3p/PIM1 axis.

Reversible acute renal failure as an atypical presentation of ischemic nephropathy

Ischemic nephropathy (IN) is defined as a clinically significant reduction in glomerular filtration rate in patients with hemodynamically significant obstruction to renal artery flow in a solitary functioning kidney or with bilateral renal artery stenosis (RAS). Ischemic nephropathy typically has a subacute to chronic course that may lead to end-stage renal disease. Acute anuric renal failure, which occurs less commonly with IN, is usually associated with moderately severe hypertension and has been attributed to certain risk factors: angiotensin-converting enzyme inhibition, a reduction in blood pressure secondary to antihypertensives or volume contraction, and exposure to contrast media. We present a series of six patients with IN and acute, anuric renal failure without either moderately severe hypertension or the previously defined risk factors. Of these six patients, four had RAS in a solitary kidney and two were found by ultrasound to have disparity in kidney size and bilateral RAS. Within 1 week of surgery, three patients developed renal failure that did not involve the kidney(s) responsible for the anuria and thus mimicked postoperative acute renal failure. Creatinine levels pre-anuria (1.2 to 2.1 mg/dL), during renal failure (5.0 to 12.8 mg/dL), and postrecovery (1.6 to 2.8 mg/dL) showed recovery of renal function, with renal artery bypass in four patients (sustained at 1 year). Two patients refused surgery and are on chronic dialysis. Acute renal failure in IN may occur postoperatively or spontaneously, and emergent intervention (ultrasound, angiography, angioplasty, and/or surgery) in this setting may lead to the correction of RAS and preservation of renal function.

Successful percutaneous balloon catheter treatment of renal artery occlusion and anuria

Progressive renal failure may be due to renal artery stenosis and occlusion. Gradual occlusion of the renal arteries may allow the development of collateral arterial supply sufficient to avoid dialysis. Even when dialysis is required, significant viable renal parenchyma may still be present to allow escape from dialysis following revascularization of one or both kidneys. The chance of success in such cases is thought to be better if the patient still produces a significant amount of urine. We report here a patient who was completely anuric for five days and in whom excellent renal function returned after balloon angioplasty of one of two occluded renal arteries.