Acute renal artery occlusion: Presentation, treatment, and outcome

Abstract

Acute renal artery occlusion is an uncommon disease requiring rapid diagnosis for prevention of kidney loss or permanent kidney damage. The purpose of this study was to identify patients with acute kidney infarction; to characterize their presentation, imaging, and treatment; and to compare the subgroup of patients who underwent catheter-directed thrombolysis (CDT) with those who were treated without intervention. Hospital records between 2005 and 2015 were queried for keywords suggestive of kidney infarction. Patients were divided into two groups: the CDT group and the noninterventional group. Data collected included demographics, comorbidities, methods of diagnosis, and time from presentation to diagnosis. For patients treated with CDT, additional data collected included details of thrombolytic therapy and follow-up studies. The two groups were compared regarding their clinical characteristics and outcome. Forty-two patients were diagnosed with acute kidney infarction; 13 (31%) were treated with CDT and 29 (69%) were treated conservatively. Median time from presentation to diagnosis was 42hours in the CDT group and 32hours in the untreated group. Among the CDT group, complete or partial resolution of the thrombus was seen in all patients. Two required permanent dialysis, both renal transplant patients. Median follow-up was 30months (interquartile range, 2.7-46.2) in the CDT group and 13months (interquartile range, 0.11-16) in the noninterventional group. Mean creatinine clearance at diagnosis and at last follow-up was 74.3 and 54.6mL/min, respectively, in the CDT group (adecrease of 27%; P= .032) and 66.1 and 60mL/min in the conservatively treated group (a decrease of 9%; P= .04). Follow-up imaging was available in nine patients treated with CDT. Mean interval from treatment to follow-up imaging was 13months (range, 1-35months) and consistently showed a functional but smaller treated kidney. (Mean pole-to-pole kidney length at baseline and late follow-up: 10.4cm and 8.5cm, respectively). Most patients presenting with acute kidney infarction are managed conservatively. A subset of patients with complete occlusion of the renal artery undergo CDT with good angiographic results. The treated kidney is expected to decrease in size over time, and overall kidney function is expected to decrease compared with baseline. Deterioration in renal function appears to stabilize and does not continue over time. CDT for acute renal artery occlusion is a safe modalityof therapy and should be attempted for the purpose of kidney salvage, even in the setting of prolonged ischemia.