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takayasu 's arteritis ( ta ) frequently affects the ascending aorta and aortic arch , causing obstruction of the aorta and its major arteries .
the pathology is a panarteritis , characterized by mononuclear cells and occasionally giant cells infiltration , with marked intimal hyperplasia , medial and adventitial thickening , and , in the chronic form , fibrotic occlusion.1 ) medical therapy with corticosteroids and immunosuppressants is generally recommended in active inflammatory phase of ta.1 ) renal artery stenosis ( ras ) is observed in the 38 - 40% of angiographically confirmed ta patients.2)3 ) the disease progress of ras is directly associated with the aggravation of hypertension and renal function deterioration , therefore ras constitutes a main prognostic factor of ta.4 ) percutaneous angioplasty ( pta ) and stenting in the context of acute oliguric renal failure due to severe ras in a solitary functioning kidney when the function of the contralateral kidney had been completely lost due to renal artery ( ra ) occlusion in ta is rarely reported in the literature.5 ) we present a patient who developed acute oliguric renal failure due to severe ras in a solitary functioning kidney successfully treated with pta and stenting .
a 31-year - old female was referred to our institution with a two - day history of acute onset generalized edema and oliguria .
her vital signs were as follows : blood pressure ( bp ) : 170/110 mmhg , pulse rate : 76/minute , respiratory rate : 23/minute , body temperature : 36.7 . on examination , she appeared swollen and pre - tibial pitting edema was evident .
mild crackles were appreciated in the lower lung fields . the patient had been admitted to our institution 9 years ago for investigation of bp inequality ( 240/160 mmhg in left arm , 140/70 mmhg in right arm ) . at that time ,
an abdominal aortic bruit was audible and erythrocyte sedimentation rate ( esr ) was elevated up to 76 mm / h with blood urea nitrogen ( bun ) , creatinine ( cr ) within the normal range . given the high suspicion for ras , we performed a technetium - diethylene triamine pentaacetic acid ( tc - dtpa ) renal scan , which demonstrated severely reduced left kidney function .
the patient 's left ra was almost completely occluded and the right ra was normal on angiography .
the patient was recommended to undergo left ra bypass surgery and corticosteroid therapy , but she declined surgery and was discharged with oral corticosteroids and antihypertensives .
the patient was investigated again four years ago with a three - day history of generalized edema and reduced urine output , followed by vomiting and diarrhea secondary to gastroenteritis for one week .
her cr at that time was elevated up to 14.7 mg / dl but subsequently returned to 1.8 mg / dl following hemodialysis .
, she remained well on medical therapy at a local clinic , and her cr recorded at a local laboratory was 1.9 mg / dl two weeks prior to the latest admission . her blood chemistry when she presented to emergency triage in this time were as follows : sodium 128
meq / l , potassium 5.3 meq / l , bun 84 mg / dl , cr 11.8 mg / dl , c - reactive protein 0.7 mg / dl , and esr 72 mm / h .
she subsequently underwent emergent hemodialysis twice , and her cr returned to 1.9 mg / dl with recovered urine output . computed tomography ( ct )
scan of the abdomen and pelvis revealed severely contracted and non - functioning left kidney due to chronic complete occlusion of the left ra while a new , severe , right ras was noted ( fig .
angiogram confirmed complete left ra occlusion and demonstrated 95% stenosis in the proximal portion of the right ra ( fig .
this patient 's stenotic left ra and normal right ra demonstrated 9 years ago had markedly progressed to complete left ra occlusion and severe right ras , resulting in acute oliguric renal failure .
decision was made to perform pta and stenting for the newly diagnosed right ras , which perfused her solitary functioning kidney .
she was managed with aspirin and clopidogrel for three days prior to the procedure . overnight intraveous saline hydration ( 1.5 cc / kg / h for 12 hours ) and preprocedural intravenous acetlycysteine was prescribed.6 ) her cr was 2.1 mg / dl on the day of procedure .
vista brite rdc guiding catheter ( cordis , warren , nj , usa ) was adjusted to around the right ra ostium to prevent the catheter tip induced renal ostial or aortic wall damage .
the " no - touch technique " was applied during the procedure using a 0.035-inch j curved - terumo wire ( terumo , tokyo , japan ) which separated the guiding catheter tip from ra ostium and a 0.014-inch runthrough wire ( terumo , tokyo , japan ) was used to drive interventional devices ( fig .
1c).7 ) the lesion was pre - dilated with a savvy 3.520 mm balloon ( cordis , warren , nj , usa ) at 12 atm ( 3.81 mm ) .
a genesis 724 mm balloon expandable stent ( cordis , warren , nj , usa ) was implanted with nominal pressure and ostial stent flaring was performed at 16 atm ( 7.30 mm ) for 15 seconds .
the procedure was completed after amiia 6.020 mm balloon ( cordis , warren , nj , usa ) inflation at 12 atm ( 5.12 mm ) .
1d ) a total of 120 cc of visipaque ( ge healthcare , princeton , nj , usa ) was used .
postprocedural hemodialysis was performed for 2 hours.8 ) patient was discharged after 2 days with dose - reduced antihypertensives and prednisolone .
the patient currently remains well with a cr in the normal range 11 months following hospitalization .
pta is generally accepted as a less invasive , efficacious and safe treatment modality compared to surgical bypass , which is associated with higher morbidity.9 ) there are some published data demonstrating satisfactory results with pta in treatment of ta induced ras .
sharma et al.10 ) reported that pta with or without stenting is a safe and efficacious modality to relief stenotic lesion in 20 patients with ta in a study with at least 6 months ' follow - up .
tanaka et al.11 ) examined the efficacy of conventional balloon angioplasty and cutting balloon angioplasty for the treatment of non - arteriosclerotic ras in 20 patients .
we chose pta as a first line treatment option for several reasons in our patient .
first , she adamantly refused bypass surgery . secondly , pta was not inferior to surgical bypass as a treatment modality to control hypertension and preserve renal function in ras.9 ) to minimize contrast induced nephropathy , we administrated sufficient amounts of saline and acetylcysteine before the procedure and used the iso - osmolar contrast agents followed by hemodialysis after intervention based on previous recommendations in the medical literature.6)8)12 ) the usefulness of distal protection device or carbon dioxide angiography in renovascular intervention has been controversial and we chose not employ them for our patient.13)14 ) long term complications of pta / stenting include restenosis , thrombotic occlusion , stent fracture and migration .
if bp elevation or renal function deterioration occurs during follow - up , arterial patency should be examined with duplex ultrasound , magnetic resonance , ct or selective angiography .
this patient had originally been managed with four types of antihypertensive medications : nifedipine 66 mg bid , atenolol 50 mg qd , losartan 50 mg qd , and furosemide 40 mg qd at the time of admission , but only nifedipine 66 mg bid was required after pta / stenting . at her
follow up 11 months post - procedure , her cr level was maintained within the normal range .
our patient is doing well following ra pta and stenting against the background of acute oliguric renal failure due to ta induced critical ras in a solitary functioning kidney .
however , the optimal use of ra revascularization is poorly defined and the exact indications and clinical applications of ra revascularization in ras are evolving.15 ) when making clinical decisions on renal revascularization one must assess the severity and functional significance of ras ( renal ischemia ) , the condition of the kidneys ( nephropathy ) and the association between ras and vital organ injury.15 ) the risks and benefits of ra pta will be improved by careful patient selection.15 ) better results will be achieved in patients with vital organ injury , renal ischemia in the absence of nephropathy . given the limited clinical trial outcomes and observational case reports , pta and stenting
should be considered a safe and efficacious treatment modality for ta induced acute renal failure due to ras in a solitary functioning kidney .
takayasu 's arteritis ( ta ) is a nonspecific , chronic and stenotic panarteritis which usually involves the aorta and its major branches . 
 corticosteroid and immunosuppressants are recommended to manage the acute inflammatory phase , but their long term benefits are uncertain . blood pressure ( bp ) control during the chronic phase of ta is essential to preserve renal function , which is associated with the patient 's long - term prognosis and survival . 
 revascularization in organ damaging arterial stenosis with percutaneous angioplasty ( pta)/stenting or bypass surgery have been accepted as established treatment options in chronic complicated phase of ta . 
 we present a case of a 31-year - old female patient with a two - day history of sudden onset oliguria and generalized edema whose acute oliguric renal failure was successfully reversed following pta and stenting in a solitary functioning kidney with critical renal artery stenosis ( ras ) caused by ta .