although renal embolization is reported to be a safe and effective therapeutic procedure for embolization of small branches of renal artery , it is mainly used for urological purposes , i.e. vascular malformations , angiomyolipomas , and renal tumors that are not amenable to surgical resection [ 1 , 2 ] .
a search of the literature for the past 20 years reveals that only a few cases of renal amyloidosis [ 3 , 4 , 5 , 6 , 7 ] and severe nephrotic syndrome [ 8 , 9 , 10 , 11 ] have resulted in bilateral renal artery embolization ( rae ) for severe proteinuria .
the limited use of bilateral rae for nephrological purposes may be partly related to its tendency to destroy renal function , which results in anuria and subsequent regular dialysis .
regular dialysis is usually stressful for patients , so some patients may be reluctant to receive bilateral rae for severe proteinuria , which can induce hypoalbuminemia and increase the risk of morbidity and mortality [ 13 , 14 ] .
therefore , doctors and patients with renal amyloidosis and proteinuria face a difficult dilemma in deciding whether to use bilateral rae or supportive treatments .
this study reports a 66-year - old patient with renal amyloidosis and severe proteinuria , who received delayed bilateral rae , until a life - threatening pulmonary edema occurred .
finally , bilateral rae , followed by regular hemodialysis ( hd ) , successfully cured the severe proteinuria and its related symptoms .
a 66-year - old man diagnosed with chronic lymphocytic leukemia had been treated with prednisolone 5 mg per day and cyclophosphamide 25 mg per day since 1995 .
he was referred to our clinic because he had been suffering from renal amyloidosis - related heavy proteinuria ( 21.77 g / day ) , hypoalbuminemia ( 1.4 g / dl ) , and anasarca edema for 6 months . because bilateral rae was not performed , progressive anasarca edema , increased proteinuria ( 31.2 g / day ) , reduced serum albumin ( 0.9 g / dl ) , and dyspnea developed after further conservative treatment with bed rest , salt and water restriction , diuretics such as furosemide 80 mg and hydrochlorothiazide 50 mg trice daily , ramipril 1.25 mg once daily , indomethacin 25 mg trice daily and albumin infusion , for 1 month .
the serum bun ( normal range 820 mg / dl ) and creatinine ( normal range 0.81.5 mg / dl ) levels were increased to 43 and 4.8 mg / dl from 36 and 3.0 mg / dl , respectively . on physical examination ,
body weight was 55 kg , body height 162 cm , blood pressure 7080/5060 mm hg , pulse rate 84 beats per minute , respiratory rate 20 breaths per minute , and body temperature 37c .
laboratory investigation revealed white blood cells ( wbc ) , 4.3  10/l ( normal range 4.511  10/l ) ; hemoglobin , 92
g / l ) , and platelets , 212  10/l ( normal range 150350  10/l ) . unfortunately ,
further breathing difficulty developed in hospital , despite aggressive treatment with intravenous furosemide and albumin infusion .
therefore , the patient underwent bilateral rae ; pure alcohol mixed with lipidol was injected via the orifices of the right and left renal arteries to obliterate the arteries and their branches ( fig .
1 ) . after bilateral rae , no proteinuria was noted , due to anuria . there was only mild nausea , flank pain , and mild fever for 1 day after embolization .
the serum albumin level was increased from 0.9 to 3.5 g / dl within 3 months ( fig .
an increase in muscle mass ( the arm girth increased from 18 to 23 cm , thigh girth from 25 to 35 cm , waistline from 60 to 71 cm , and dry weight from 46 to 57 kg ) was noted during the follow - up period .
hospitalization and protein substitution were no longer needed in the following 2 years ( fig .
, blood pressure was increased from about 7080/5060 to 100120/6070 mm hg in the first year , and 120135/7080 mm hg in the second year after bilateral rae .
although our case had developed severe proteinuria ( > 20 g / day ) , hypoalbuminemia ( 1.4 g / dl ) , and anasarca edema under aggressive diuretic treatment , bed rest , fluid control , angiotensin converting enzymes , and nonsteroid anti - inflammatory drugs and albumin infusion , the patient and family agreed to bilateral rae when the conditions worsened ( urine protein 31.2 g / day and serum albumin 0.9 g / dl ) and a pulmonary edema occurred . after bilateral rae and following regular hd , the patient 's refractory proteinuria , leg edema , and respiratory distress subsided ( fig .
because of the successful outcome in this case and previous reports [ 3 , 4 , 5 , 6 , 7 , 8 , 9 , 10 , 11 ] , it is suggested that treatment with bilateral rae as early as possible may be worthwhile for patients with severe proteinuria resistant to medical therapy . in our case
, concerns about the subsequent regular hd meant that the patient and family refused early bilateral rae .
the patient and family were anxious and wary of further loss of renal function and the stress of regular hd as a result of treatment with rae .
however , prolonged severe proteinuria resistant to medical therapy had caused the patient to reach a life - threatening cachexic state .
in contrast , bilateral rae and subsequent regular hd not only rapidly alleviated proteinuria , anasarca edema , and pulmonary edema , but also resulted in an increase in serum albumin level , with an obvious improvement in nutritional status , muscle mass and body weight , and clinical condition , with an obvious improvement in quality of life .
the patient maintained a steady status for at least the next 2 years . in the meantime , no specific complications have occurred , except for the mild , self - limiting symptoms of post - infarction syndrome , which presented as mild flank pain , fever , and nausea for 1 day after the bilateral rae .
this case and selected previous reports [ 3 , 4 , 5 , 6 , 7 , 8 , 9 , 10 , 11 ] reveal important information for physicians and patients in discussing prognoses and considering the pros and cons of bilateral rae . in conclusion ,
bilateral rae is an alternative , effective , rapid , and safe procedure for the treatment of heavy proteinuria with nephrotic syndrome .
bilateral rae with subsequent hd is useful in breaking a vicious circle and can improve nutritional status and alleviate the life - threatening complications associated with hypoalbuminemia .
 in the case reported here , after prolonged medical therapy resistance , severe proteinuria subsided following bilateral renal artery embolization ( rae ) . thereafter , respiratory distress , anasarca edema , muscle mass , and serum albumin level improved after regular hemodialysis . 
 although rae is reported to be a safe and effective therapeutic procedure , it is rarely used for severe proteinuria with prolonged medical therapy resistance . 
 the limited use of bilateral rae for nephrological purposes may be partly related to its tendency to destroy renal function , which results in anuria and subsequent regular dialysis . however , delayed rae could cause the patient to reach a life - threatening cachexic state and could increase the risk of morbidity and mortality due to severe proteinuria - induced hypoalbuminemia . our case and 
 selected previous reports reveal important information for physicians and patients while discussing prognoses and considering the pros and cons of bilateral rae . 
Introduction
Case Report
Discussion
Disclosure Statement