the incidence of renal infarction in an autopsy study was 1.4% , whereas clinical diagnosis was made in only 0.014% of the studied patients .
the clinical manifestations of renal artery thrombosis vary , depending on whether the occlusion affects both renal arteries or not . delay of the correct diagnosis may prove disastrous for the patient .
our case is probably the first one in english literature describing a patient with unilateral renal artery thrombosis after lobectomy for lung cancer .
a 53-year - old female patient was admitted to our hospital with the diagnosis of lung cancer .
her medical history was clear , except that she was a social drinker and smoker ( 3 - 4 glasses of wine / week , 5 cigarettes / day for 25 years ) . physical examination and blood test analysis were normal , and cardiac function was found to be excellent .
the preoperative transbronchial needle aspiration cytology revealed an adenocarcinoma in the left upper lobe . computed tomography ( ct ) of the thorax , abdomen and brain revealed nothing apart from a mass located in the left upper lobe , 2 cm in diameter .
the patient received a formal left upper lobectomy in combination with mediastinal lymph node sampling .
no complications were observed during the operation , and the immediate postoperative period was straightforward until the third postoperative day , when she began to complain of a flank pain located at the lower side of the left hemithorax and the nearby lumbar area .
the pain was not affected by respiratory movements and position changes , and it was continuous without radiation .
laboratory data showed a minor elevation of white blood cell count ( 12,500 cells / mm ) and lactate dehydrogenase ( 371
consequently , the patient was treated with painkillers and anti - inflammatory agents . despite the medication given , pain persisted for the next 24 h without any changes .
an upper abdomen ultrasound scan was performed combined with a chest x - ray revealing nothing that could explain the condition .
an expert nephrologist was called in order to manage the problem . however , precious time was already lost and further therapy with thrombolytics did not offer significant improvement , since the left kidney was considered already nonfunctioning .
the levels of blood urea nitrogen and creatinine did not show remarkable elevation compared with the preoperative ones ( urea : 33  41 mg / dl , creatinine : 0.71  0.83 mg / dl ) .
the patient was discharged two weeks after the operation and anticoagulation therapy with warfarin was given .
six months later , renal function remains satisfying and the patient is free of any symptoms .
it is of crucial importance for acute renal artery thrombosis , although it is an uncommon situation , to be diagnosed early . in the vast majority of the cases , however , significant delay is the rule , causing irreversible damage to the kidney .
the clinical presentations of renal arterial thrombosis are not specific for the disease and usually include flank pain originating from the ipsilateral lumbar area , accompanied by fever , nausea and vomiting
anuria or oliguria combined with proteinuria or hematuria are findings indicating bilateral renal artery occlusion .
blood tests are not apt to establish an accurate diagnosis because of lack in sensitivity and specificity .
common causes of renal artery occlusion include congestive heart failure , atrial fibrillation , and valvular or ischemic heart disease . moreover , trauma , clotting disorders , cancer and some rare hereditary diseases are also mentioned .
plain x - ray and ultrasonography can be significantly helpful , but the final diagnosis is usually determined by contrast - enhanced ct .
invasive diagnostic tools such as renal artery angiography are not without complications . in our case
, the diagnosis was delayed and as a result the left kidney lost its function . given that the patient was free of cardiac diseases and clotting disorders , lung cancer could have been the cause for renal arterial thrombosis .
although the patient was receiving subcutaneous low molecular weight heparin 3,500 iu from the first postoperative day , this very serious complication did happen .
diagnosis was reached incidentally with the help of contrast - enhanced ct , which seems to be the gold standard for renal artery occlusion diagnosis .
therapy in acute renal thrombosis typically consists of low molecular weight heparin in the acute phase , followed by warfarin .
the value of antiplatelets is still under study . because of the high risk for more thromboembolic complications in these patients it is advisable that the anticoagulation treatment should be continued , and a careful follow - up is mandatory
in conclusion , renal arterial thrombosis is a rare and serious condition , which should be diagnosed early .
nonspecific symptomatology complicates the differential diagnosis and a high level of suspicion is required in order to not lose precious time .
if lumbar flank pain appears and all other possible diagnoses are excluded , contrast - enhanced ct should be considered .
apart from the usual causes , the clinician should keep in mind this extremely uncommon case , which may be the first one described in english literature .
 acute renal arterial thrombosis is a rare but very urgent situation demanding immediate treatment . 
 it is characterized by unspecific symptomatology which often misleads the clinicians . as a result 
 , precious time can be lost until the correct diagnosis is reached . 
 the case of a 53-year - old female who underwent a left upper lobectomy for lung cancer is presented . on the third postoperative day , 
 the patient began to complain of a flank pain located at the lower side of the left hemithorax and the nearby lumbar area . 
 a renal arterial thrombosis was finally diagnosed and subcutaneous low molecular weight heparin was started immediately . 
 the patient was discharged two weeks later and anticoagulation therapy with warfarin was given . 
 six months later , renal function remains satisfying and the patient is free of any symptoms . 
 this is probably the first case in english literature of renal arterial thrombosis following lobectomy for lung cancer . 
Introduction
Case Report
Discussion
Conclusions