Comparative outcomes of anticoagulation alone versus anticoagulation plus endovascular intervention in adults with isolated renal vein thrombosis

Abstract

Background: Limited therapeutic strategies are available for adults with isolated renal vein thrombosis (RVT). In the present study, we explore and compare the efficacy of anticoagulation therapy alone vs anticoagulation plus endovascular intervention in the treatment of this rare disease.

Methods: In the present study, we analyzed the clinical data of RVT patients treated in a tertiary referral center in urban China from April 2012 to April 2022. These patients were classified into anticoagulation therapy (best medical treatment [BMT]) and endovascular intervention (endovascular-based treatment [EBT]) groups. The primary end points, including thrombus clearance and renal function changes, were evaluated by measuring the serum creatinine levels and glomerular filtration rates (GFRs).

Results: A total of 40 consecutive patients with RVT (25 men and 15 women) were included in the present study, with a median age of 37 years (range, 18-72 years). Some patients developed symptoms, including 12 with low back pain (30%), 11 with lower extremity edema (28%), and 10 with abdominal pain (30%). Nephrotic syndrome was the underlying etiology for most patients (30 of 40; 75%). Additionally, 28 patients (70%) developed unilateral RVT, including 18 cases of left RVT (45%). Of the 40 patients, 17 had received BMT (42%) and 23 had received EBT (58%). In the acute phase of RVT, defined as <14 days from symptom onset, the EBT group had higher thrombus clearance and better improvement of creatinine and GFR after treatment compared with the BMT group (P < .05). In the subacute phase, defined as 14 to 30 days after symptom onset, thrombus clearance was higher in the EBT group than in the BMT group (P < .05). However, the improvement in creatinine and GFR were insignificantly different between the two groups (P > .05).

Conclusions: The etiologies of RVT can and should be investigated. In the present study, RVT was primarily caused by nephrotic syndrome in young patients and also was attributed to malignancy and lupus nephritis. In addition to anticoagulation therapy, endovascular intervention, including catheter-directed thrombolysis and mechanical thrombectomy, contributed to the improvement of renal function in patients with acute RVT. Endovascular intervention markedly promoted thrombus clearance in patients in the subacute phase but did not improve renal function. Therefore, endovascular intervention should be considered if RVT is diagnosed in the acute phase.

Keywords: Adults; Nephrotic syndrome; Pulmonary embolism; Renal vein thrombosis.

Fig 1

Endovascular treatment of renal vein thrombosis. A, For the "central type" of thrombus located in the main trunk of the renal veins, catheter-directed thrombolysis (CDT) via a renal vein thrombolysis catheter was chosen. B, For the "peripheral type" of thrombus located in the branch of the renal veins, indirect catheter thrombolysis (ICT) via a renal artery catheter was chosen. C, For the "mixed type" of thrombosis involving the main trunk and branches of the renal veins, combined thrombolysis via the renal vein and artery was performed. D, For the "central type" of thrombus located in the main trunk of the renal veins, percutaneous mechanical thrombectomy could also be used.

Fig 2

Contrast-enhanced images of the renal vein on computed tomography venography (CTV) showing thrombosis of the right main renal vein (arrow; coronal plane [A] and transverse plane [C]). Repeat CTV after 1 week of anticoagulation combined with percutaneous mechanical thrombectomy (PMT) showing the right renal vein thrombus had cleared (coronal plane [B] and transverse plane [D]).

Fig 3

Relationship between pulmonary embolism (PE) and locations of renal vein thrombosis (RVT).