Multidetector computed tomography findings and correlations with proteinuria in nutcracker syndrome

Abstract

We evaluated the effectiveness of multidetector computed tomography (MDCT) as a diagnostic tool for nutcracker syndrome (NS) and its association with proteinuria. The angle and distance between the aorta and the superior mesenteric artery (SMA), the degree of difference in corticomedullary enhancement (DCE) between kidneys in the nephrographic phase of computed tomography, peak velocity ratio (PVR), and anteroposterior diameter ratio (APDR) in the sonogram were measured. The MDCT results, sonogram results, and the ratio of protein:creatinine were significantly different between NS patients and the controls. The area under the curve for angle, distance, and DCE were 0.895 +/- 0.058, 0.876 +/- 0.063, and 0.942 +/- 0.036, respectively. The cutoff values for angle and distance had sensitivity and specificity values of 96.2 and 80% for <22.4 degrees and 84.6 and 80% for <4.9 mm, respectively. The DCE had a sensitivity of 88.5% and a specificity of 100% for the positive scores. There were significant correlations between the degree of DCE and the ratio of protein:creatinine (r = 0.337, p = 0.031), and between distance and the ratio of protein:creatinine (r = -0.419, p = 0.006). We conclude that MDCT has diagnostic value for NS in children and that MDCT findings are correlated with proteinuria.

Value of micro-proteinuria in combination with ultrasonography of the left renal vein in the diagnosis of orthostatic proteinuria

“…Three potential (20). Recently, some investigators employ CT for the detection of LRV entrapment (21). Ha and Lee reported a girl with 24 h-proteinuria >1.5 g but normal morning urine protein was diagnosed with moderate LRV entrapment on magnetic resonance angiography (MRA); the renal biopsy and pathological examination showed moderate mesangial hyperplasia but normal immunofluorescence and electron microscopic findings; remission was observed after ARB treatment (22).…”

The Teenager With Asymptomatic Proteinuria: Think Orthostatic First

“…The same group recently described the successful use of multidetector computed tomography for the same purpose. 14 Devarajan 6 reported a renal transplant donor known to have OP, in whom during surgery to harvest a kidney, a kink of its vein was detected. After the nephrectomy the donor's proteinuria resolved and the recipient of that kidney never developed proteinuria.…”

Multidetector computed tomography in orthostatic proteinuria?

“…Very recently, Cho et al evaluated children and adolescents with orthostatic proteinuria by means of multidetector computed tomography and noted that both the angle and the distance between the aorta and the superior mesenteric artery were significantly altered in subjects with postural proteinuria [3]. The sophisticated imaging studies of the report further support left renal vein entrapment in the pathogenesis of isolated orthostatic proteinuria.…”

“…Considering the cancer mortality risk attributable to radiation from an abdominal computed tomography, the benign nature of postural proteinuria, and its spontaneous resolution, we strongly advise against the use of multidetector computed tomography in postural proteinuria, as suggested by Cho et al [3]. No imaging studies or renal ultrasound imaging and Doppler flow scanning are currently performed at our institutions in children with isolated postural proteinuria.…”

“…It has been therefore postulated that partial obstruction to the flow in the left renal vein in the upright position alters glomerular microcirculation, thus leading to increased protein filtration [2,3].…”