Pediatric left renal vein entrapment syndrome diagnosed by 99mTc-albumin-conjugate scintigraphy.

BACKGROUND/AIMS: Procedures for diagnosis of left renal vein entrapment syndrome (LRVES) in children have been either invasive or limited in accuracy. We examined scintigraphy with (99m)Tc-diethylene triamine pentaacetic acid-conjugated human serum albumin ((99m)Tc-HSA-D) scintigraphy in childhood LRVES, demonstrating selective left renal nuclides excretion. We also measured peak velocity using pulse Doppler ultrasonography, calculating pressure differences between inferior vena cava and left renal vein using a simplified Bernoulli equation.

METHODS

Thirteen patients provisionally diagnosed with LRVES by ultrasonography combined with other imaging such as magnetic resonance angiography and three-dimensional computer tomography (CT) were examined.

RESULTS

Four children showing repeated gross hematuria all showed pressure differences exceeding 3.0 mm Hg. Selective left renal albumin excretion was demonstrated by (99m)Tc-HSA-D scintigraphy. Single-photon emission CT also showed accumulation in a site consistent with the left renal pelvis. Among 9 children manifesting mainly orthostatic proteinuria, selective left renal albumin excretion examined by (99m)Tc-HSA-D scintigraphy was demonstrated only in those with proteinuria exceeding 1 g/g Cr after standing in a lordotic position. Pressure differences in patients with orthostatic proteinuria were unrelated to proteinuria severity.

CONCLUSIONS

Combining pulse Doppler ultrasonography with (99m)Tc-HSA-D scintigraphy, both noninvasive and safe in children, may suffice for diagnosis of LRVES, especially with gross hematuria.