Doppler ultrasonographic indices in diagnosing nutcracker syndrome in children.
To elucidate the Doppler ultrasonographic cut-off value of nutcracker syndrome causing hematuria in children, we analyzed Doppler spectral findings between 15 children with nutcracker syndrome and 15 age- and sex-matched normal control subjects. A follow-up Doppler ultrasound (US) was also performed in children with nutcracker syndrome when hematuria subsided completely after a median period of 1.7 years (range: 1.0-3.5 years) (relieved nutcracker syndrome). The peak velocity (PV) ratios of the left renal vein (LRV) were significantly higher in children with nutcracker syndrome than in those with relieved nutcracker syndrome (P<0.0001) and normal children (P<0.0001). The PV ratios of the LRV at the follow-up US were significantly higher than those in the control subjects (P=0.019). None of the 15 normal children showed PV ratios of the LRV>3.7, but five of the 15 children with relieved nutcracker syndrome without hematuria had PV ratios of 3.91-5.02. When we set the cut-off values for nutcracker syndrome at the mean+/-2 SD (mean: 2.95+/-0.92, range: 1.60-5.02) of 30 controls (normal children and relieved nutcracker without hematuria), the calculated cut-off value was 4.8, and the sensitivity and specificity were 100% and 93%, respectively. Given its high sensitivity, renal Doppler US can be used as a useful initial non-invasive test in the diagnosis of nutcracker syndrome in children with hematuria.
Shin
Jae Il
JI
The Institute of Kidney Disease, Department of Pediatrics, Yonsei University College of Medicine, Severance Children's Hospital, Seoul, South Korea.
Park
Jee Min
JM
Lee
Jae Seung
JS
Kim
Myung Joon
MJ
D000293:Adolescent; D001783:Blood Flow Velocity; D002648:Child; D003251:Constriction, Pathologic; D005260:Female; D006417:Hematuria / Q000209:etiology; D006801:Humans; D007674:Kidney Diseases / Q000000981:diagnostic imaging; D008297:Male; D016491:Peripheral Vascular Diseases / Q000000981:diagnostic imaging*; D012082:Renal Veins / Q000000981:diagnostic imaging* / Q000473:pathology*; D013577:Syndrome; D018608:Ultrasonography, Doppler