Grading nephroureteral dilatation detected in the first year of life: correlation with obstruction.
To understand better the significance of pediatric idiopathic nephroureteral dilatation the renal ultrasound images of patients less than 1 year old with hydronephrosis or hydroureteronephrosis were graded and compared to the radiological diagnosis of obstruction as determined by diuresis renography and/or urography. The study included 73 boys and 30 girls with hydronephrosis (76 patients) or hydroureteronephrosis (27). For hydronephrosis obstruction was diagnosed in 56 children (74%) and involved 61 of 97 kidneys (63%). For obstructed kidneys the mean grade of hydronephrosis (3.4 +/- 0.7 standard deviation) was statistically different from that of nonobstructed kidneys (1.6 +/- 0.8 standard deviation) (p less than 0.05). When the value to predict obstruction was set at grade 3 hydronephrosis or greater there was an 88% sensitivity and 95% specificity. For hydroureteronephrosis obstruction was diagnosed in 15 of 27 children (56%) and involved 17 of 34 kidneys (50%). The degree of dilatation was weighted as a score to assess the grades of hydronephrosis and ureteral dilatation, namely hydroureteronephrosis score equals grade of hydronephrosis plus grade of ureteral dilatation. In obstructed megaureters the mean hydroureteronephrosis score (5.8 +/- 1.0) was statistically different from that for nonobstructed megaureters (mean hydroureteronephrosis score 2.7 +/- 1.9) (p less than 0.001). When the value to predict obstruction was set at hydroureteronephrosis score of 5 or greater there was a 94% sensitivity and 80% specificity. Although ultrasound examination alone cannot be used to diagnose urinary obstruction, the radiological diagnosis of obstruction is linked with the grade of hydronephrosis or score of hydroureteronephrosis.
Maizels
M
M
Department of Radiology, Children's Memorial Hospital, Chicago, Illinois.
Reisman
M E
ME
Flom
L S
LS
Nelson
J
J
Fernbach
S
S
Firlit
C F
CF
Conway
J J
JJ
D000367:Age Factors; D004108:Dilatation, Pathologic; D005260:Female; D006801:Humans; D006869:Hydronephrosis / Q000175:diagnosis / Q000209:etiology / Q000473:pathology*; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D011859:Radiography; D014463:Ultrasonography; D014513:Ureter / Q000000981:diagnostic imaging / Q000473:pathology*; D014517:Ureteral Obstruction / Q000150:complications / Q000473:pathology*