소아 방광요관역류의 '잃어버린' 원인 : 요도 형태의 이상

Abstract

Purpose: To emphasize the significance of urethral abnormalities as the cause of vesicoureteral reflux in children. Materials and Methods: Current literatures were evaluated and the data in my laboratories were added. Results: Vesicoureteral reflux in boys which is more common in neonates and infants, has the tendency of quicker spontaneous resolution compared to girls in spite of its bilaterality and high grade. On the other hand, vesicoureteral reflux in girls, more commonly found after the first year of life, shows slower spontaneous resolution than boys although it shows lower grades when compared to boys. Such findings are attributed to sexual difference and the urethra is suspected to play an important role. The urethra influences the bladder function through sphincter to bladder reflex during the filling phase, and urethra to bladder reflex during the voiding phase. Cobb's collar which is an obstructive urethral lesion in males, is supposed to disappear after a short existence during fetal or neonatal period. However, if it causes severe obstruction or fails to disappear, it is suspected to result in the typical male type of vesicoureteral reflux caused by voiding dysfunction and increased intravesical pressure created by obstruction itself and urethral instability. Meanwhile, urethral abnormalities in girls such as mucosal web or female hypospadias causes vaginal voiding leading to dysfunctional voiding after toilet training and consequently results in vesicoureteral reflux through bladder instability, increased intravesical pressure and urinary tract infection as well as urethral instability. Conclusions: Since the meaning of surgery in vesicoureteral reflux, in view of kidney preservation, is becoming limited to the extent of recognizing the merit of surgical correction as merely discontinuing prophylactic antibiotics, studies of urethra in children with vesicoureteral reflux is another filed in (pediatric) urology which requires more active research and treatment.