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9. OBSTRUCTIVE PATHOLOGY OF RENAL DUPLICATION: URETEROCELE AND ECTOPIC URETER

^{9.1 BACKGROUND}

Ureterocele and ectopic ureter are the two main anomalies associated with a complete renal duplication. At present, antenatal ultrasonography detects both conditions in the majority of cases and diagnosis is confirmed at birth by physical examination, radiography and, occasionally, cystoscopy. In other cases, for example in adults, these anomalies are revealed by clinical symptoms: UTI, disturbances of micturition and urinary in­continence.

9.1.1 Ureterocele

Ureterocele is a cystic dilatation developed on the intravesical part of the ureter corresponding to the upper pole of a renal duplication. It is more frequent in females than in males, the overall prevalence being 1 in 4,000 births.

9.1.2 Ectopic ureter

Ectopic ureter is less frequent than ureterocele (1 in 40,000 births), but is again more common in females (male to female ratio, 1:5). Eighty percent of ectopic ureters are associated with a complete renal duplication.

In females, the ureteral orifice may be located:

• In the urethra, from bladder neck to meatus (35%)

• In the vaginal vestibule (30%)

• In the vagina (25%)

• In the uterus and Fallopian tube (rarely)

In males, the ureteral orifice may be located:

• In the posterior urethra above the verumontanum and never below the external sphincter (60%)

• In the seminal tract (vas deferens, ejaculatory ducts, seminal vesicles) (40%)