[Urinary dribbling in girls: which investigations in 2012?]. / Écoulement urinaire chez la fille: quelle imagerie en 2012?

ABSTRACT

Continuous urinary leakage, despite normal deliberate voiding, must suggest the diagnosis of ectopic ureter, more specifically in girls. Ectopic ureter is usually associated with duplex kidney and complete ureteral duplication. The strategy of investigations has changed over the past few years, due to MRI development in the analysis of urinary tract malformations. We report the case of a 4-year-old girl who presented with these symptoms and had a suspicion of left duplex kidney on the prenatal ultrasonography (US). Two US examinations during the first months of life were compatible with a left duplex kidney without any complication. Another US at the age of 4 years was reported as normal. We completed the investigation with MR urography, which revealed a left duplex kidney with a poorly functioning dysplastic upper pole, and the orifice of the ureter of this upper pole inserting in the vagina. The surgical treatment, realized by celioscopy, was partial nephrectomy of the upper pole, removing most of the ectopic ureter. US is the first exam to investigate urinary tract malformations. However, duplex kidney with small dysplastic pole and ectopic insertion of a nondilated ureter may be difficult to see, and a normal US should never end the investigations. Intravenous urography and renal scintigraphy used to be the reference complementary exams, but are now replaced by MR urography. Without using ionizing radiation, MR urography can visualize duplex kidney and ectopic ureteral insertion with high resolution, and evaluates renal function of each kidney and each pole. These morphological and functional data are essential to determine the surgical treatment.