Objectives: To evaluate the efficacy of different imaging modalities for visualization of small poorly functioning hypoplastic and dysplastic kidneys and to assess the role of laparoscopy in localization and treatment.
Methods: Between 1998 and 2002, 10 female patients who presented with urinary incontinence, flank pain, or hypertension secondary to small, poorly functioning hypoplastic or dysplastic kidneys were treated at our institute. We reviewed the results of the imaging studies, cystoscopy, and evaluation under anesthesia for these patients. After the diagnosis, all patients were treated with laparoscopic retroperitoneal or transperitoneal nephroureterectomy or nephrectomy.
Results: Intravenous urography and ultrasonography failed to visualize the affected renal units in all 10 cases. Computed tomography could locate small dysplastic renal units in only 5 patients (50%). Dimercaptosuccinic acid renal scintigraphy was diagnostic in all 10 cases (100%). Magnetic resonance urography was done in 2 cases only, and the affected renal units were identified in both. Cystoscopy and vaginoscopy were inconclusive in all but 2 cases. Laparoscopy efficiently located the offending renal units in all 10 cases. In 9 cases, the affected renal units were located in the lumbar region, and in 1 case it was situated ectopically in the pelvis. All 10 patients underwent laparoscopic retroperitoneal or transperitoneal nephroureterectomy or nephrectomy and were asymptomatic after surgery.
Conclusions: Dimercaptosuccinic acid scintigraphy is an accurate and specific imaging modality for visualization of small hypoplastic renal units that are not visualized by conventional radiologic imaging techniques. Laparoscopy can be recommended as the ideal method of management, because it provides a minimally invasive technique for detecting the kidney and simultaneously correcting the problem.