RESUMO
INTRODUCTION: Ganglioneuroma is a rare benign nervous tumour frequently located in the retroperitoneal area. We report the case of a 22-year-old female patient where this tumour was revealed by nephritic colic complicated by pyelitis and kidney abscess. EXEGESIS: The patient presented with brutal feverish lumbar pains and urinary signs. Abundant iconography, in particular contrasted enhanced sonography, allowed to show a massive retroperitoneal lump and a puncture-biopsy indicated a ganglioneuroma which was surgically removed by laparotomy. Signs may be varied and misleading. Biological and radiological exams are useful for the diagnosis which can only be confirmed by the thorough histological examination of the removed sample. CONCLUSION: A large retroperitoneal lump without alteration of the patient's health should point to this diagnosis, since the complete surgical removal leads to recovery without recurrence, but all the other differential diagnoses must first be dismissed.