Differential Diagnosis between Parapyelic Cyst and Pyeloureteral Junction: A Clinical Case Study

Abstract

Objectives: Intra-sinus renal cysts or parapyelic cysts represent a rare form of renal cysts. They are often associated with lower back pain. Symptomatic cases can be treated with percutaneous puncture and sclerotherapy, but due to the proximity to the renal hilum, the treatment of these cysts has undergone significant changes. Thus, percutaneous treatment has become contraindicated due to the potential for complications. While laparoscopic treatment appears to be the most suitable and effective technique, open surgery still has its indications, especially for large cysts and cases where there is diagnostic uncertainty along with an associated junction abnormality, as is the case in our study. Patients and Methods: We report a case of a right parapyelic cyst revealed by acute right pyelonephritis, with a diagnostic scan suggesting pyeloureteral junction syndrome secondary to a subpyelic crossing with an 8 cm parapyelic cyst, with contrast material passing into the cyst. Due to diagnostic uncertainty and operative difficulties under laparoscopy, a right lumbotomy was performed, allowing for the resection of an 8 cm parapyelic cyst and confirming the absence of an associated junction abnormality, without intraoperative complications. Results: 450 cc of citrine yellow fluid was recovered, with a permeable junction and absence of the lower polar vessel. Postoperative evolution was favorable both medically and surgically, with removal of the urinary catheter and JJ stent on postoperative day 5. Conclusion: Surgical treatment of parapyelic cysts through lumbotomy remains of interest as an effective approach, especially in cases of diagnostic uncertainty, with low morbidity and a short convalescence period.