Clinical Misdiagnosis Analysis of Renal Calyceal Diverticulum

ZOU Yihua; LI Jing; ZHANG Wei

doi:10.3969/j.issn.1002-3429.2025.09.006

Abstract：Objective To investigate the clinical characteristics,causes of misdiagnosis and preventive measures of calyceal diverticulum(CD).Methods The clinical data of a patient with CD who was misdiagnosed as simple renal cyst be-fore operation and admitted to hospital in June 2021 were retrospectively analyzed.Results The patient was admitted to hos-pital due to ＂left renal cystic mass found in physical examination for 1 week＂,and no contrast agent was found to enter the cystic cavity during the excretory phase of enhanced CT scan.He was diagnosed as a simple renal cyst before operation.The cyst fluid was extracted during renal cyst decompression for qualitative protein test,which was negative,and 20 mg furosemide was injected intravenously to reduce pneumoperitoneum pressure to 5 mmHg.Examination of the bottom of the cystic cavity showed clear fluid flowing from the neck of the diverticulum,and the operation was changed to cervical incision of CD and di-verticulectomy.The histopathological examination confirmed the presence of CD.The patient was discharged from hospital af-ter recovery from the operation.The misdiagnosis lasted 2 d.After 3 years of follow-up,the patient showed no discomfort symptoms and the volume of CD decreased significantly.Conclusion CD lacks specific clinical manifestations and is easily misdiagnosed as simple renal cyst.Contrast-enhanced CT with a delayed 60-min excretory phase scan is a good diagnostic method for CD,but there is still a possibility of false negativity.Qualitative test of cyst fluid protein and quantitative detection of cyst fluid creatinine can be used as effective remedies for identifying CD during operation.