Sarcoidosis is a multisystem inflammatory disorder and can affect any organ; however, ureteric involvement is extremely rare with only four cases reported in the literature to date, all of which were diagnosed with surgical ureteral resection including a nephroureterectomy. This study reports the first case of ureteric sarcoidosis controlled with medical therapy where a differential diagnosis was performed based on the diagnostic clue of hypercalcemia. A definitive diagnosis was established without surgical resection of the ureter. A 60-year-old man presented with anorexia and weight loss. Blood tests showed renal dysfunction and hypercalcemia. Computed tomography revealed left hydronephrosis associated with left lower ureteral wall thickening, which showed high signal intensity on diffusion-weighted magnetic resonance imaging. Similarly, we detected a bladder tumor on cystoscopy, and a 2-cm-long stenosis was revealed by retrograde ureterography; therefore, ureteral cancer was suspected. Meanwhile, considering the clinical implication of hypercalcemia, a differential diagnosis of sarcoidosis was established based on elevated levels of sarcoidosis markers. Fluorodeoxyglucose positron emission tomography showed fluorodeoxyglucose accumulation in the left lower ureter, skin, and muscles, suggestive of ureteric sarcoidosis with systemic sarcoid nodules. For a definitive diagnosis, transurethral resection of the bladder tumor and ureteroscopic biopsy were performed. Histopathological examination revealed ureteric sarcoidosis with bladder urothelial carcinoma. Following an oral administration of prednisolone, hypercalcemia instantly resolved, the renal function immediately improved, and the left ureteral lesion showed complete resolution with no recurrence. In this case, the co-occurrence of ureteral lesion with bladder tumor evoked a diagnosis of ureteral cancer. However, considering a case of ureteral lesion complicated with hypercalcemia, assessment for differential diagnosis was performed based on the calcium metabolism and sarcoidosis markers. In cases of suspected ureteric sarcoidosis from the assessment, pathological evaluation with ureteroscopic biopsy should be performed to avoid nephroureterectomy.

中文翻译：

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输尿管结节病合并膀胱尿路上皮癌并发高钙血症的相关性：病例报告。

结节病是一种多系统炎症性疾病，可以影响任何器官；然而，输尿管受累极为罕见，迄今为止文献中仅报道了 4 例病例，所有病例均被诊断为手术输尿管切除术，包括肾输尿管切除术。本研究报告了首例药物治疗控制的输尿管结节病病例，该病例根据高钙血症的诊断线索进行鉴别诊断。无需手术切除输尿管即可确诊。一名 60 岁男性因厌食和体重减轻就诊。血液检查显示肾功能不全和高钙血症。计算机断层扫描显示左侧肾积水伴左输尿管下壁增厚，弥散加权磁共振成像显示高信号强度。相似地，我们在膀胱镜检查中发现了一个膀胱肿瘤，逆行输尿管造影显示了一个 2 厘米长的狭窄；因此怀疑是输尿管癌。同时，考虑到高钙血症的临床意义，基于结节病标志物水平升高建立了结节病的鉴别诊断。氟脱氧葡萄糖正电子发射断层扫描显示左下输尿管、皮肤和肌肉有氟脱氧葡萄糖积聚，提示输尿管结节病伴全身结节。为了明确诊断，进行了膀胱肿瘤的经尿道切除术和输尿管镜活检。组织病理学检查显示输尿管结节病伴膀胱尿路上皮癌。口服泼尼松龙后，高钙血症立即消退，肾功能立即好转，左侧输尿管病变完全消退，无复发。在这种情况下，输尿管病变与膀胱肿瘤的共同发生引起了输尿管癌的诊断。然而，考虑到一例输尿管病变并发高钙血症，根据钙代谢和结节病标志物进行鉴别诊断评估。如果评估结果怀疑输尿管结节病，应通过输尿管镜活检进行病理评估，以避免肾输尿管切除术。基于钙代谢和结节病标志物进行鉴别诊断的评估。如果评估结果怀疑输尿管结节病，应通过输尿管镜活检进行病理评估，以避免肾输尿管切除术。基于钙代谢和结节病标志物进行鉴别诊断的评估。如果评估结果怀疑输尿管结节病，应通过输尿管镜活检进行病理评估，以避免肾输尿管切除术。