METHODS: A 64-year-old man was admitted for limb weakness and facial hyperpigmentation for 2 weeks. Lab tests revealed intractable hypokalaemia (lowest at 1.8 mmol/L) and metabolic alkalosis. The diagnosis of RM was based on a creatine kinase(CK)level of 5 times the upper limit. The elevated CK and myohemoglobin (Mb) levels returned to within the normal range after the alleviation of hypokalaemia. The patient was diagnosed with ACTH-dependent Cushing\'s syndrome (CS) based on unsuppressed serum cortisol after a low-dose dexamethasone suppression test(LDDST) and remarkably elevated ACTH levels. The diagnosis of EAS was made based on the results of a high-dose dexamethasone suppression test(HDDST) and bilateral inferior petrosal sinus sampling(BIPSS). Multiple lymph nodes in the left supraclavicular fossa, right root of neck, mediastinum and bilateral hili of the lung were found with abnormal uptake of 68Ga-DOTA-NOC. Mediastinoscopic lymph node biopsy was performed. The pathological diagnosis was small-cell and large-cell neuroendocrine carcinoma with positive ACTH staining. The patient was prescribed mifepristone and received one cycle of chemotherapy. The patient could not tolerate subsequent chemotherapy and died of dyscrasia.
CONCLUSIONS: RM is a rare complication of EAS with insidious onset and atypical clinical manifestations. Serum potassium levels should be vigilantly monitored to avoid RM in EAS.
方法:一名64岁男性因肢体无力和面部色素沉着过度入院2周。实验室检查显示顽固性低钾血症(最低为1.8mmol/L)和代谢性碱中毒。RM的诊断是基于5倍上限的肌酸激酶(CK)水平。低钾血症缓解后,升高的CK和肌血红蛋白(Mb)水平恢复到正常范围内。根据低剂量地塞米松抑制试验(LDDST)后未抑制的血清皮质醇,患者被诊断为ACTH依赖性库欣综合征(CS),并且ACTH水平显着升高。EAS的诊断是根据大剂量地塞米松抑制试验(HDDST)和双侧岩下窦采样(BIPSS)的结果进行的。左侧锁骨上窝多发淋巴结,右颈根,发现纵隔和肺的双侧hili异常摄取68Ga-DOTA-NOC。纵隔镜淋巴结活检。病理诊断为小细胞和大细胞神经内分泌癌,ACTH染色阳性。患者服用米非司酮并接受一个周期的化疗。患者无法耐受随后的化疗,并死于手术不良。
结论:RM是EAS的罕见并发症,起病隐匿,临床表现不典型。应警惕监测血清钾水平,以避免EAS中的RM。