Department of Endocrinology and Metabolism, The First Affiliated Hospital of Xi'an Jiaotong University, No.277 West Yanta Road, 710061, Xi'an, People's Republic of China.
Department of Endocrinology, The First Affiliated Hospital of Zhengzhou University, 450052, Zhengzhou, People's Republic of China.
BMC Endocr Disord. 2021 May 10;21(1):98. doi: 10.1186/s12902-021-00755-0.
Manifestations of hypokalaemia in ectopic adrenocorticotropic hormonesyndrome(EAS) vary from mild muscle weakness to life-threatening arrhythmia. Herein, we present a rare case of EAS with concomitant rhabdomyolysis(RM) as a result of intractable hypokalaemia.
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 Ga-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.
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.
异位促肾上腺皮质激素综合征（EAS）导致的低钾血症表现从轻度肌肉无力到危及生命的心律失常不等。在此，我们报告了一例罕见的 EAS 病例，由于难以纠正的低钾血症导致横纹肌溶解症（RM）。
一名 64 岁男性因四肢无力和面部色素沉着 2 周入院。实验室检查发现难治性低钾血症（最低 1.8mmol/L）和代谢性碱中毒。根据肌酸激酶（CK）水平升高 5 倍诊断为 RM。低钾血症缓解后，CK 和肌红蛋白（Mb）水平升高恢复正常范围。根据小剂量地塞米松抑制试验（LDDST）后血清皮质醇未被抑制和 ACTH 水平显著升高，该患者被诊断为 ACTH 依赖性库欣综合征（CS）。EAS 的诊断基于大剂量地塞米松抑制试验（HDDST）和双侧岩下窦采血（BIPSS）结果。左锁骨上窝、右颈根部、纵隔和双侧肺门发现多个淋巴结摄取 Ga-DOTA-NOC 异常。进行了纵隔镜淋巴结活检。病理诊断为小细胞和大细胞神经内分泌癌，伴 ACTH 染色阳性。患者被处方米非司酮，并接受了一个周期的化疗。但患者无法耐受后续化疗，最终死于血液系统疾病。
RM 是 EAS 的罕见并发症，起病隐匿，临床表现不典型。EAS 时应密切监测血清钾水平，避免发生 RM。
