摘要报道2例肾上腺皮质功能不全合并抗利尿激素分泌异常综合征(SIADH)所致顽固性低钠血症患者的临床资料,并进行相关文献复习.病例1确诊原发性肾上腺皮质功能不全27年,住院期间出现严重低钠血症,足量激素替代治疗无法纠正,进一步检查证实合并肺癌继发的SIADH,加用托伐普坦后血钠恢复正常.病例2确诊肺癌继发的SIADH,托伐普坦治疗后血钠正常,但化疗过程中再次出现顽固性低钠血症,复查皮质醇及ACTH水平降低,考虑合并药物继发的肾上腺皮质功能不全,糖皮质激素替代治疗后血钠恢复正常.原发性/继发性肾上腺皮质功能不全及SIADH均可导致严重低钠血症,二者并存非常少见,可能先后发生,临床诊断复杂.顽固性低钠血症鉴别诊断应想到二者并存的可能性,治疗中密切监测疗效,及时修正诊断,减少漏诊、误诊.

abstractsTo summarize the clinical data of two cases with severe hyponatremia diagnosed as adrenal insuffiency combined with syndrome of inappropriate secret on of antidiuretic hormone(SIADH),and to review related literatures.Case 1 diagnosed as Addison's disease for 27 years and developed severe hyponatremia again but did not response well to sufficient glucocorticoid.Further examination showed SIADH caused by lung cancer and tolvaptan worked well.Case 2 was diagnosed as SIADH caused by lung cancer and responsed well to tolvaptan.However,hyponatremia reoccurred with the decreasing level of ACTH and cortisol during the chemotherapy.It was thought that hyponatremia was caused by drug-related adrenal insuffiency and glucocorticoid replacement therapy achieved good response.Both primary/secondary adrenal insuffiency and SIADH can lead to severe hyponatremia,but it is rare that the two situations exist in one patient and occur in different time.We should consider the possibility of the situations when we make differential diagnosis of refractory hyponatremia,monitoring the curative effects carefully,then correct the diagnosis timely,and reduce missed diagnosis and misdiagnosis.