Objective: To summarize and analyze the clinical features and etiologies in hospitalized patients with syndrome of inappropriate antidiuretics (SIAD) during the past 25 years. Methods: All data of 128 patients with SIAD admitted to Chinese PLA General Hospital since January 1991 to January 2016 were collected. SIAD was diagnosed based on the 1957 criterion. Results: (1) The most frequent causes of increased inappropriate secretion of vasopressin were malignant tumors, lung diseases (e. g. pneumonia), and central nervous system diseases, in which malignant tumors accounted for 38.28% of the SIAD. (2) During the past 25 years, the proportion of malignant diseases declined from 4/7 to 35.29%, while, the proportion of pulmonary infection increased from 1/7 to 35.29% (P<0.05). (3) The patients with malignant tumors had the lowest serum sodium and serum osmolality among all SIAD patients. (4) CT scan had a high diagnostic value for chest and brain detection. (5) Among three SIAD subjects with unknown reasons at onset, two were diagnosed with small cell lung cancer and one with gastric cancer during follow-up. Conclusion: The etiology of SIAD is complex and it could be attributed to multifarious etiological factors. Malignant tumors account for the largest proportion of all patients, and pulmonary infection was ranked in second place. Cautions on tumors have to be taken when serum sodium of a SIAD patient is below 118.1 mmol/L.
目的： 总结抗利尿不适当综合征(SIAD)患者的临床资料，对不同病因的SIAD患者临床特点进行深入分析，以期对病因诊断提供依据。 方法： 收集1991年1月至2016年1月在解放军总医院住院并诊断为SIAD患者的临床资料，对其原发病因进行统计，分析总结不同病因SIAD患者特点。 结果： (1)SIAD患者原发病因构成复杂，主要分为5大类：恶性肿瘤疾病、肺部良性疾病、中枢神经系统疾病、药物及其他，其中恶性肿瘤疾病所占比例最高，为38.28%。(2)不同时间段SIAD患者的原发病因构成比例发生变化，随时间推移，恶性肿瘤疾病比例由4/7降至35.29%；而肺部良性疾病患者比例由1/7升至35.29%。(3)不同原发病因患者血钠、血渗透压水平存在差异(P<0.05)，恶性疾病患者血钠和血渗透压水平最低，分别为116.23 mmol/L和257.08 mmol/L。当血钠水平低于118.1 mmol/L时，其诊断肿瘤为致病原因的灵敏度为83.5%，特异度为59.2%。(4)胸部CT检查，对肺部良性疾病检出率最高，为70.41%；颅脑CT对中枢神经系统疾病检查阳性率最高，为63.16%；在全身检查中PET-CT对恶性肿瘤疾病的检出率最高，为76.00%。(5)3例不明原因SIAD患者在随诊时查出2例患有小细胞肺癌，1例患有胃癌。 结论： SIAD原发病因构成复杂，肿瘤多见，其次是肺部良性疾病，当SIAD患者血钠水平低于118.1 mmol/L时，应注意排查肿瘤的可能。.
Keywords: Etiology; Syndrome of inappropriate antidiuresis.