RESUMO
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.