At present, the diagnosis of body fluid leakage is mainly based on the presence of predisposing factors, clinical manifestations and laboratory tests, such as the presence of factors causing SIRS or sepsis, the presence of generalized edema, decreased blood pressure and central venous pressure, weight gain, hemoconcentration, hypoproteinemia, and more severe edema after supplementation with small molecule crystalloid substances can be clinically diagnosed as CLS, i.e. capillary leakage syndrome. The clinical differential diagnosis of this disease is as follows: 1. Idiopathic capillary leak syndrome: It is a rare CLS, originally reported in 1960 by Clarkson et al. It can be unprovoked, recurrent, and is a group of rare clinical syndromes with unexplained hypovolemic hypotension, hemoconcentration, nonproteinuric hypoproteinemia, generalized edema, and in most cases with heteroglobulinemia. . In severe cases, heart, lung, kidney and other vital organ failure can also occur and can progress to multiple myeloma with a high morbidity and mortality rate. However, lung and kidney capillaries are generally not involved during the attack. Terbutaline (β2 agonist) and theophylline can improve the symptoms and prevent its attack. 2. Interfascial compartment syndrome: history of trauma, significant local edema of trauma, no edema in other parts.