Clinical consideration of diagnosis mainly included the impression comparison method, comprehensive analysis and stepwise elimination method, among them, comprehensive analysis and stepwise elimination method were commonly used.The clinicians should be familiar with the causes of related diseases.They could mixed the basic medical knowledge and clinical medical knowledge together from the perspective of translational medicine, that is, with physiological and biochemical perspective, understanding and thinking about the produce, secrete, function and elimination of material and hormone in endocrine and metabolic diseases and distinguishing the causes of disease.To distinguish the causes of hyponatremia, the clinicians should know the water and sodium metabolism from the consideration of translational medicine.