[A history of edema: advances in the pathogenesis and management]

The management of edematous patients has been a matter of medical concern from since the beginning of time. Richard Bright provided a new insight by recognizing the association of coagulable urine with disease of the kidneys. There had been much debate about the frequent dissociation between uremia and edema. Strauss revealed that in uremia without edema there was a retention of nitrogen metabolites, whereas in proteinuric edematous patients there was a retention of chloride and water. He concluded that edema was due solely to the retention of sodium chloride. Though underfilling theory was proposed as a possible mechanism for the development of edema in nephrotic syndrome and liver cirrhosis, several evidences against this theory have been reported in these 10 years. An intrarenal disturbance of sodium excretion related to the renal disease, liver diseases or heart failure may be the primary factors governing sodium retention. Further studies are necessary for better understanding of the mechanisms of the sodium and water retention in edema.