Alterations in the Permeability of Membranes During Infections

The underlying physiological disturbances responsible for death during the course of acute infections remain a mystery. Thousands of years ago men began to record descriptions of febrile illnesses. A particular type of rash might be accompanied by a slow or fast pulse and by a steady or remitting type of fever, which would run its course within a reasonably constant period of time and would be followed by a period of convalescence. On the basis of clinical observations, various specific diseases were separated from one another—the small from the great pox, the typhuslike, or typhoid, fever from typhus. In the course of some acute infections the appearance of edema was noted; in others edema was not visible, but diuresis occurred during recovery—an observation which suggested that fluid was retained in the tissues, whether it was obvious or not. With the introduction of immunologic techniques, it was recognized that the patient