Lysis

LYSIS, lysis (from Greek lyo—I loosen), one of the forms of the third period of fever (stadium decrementi), its subsidence. Lysis is characterized by a slow fall in temperature in contrast to a crisis (see). The gradual fall in temperature usually corresponds to the gradual fading of other symptoms caused by the given disease.

Figure 1.

Figure 2. Lysis characterizes the termination of most local infectious processes (bronchopneumonia, pleurisy, phlegmons, purulent parotitis, etc.). Among general acute infectious diseases, the third stage of typhoid fever can serve as an example of lysis. The temperature curve decreases either stepwise (Fig. 1) or by exhibiting strong fluctuations (Fig. 2). The difference between the evening and morning temperature reaches 2–3°. The period of such sharp temperature fluctuations is given the name of the amphibolic stage, or the stage of steep curves (steile Kurven). In this case, the morning temperature usually decreases much faster than the evening temperature, often falling to normal figures from the very beginning of lysis. Such sharp decreases in temperature are often accompanied by profuse sweating. Chills during subsequent temperature rises are observed much less frequently. The duration of lysis ranges from 3 days to 1.5–2 weeks. Lit.—see literature for the article Fever.