Phlegmon - the diffuse purulent inflammation of tissues with the tendency to advance. Distinguish superficial and deep phlegmons. Depending on layers which are amazed with a phlegmon, speak about a hypodermic, subfascial or intermuscular phlegmon. The phlegmon can be formed and in a fat of a mediastinum, a retroperitoneal fat, thoracal and abdominal walls. The Contagium - streptococcuses, anaerobic and putrefactive microorganisms. Entrance infection atriums - more often wounds. Quite often phlegmons develop again, owing to the further diffusion of any primary purulent process - a furuncle, an anthrax, an osteomyelitis, etc.

Ligneous phlegmon - result of a becoming infected weakly virulent microorganisms of a bottom of a mouth and a stomatopharynx. Occurrence painless, « firm, as a board », an infiltrate of soft tissues of a neck is characteristic. At a cut jelly-like tissues and insignificant quantity of a dark exsudate are defined.

Putrefactive phlegmon - especially serious form of disease. The major originators are E. coli. Within the first day rise in temperature, a pain and formation of a serous exsudate is marked, then the necrosis of the tissues, coming to the end an ichorization, from here the serious toxic phenomena quickly joins.