Phlegmon (phlegmona) – acute purulent inflammation of the soft tissues. It differs from an abscess in the absence of a purulent membrane. Depending on the localization, phlegmon can be epifascial (superficial), subfascial (deep) and specific (purulent mediastinitis, paranephritis, paraproctitis). If the infection spreads from the lymph nodes, then adenoflegmon is formed.
Etiology and pathogenesis of phlegmon
Phlegmon causative agents are a variety of microbes and their associations: aerobes, anaerobes, gram-positive and gram-negative, Escherichia coli, Proteus, enterobacteria, but most often – staphylococci, streptococci and bacteroids.
The development of phlegmon begins with serous infiltration of subcutaneous fat, which quickly melts with the formation of purulent exudate. After that, there are foci of necrosis that do not delimit, but tend to spread, especially along interfascial intervals.
The factors causing the occurrence of phlegmon are similar to those with an abscess, but a special role in this case is played by a decrease in macroorganism resistance, severe diabetes mellitus, high virulence of microorganisms, vitamin deficiencies, elderly patients, immunodeficiency, sub- and decompensation of the cardiovascular system.
The rapid appearance and spread of painful infiltrate, redness, local temperature increase, severe dysfunction of the affected tissue. Over time, there is extensive purulent softening, symptoms of general intoxication: fever up to 38-40 ° C, weakness, headache, lack of appetite, oliguria, leukocytosis with a shift in the blood count to the left, blanching of the skin, the appearance of a cold sweat, the patient’s passive position in bed, in severe cases – a dull consciousness. Lymphangitis develops, regional lymph nodes (lymphadenitis) increase. Complications may occur in the form of erysipelas, thrombophlebitis, arthritis, tendovaginitis, meningitis, sepsis.
With deep phlegmon of the limb, the size of the latter progressively increases, as evidenced by measuring the length of its perimeter in the dynamics of a centimeter tape and comparing the results with the length of the perimeter of a healthy limb. On palpation in the area of infiltrate, the patient feels a spilled, sharp pain, muscle contracture is found in him, a significant violation of the function of the limb is observed, as a result of which it takes a forced position. In this case , regional lymphadenitis often develops.
During the ultrasound, a hypoechoic formation is determined without clear contours and signs of blood circulation, tissue edema. With a diagnostic puncture, purulent exudate can be obtained, but it is necessary to take into account the deep (subfascial) placement of the pathological focus and the threat of damage to the blood vessel with a needle.
If the pathological process is localized on the neck, a phlegmon is formed with a characteristic minimum of general symptoms of intoxication and the presence of wood consistency infiltrate . The color of the skin over the infiltrate is cyanotic. Infiltrate is almost not painful, soldered to the skin and deeply located tissues, as a result of which it is almost motionless and increases slowly. Suppuration of infiltrate occurs relatively rarely. The course of the disease is gradual, slow, the body temperature is subfebrile.