Lymphadenitis

Etiology and pathways of infection entry

Lymphadenitis does not occur on its own. It develops against the background of pre-existing purulent-inflammatory diseases, such as infected wounds, furuncles, carbuncles, felon (panaritium), erysipelas, osteomyelitis, thrombophlebitis, or trophic ulcers. In addition, the cause may be specific infections, including tuberculosis, plague, and actinomycosis.

The main pathogens are pyogenic microorganisms. Infection can enter the lymph nodes via three pathways:

• Lymphogenic — the most frequent and primary pathway, when pathogens migrate through lymphatic vessels from the primary focus.
• Hematogenous — extremely rare, the infection is borne by the bloodstream.
• Contact — direct spread of inflammation from surrounding affected tissues.

Stages of development and clinical presentation

Inflammation of the lymph nodes often occurs simultaneously with lymphangitis. General symptoms include tenderness and noticeable enlargement of the nodes themselves, as well as signs of intoxication: headache, weakness, general malaise, and fever.

The pathological process goes through several consecutive stages, each with its own distinctive clinical signs:

1. Serous edema (simple or catarrhal lymphadenitis). The patient's general condition is little affected. Locally, a dull pain is noted in the region of regional nodes. On palpation, the nodes are enlarged, dense, and painful. An important diagnostic sign: the nodes are not fused to surrounding tissues (retain mobility), and the skin over them is unchanged.
2. Purulent lymphadenitis. The pain becomes sharp and intense. The skin over the affected area is hyperemic, palpation is sharply painful. The lymph nodes fuse both with each other and with underlying tissues, making them fixed.
3. Adenophlegmon. Represents purulent inflammation of the surrounding tissues. Locally, diffuse skin hyperemia is observed and a dense infiltrate without clear boundaries is formed. The patient's general condition becomes severe: high fever, chills, tachycardia, and pronounced weakness are characteristic.

Special forms, complications, and treatment

Putrid phlegmon is singled out separately, in which crepitus (a characteristic crunch) is determined on palpation in the lesion focus.

If the process is not stopped, severe complications arise. Purulent inflammation can spread to deep cellular spaces (e.g., retroperitoneal space or mediastinum), and in extreme cases lead to systemic infection — sepsis.

Surgical treatment is indicated when the disease transitions to the purulent stage (formation of abscesses or adenophlegmon). Surgical tactics consist of opening abscesses, complete removal of purulent exudate, and mandatory wound drainage. Further management of such a patient is carried out strictly according to the general principles of treating purulent wounds.

Class and exam questions

What else to study on this topic

• Pathogenesis of pus spread into cellular spaces (mediastinum, retroperitoneal space)
• Specific lymphadenitis: clinical features in tuberculosis, plague, and actinomycosis
• Principles of local treatment of purulent wounds after opening adenophlegmon
• Relationship between lymphadenitis and lymphangitis in clinical practice

Other topics from the section "CHAPTER 11. SURGICAL INFECTION (PURULENT-INFLAMMATORY DISEASES)"

Prepared by WhiteCoat Pro faculty in accordance with the medical school curriculum. For educational purposes only.