Lymphadenitis definition: Acute inflammation of the lymph nodes caused by the spread of purulent bacteria through the lymphatic vessels to the lymph nodes in the region to which they belong. However, lymphadenitis does not occur in everyone who encounters bacterial infections, but only when the body’s resistance is reduced. Lymphadenitis is likely to occur after bacterial infection when resistance is significantly reduced by long-term malnutrition, anemia and other chronic diseases.
Etiology: The pathogenic bacteria are mostly Staphylococcus aureus and Streptococcus haemolyticus. A few of them are Pseudomonas aeruginosa and Escherichia coli.
Prevalent sites: Acute lymphadenitis in pediatric patients is mostly seen in the neck.
1. the site of occurrence of cervical lymphadenitis is closely related to the anatomical location of the lesion and the extent of lymphatic drainage.
2. tonsillitis and dental caries can lead to submandibular lymphadenitis
3. scalp infections causing lymphadenitis in the posterior occipital, preauricular and posterior portions of the ear
4, incisor and sublingual infections cause subchin lymphadenitis.
5. infections of the upper extremities, chest wall, back and abdominal wall above the umbilicus, which can cause axillary lymphadenitis
6. Infections of the lower extremities, the abdominal wall below the umbilicus, the perineum and the buttocks cause inguinal lymphadenitis.
Pathology: In acute lymphadenitis, the lymph nodes are congested and swollen with leukocyte infiltration and inflammatory exudate, and when the condition worsens, the center of the lymph nodes are degenerated, necrotic and purulent, with inflammatory thickening of the peritoneum. The infection spreads to the periphery and forms perilymph node inflammation. Multiple lymph nodes become infected and adhere to form a mass, sometimes developing into cellulitis. After the infection is controlled, the inflammation gradually limits or subsides, and sometimes an abscess may form.
Clinical manifestations: Early lymph node enlargement, localized redness, swelling, and pressure pain, still movable. After the inflammation increases, the redness and swelling may spread to the periphery and a local mass may appear, which cannot be moved. Systemic reactions may include chills, fever, loss of appetite, and lack of spirit. Acute submandibular lymphadenitis in infants and children is a strong response to inflammation, often manifesting as cellulitis, with heavy local tissue inflammation and a marked systemic toxic reaction. It may manifest as extensive swelling and elevation of local soft tissues, redness, severe pain and pressure, and in severe inflammation it may involve the whole submaxillary area, and some of them may affect the opposite side or even the whole anterior neck. A throbbing sensation occurs when suppuration occurs, and systemic symptoms such as fever, headache, malaise, and loss of appetite are evident. Submandibular lymphadenitis may sometimes spread to the lateral wall of the pharynx or form an abscess in the posterior pharyngeal wall, and occasionally may compress the larynx causing cyanosis and dyspnea.
Differential diagnosis.
1, tuberculous lymphadenitis: the onset of the disease is slow, the child may have wasting, weakness, lymph node adhesions into clusters that do not subside for a long time, tenderness and swelling is not as obvious as lymphadenitis. The blood sedimentation is accelerated, the tuberculin test is positive, and antacid bacilli can be found in the puncture pictures.
2, acute mumps: lymphadenitis in the subauricular region should be distinguished from it. When suffering from mumps, the mucous membrane of the opening of the parotid ducts in the cheek is swollen, there is pressure pain in the parotid area, the skin is not red or swollen, the swelling is more diffuse, and there are no local nodules.
3. Gill-derived cysts with infection: submandibular lymphadenitis is easily confused with the latter, which is located at the anterior border of the sternocleidomastoid muscle and is mostly present after birth.
4, Hodgkin’s disease: the whole body lymph nodes are involved, but the cervical lymph nodes are enlarged earlier, the liver and spleen are also enlarged, the enlarged lymph nodes are scattered and movable, the texture is hard, no obvious pressure pain, and the boundary is clear. Mediastinal lymph nodes were seen to be enlarged on chest X-ray. Puncture biopsy or bone marrow aspiration can clarify the diagnosis.
5, BCG reactive lymphadenitis: lymph node enlargement mostly occurs several months after BCG vaccination, and there are more ipsilateral axillary lymph node enlargement in shoulder vaccinated patients, and local lymph node enlargement is painless, with some tissue liquefaction to form cold abscess. Sometimes purulent infection occurs and the lymph nodes become red, swollen, and ruptured, and pus flows out.
Treatment.
1, early with non-surgical methods, systemic application of antibiotics, local hot compresses, external use of ichthyolite ointment.
2.If the inflammation is limited to form abscess, it should be promptly incised and drained.