Lymph nodes are distributed throughout the body and are important immune organs of the body. Normal lymph nodes are mostly in the range of 0.2 to 0.5 cm and are often distributed in clusters. Each group of lymph nodes collects lymphatic fluid from the corresponding drainage area, such as the lymph nodes behind the ear and mastoid area collect lymphatic fluid within the scalp; the submandibular lymph node group collects lymphatic fluid from the floor of the mouth, buccal mucosa, gums, etc.; the cervical lymph nodes collect lymphatic fluid from the nose, pharynx, larynx, trachea, thyroid, etc.; the supraclavicular lymph node group collects lymphatic fluid from the esophagus, stomach and other organs on the left side, and the trachea, pleura and lung on the right side. The supraclavicular lymph node group collects lymphatic fluid from the upper part of the trunk, breast, chest wall, etc.; the inguinal lymph node group collects lymphatic fluid from the lower extremities and perineum. Understanding the relationship between the two is clinically important for determining the location and nature of the primary lesion.
Etiology.
1.Infection
Acute and chronic inflammation caused by pathogenic microorganisms, such as bacteria, viruses, rickettsiae, etc. cause such as acute cellulitis, purulent tonsillitis, gingivitis, infectious mononucleosis, scrub typhus, tuberculosis, etc.
2.Tumor
(1) Lymphoma.
(2) Various types of acute and chronic leukemia.
(3) Plasma cell tumors: multiple myeloma, primary macroglobulinemia.
(4) Tumor metastasis: lung cancer, gastric cancer, liver cancer, breast cancer, nasopharyngeal cancer, etc.
3.reactive hyperplasia
(1) necroproliferative lymphadenopathy.
(2) serum sickness and serum sickness-like reactions.
(3) Allergic subsepsis.
(4) systemic lupus erythematosus rheumatism, etc.
4.Abnormal cell proliferation and metabolism
(1) Langerhans histiocytosis (histiocytosis X)
(2) lipid deposition disease.
(3) nodular disease.
Diagnosis
1. Enlargement of one regional lymph node is called limited lymph node enlargement, which is mostly seen in non-specific lymphadenitis, lymph node tuberculosis and malignant tumor metastasis, and the primary lesion should be sought according to the lymphatic drainage area. Enlarged lymph nodes in more than two areas should be considered as systemic lymph node enlargement, mostly seen in acute and chronic lymphadenitis, infectious mononucleosis, leukemia, lymphoma, leptospirosis, scrub typhus, brucellosis, serum sickness, connective tissue disease, etc.
2.Concomitant symptoms can provide important clues to the etiology of lymph node enlargement.
(1) If the enlarged lymph nodes are accompanied by foci of infection in the corresponding drainage area, such as enlarged lymph nodes under the jaw and chin with tonsillitis and gingivitis, enlarged lymph nodes in the axilla with mastitis, enlarged lymph nodes behind the ear with scalp infection, enlarged lymph nodes in the left inguinal area with left lower extremity dermatitis, it can be diagnosed as non-specific lymphadenitis.
(2) Swollen lymph nodes with pain are mostly caused by acute inflammation, often with local redness, swelling, heat and other inflammatory manifestations; while painless swollen lymph nodes are commonly found in malignant tumors metastatic lymphoma, etc. Local lymph node enlargement with low fever, night sweating and weight loss suggests lymph node tuberculosis, malignant lymphoma or other malignant tumors.
(3) Enlarged lymph nodes with periodic fever are mostly seen in malignant lymphoma; generalized enlarged lymph nodes with fever are seen in infectious mononucleosis, leukemia, lymphoma, etc. Occasionally, they are seen in systemic lupus erythematosus.
(4) Swollen lymph nodes with skin rash are often seen in certain infectious diseases or allergic diseases, and lymphoma should also be alerted.
Treatment should be given according to different causes.