淋巴结由网状内皮细胞和淋巴组织组成,主要参与单核巨噬细胞系统对细菌、异物的吞噬,产生免疫抗体及淋巴细胞,参与髓外造血。病理性淋巴结肿大原因多为感染,过敏、肿瘤、血液病、结缔组织病等。急性淋巴结肿大:(1)急性单纯性淋巴结炎。常有感染病灶,如头皮感染引起枕部、耳后淋巴结肿大,腿外伤或 Lymph nodes by the reticuloendothelial cells and lymphoid tissue, mainly involved in mononuclear macrophage system of bacteria, foreign body phagocytosis, the production of immune antibodies and lymphocytes, participate in extramedullary hematopoiesis. Pathological lymph nodes are mostly due to infection, allergies, cancer, blood diseases, connective tissue disease. Acute lymph node enlargement: (1) Acute simple lymphadenitis. Often infected lesions, such as scalp infection caused by the occipital, ear lymph nodes, leg trauma or