淋巴结属于免疫器官,淋巴结内的细胞成分主要是淋巴细胞和网状内皮细胞(组织细胞)。人体内大大小小的淋巴结有500～600个之多,淋巴结的大小,从数毫米到2厘米不等。新生儿的淋巴结发育不完全,例如缺乏结缔组织、分叶不清、滤泡未完全形成、淋巴结外面的包膜薄等。所以,在皮下组织中的淋巴结不易清楚地摸到。一直到1岁时才能在枕、颈、腹股沟及腋下摸到淋巴结。什么样的淋巴结才是正常的呢?首先不要认为一摸到淋巴结就是异常。淋巴结只在身体的浅表部位,如枕部、耳后、颈部、腹股沟、腋下等处可扪及。如果淋巴结的大小不超过豌豆,单个、质地柔软、可以移动、不粘连、无压痛,则属于正常情况,否则就是异常。淋巴结的肿大,可以分为局部淋巴结肿大及全身淋巴结肿大。各种病原体引起的感染,血液病、代谢性疾病、过敏反应、结缔组织病、肿瘤等疾病都可造成全身淋巴结肿大。局部淋巴结肿 Lymph nodes belong to the immune organs, and the components of the lymph nodes are mainly lymphocytes and reticuloendothelial cells (tissue cells). Large and small human body lymph nodes as many as 500 to 600, the size of lymph nodes, ranging from a few millimeters to 2 centimeters. Neonatal lymph node development is not complete, such as the lack of connective tissue, unclear lobes, follicles are not fully formed, thin outer coating of lymph nodes. Therefore, the lymph nodes in the subcutaneous tissue is not easily found clearly. Until the age of 1 years in the pillow, neck, groin and underarm touch the lymph nodes. What kind of lymph nodes is normal? First do not think that touched the lymph nodes is abnormal. Lymph nodes only in the superficial parts of the body, such as occipital, ear, neck, groin, underarm palpable. If the size of lymph nodes does not exceed pea, single, soft texture, can move, do not block, no tenderness, then it is normal, otherwise it is abnormal. Lymph nodes enlargement, can be divided into local lymph nodes and systemic lymphadenopathy. Various pathogens caused by infection, blood diseases, metabolic diseases, allergic reactions, connective tissue disease, cancer and other diseases can cause systemic lymphadenopathy. Local lymph nodes