结节病（英文：Sarcoidosis，来自单词sarc，“肉体”的意思，并加上后缀-oid表示“像..似的”或“有质量的”，与后缀-osis,“疾病或非正常情况”的意思）英文中有时也被叫做sarcoid（简称），贝-伯病（Besnier-Boeck disease）或者贝-伯-肖三氏病（Besnier-Boeck-Schaumann disease），它是一种由许多异常的团状慢性炎症细胞（肉芽肿）所致多器官结节的情况。 造成结节病的原因目前暂不清楚。肉芽肿的出现往往不意味着坏死性病变，而是大部分肉芽肿坐落于肺或者淋巴结，但几乎所有的器官都可能会受到影响。通常来讲，发病是逐步的。 结节病的表现可以无症状或者慢性症状。它的症状通常自发地改善或者消失了。超过三分之二的结节病病人在9年后也没有任何症状。大约50%的人会复发。约10%的人会造成严重残疾。肺的瘢痕组织形成或肺部感染可导致呼吸衰竭而死亡。慢性患者可能会伴随多年的反复发作的症状。

Sarcoidosis, also called sarcoid, is a disease involving abnormal collections of inflammatory cells that form lumps known as granulomas. The disease usually begins in the lungs, skin, or lymph nodes. Less commonly affected are the eyes, liver, heart, and brain. Any organ, however, can be affected. The signs and symptoms depends on the organ involved. Often there are no or only mild symptoms. When it affects the lungs there may be wheezing, cough, shortness of breath, or chest pain. Some may have Lofgren's syndrome in which there is fever, large lymph nodes, arthritis, and a rash known as erythema nodosum.