Pneumology Department, Avicenne Universitary Hospital, Bobigny, France.
Histology and Cytology Department, Tenon Universitary Hospital, Paris, France.
Semin Respir Crit Care Med. 2014 Jun;35(3):336-51. doi: 10.1055/s-0034-1381229. Epub 2014 Jul 9.
Sarcoidosis is a systemic disease of unknown cause characterized by the formation of immune granulomas which most often involve the lung and the lymphatic system. Sarcoidosis may encompass numerous different clinical presentations. Typical presentations often prompt a rapid diagnosis while in 25 to 50% of cases, diverse and less typical presentations may lead to delayed diagnosis. The mediastinopulmonary sphere is involved in 85 to 95% of cases, associated with extrapulmonary localizations in half of cases while extrapulmonary localizations without lung involvement may be seen in 5 to 15% of cases. Bilateral hilar lymphadenopathy is the most typical sign at chest radiography. Computed tomography (CT) is essential face for atypical manifestations of the disease to avoid confusion with differential diagnoses and, sometimes, comorbidities. CT typically evidences diffuse pulmonary perilymphatic micronodules, with a perilobular and fissural distribution and upper and posterior predominance, even when an atypical CT pattern is predominant. CT allows deciphering pulmonary lesions in cases of pulmonary fibrosis, pulmonary hypertension, and airflow limitation. Pulmonary function tests generally correlate with the overall disease process. Forced vital capacity is the simplest and most accurate parameter to reflect the impact of pulmonary sarcoidosis. Cardiopulmonary exercise testing helps in understanding the mechanism behind dyspnea of uncertain origin. Endoscopic transbronchial needle aspiration is an extra tool to support diagnosis in addition to more classical biopsy means. Bronchoalveolar lavage (BAL) may be used for individual patients while it is not really decisive for the diagnosis of sarcoidosis for most patients. Diagnosis relies on compatible clinical and radiological presentation, evidence of noncaseating granulomas and exclusion of other diseases with a similar presentation or histology. The probability of diagnosis at presentation is variable from case to case and may often be reinforced with time. Some investigations are mandatory at diagnosis to assess organ involvement and disease activity. However, there are important variations in diagnostic work-up due to diverse expressions of sarcoidosis and differences in clinical practices among physicians.
结节病是一种病因不明的全身性疾病，其特征是形成免疫性肉芽肿，这些肉芽肿最常累及肺和淋巴系统。结节病可能包含许多不同的临床表现。典型的表现通常会促使快速诊断，而在 25%至 50%的病例中，不同和不太典型的表现可能导致延迟诊断。纵隔肺球在 85%至 95%的病例中受累，一半的病例伴有肺外局部病变，而 5%至 15%的病例可能出现无肺受累的肺外局部病变。胸部 X 线摄影显示双侧肺门淋巴结肿大是最典型的征象。计算机断层扫描（CT）对于疾病的非典型表现至关重要，可以避免与鉴别诊断混淆，有时还可以避免与合并症混淆。CT 通常表现为弥漫性肺周围微结节，呈小叶和裂分布，以上部和后部为主，即使 CT 表现不典型。CT 可以在肺纤维化、肺动脉高压和气流受限的情况下辨别肺部病变。肺功能检查通常与疾病的整体过程相关。用力肺活量是反映肺结节病影响的最简单和最准确的参数。心肺运动试验有助于理解来源不明呼吸困难的机制。经支气管镜针吸活检是除更经典的活检手段外的额外诊断工具。支气管肺泡灌洗（BAL）可用于个别患者，但对于大多数患者的结节病诊断并不具有决定性。诊断依赖于相符的临床和影像学表现、非干酪样肉芽肿的证据，以及排除具有相似表现或组织学的其他疾病。在初次就诊时的诊断可能性因病例而异，随着时间的推移可能会得到加强。一些检查在诊断时是强制性的，以评估器官受累和疾病活动。然而，由于结节病的不同表现和医生之间的临床实践差异，诊断工作存在很大差异。
