Sarcoidosis

Author(s): Grunewald J, Grutters JC, Arkema EV et al

Nat Rev Dis Primers 2019; 5: 49

Interstitial lung diseases
General respiratory patient care

Digest Author(s): Stylianos Loukides, e-Learning Director / 1 December, 2019

Sarcoidosis is an inflammatory disease characterized by the presence of granulomas in virtually any organ, although the lung is the predominant site. The incidence of sarcoidosis depends on multiple parameters like geographic regions, gender, age and ethnicity. Genetic related factors as well as life style and enviromental factors contribute ot its pathogenesis. The mortality rate is low and is partially related to the underlying severity. Sarcoidosis is associated with increased risk of several co-morbidities like infections, CHF, DVT, and autoimmune diseases (autoimmune thyroiditis, Sjogren syndrome).

Summarizing the pathogenetic mechanisms we can order the events as following: exposure to antigen, initiation of an an innate immune response, interaction between antigen- presenting cells and local T cells, triggering of pro- inflammatory cytokine production, activation of B cells and development of a humoral response, the latest aids in the initiation and maintenance of granuloma formation and progression of granulomas to chronic inflammation and fibrosis or granuloma resolution in some patients.

Diagnosis depends on a multifunctional process consisting of clinical findings, radiological findings, differential diagnosis and evidence of a non- necrotizing granuloma in any affected site. Sarcoidosis affects multiple organs and is also associated with some systemic clinical features like fatigue and reduced mental health. 18F- FDG-PET represents a valuable diagnostic tool in terms of pulmonary and cardiac sarcoidosis.

Treatment of Sarcoidosis is highly variable. it is almost difficult to predict the disease behaviour. A spontaneous resolution potentially occurring even in those with advanced disease. So we are in the dilemma to wait and see or to initiate pharmacological therapy which is mainly based on steroids. In the current manuscript a proposed algorithm is available. This algorithm is based on two directions. The first one is the discrimination of symptoms caused by inflammation from those caused by permanent, non- progressing defects.

Comment

Three major points: The disease is characterized by heterogeneity. The disease assessment needs a multidisciplinary and multifactorial approach.When you are in the position to decide therapeutic interventions always consider the approach of ''wait and see''.