Dermatologie, Hôpital Rothschild, AP-HP, Paris, France.
Sorbonne Université, UPMC Université Paris 06, Paris, France.
J Eur Acad Dermatol Venereol. 2019 Jan;33(1):198-203. doi: 10.1111/jdv.15167. Epub 2018 Jul 31.
Sarcoidosis, characterized by epithelioid granulomas, is considered to be caused by a complex interplay between genetics and environmental agents. It has been hypothesized that exogenous inorganic particles as crystalline silica could be a causal or adjuvant agent in sarcoidosis onset.
To investigate the location, frequency and physicochemical characteristics of foreign materials and mineral tissue deposits in the granulomatous area of cutaneous sarcoidosis.
Skin biopsies (n = 14) from patients diagnosed with cutaneous sarcoidosis (mean age 43 years; 11 patients with extracutaneous involvement) were investigated using polarized light examination (PLE), μFourier Transform Infra-Red (μFT-IR) spectroscopy and Field Emission Scanning Electron Microscopy coupled with Energy Dispersive X-ray Spectroscopy (FE-SEM/EDX).
Combined PLE, μFT-IR, FE-SEM/EDX analysis allowed to characterize mineral deposits in 7/14 biopsies (50%). It identified crystalline silica (SiO ) inside granulomas in three biopsies and calcite (CaCO ) at their periphery in 4.
This study emphasizes the need of using combined methods for assessment of mineral deposits in granulomatous diseases. According to the location and characteristics of deposits, we can hypothesize that SiO particles contribute to the granuloma formation, whereas CaCO deposits are related to the granuloma biology. However, the significance of the association between SiO deposits and sarcoidosis is still disputed.
结节病的特征是上皮样肉芽肿，被认为是遗传和环境因素复杂相互作用的结果。有人假设外源性无机颗粒，如结晶二氧化硅，可能是结节病发病的原因或辅助因素。
研究皮肤结节病肉芽肿区域中外来物质和矿物质组织沉积物的位置、频率和物理化学特性。
对 14 例经组织学诊断为皮肤结节病的患者（平均年龄 43 岁；11 例有皮肤外受累）进行皮肤活检，采用偏光显微镜检查（PLE）、μ傅里叶变换红外光谱（μFT-IR）和场发射扫描电子显微镜结合能量色散 X 射线光谱（FE-SEM/EDX）进行分析。
PLE、μFT-IR 和 FE-SEM/EDX 联合分析可对 7/14 例活检标本（50%）中的矿物质沉积进行特征化。在 3 例活检标本中发现了结晶二氧化硅（SiO2）存在于肉芽肿内，在 4 例活检标本中发现了方解石（CaCO3）存在于肉芽肿周围。
本研究强调了在肉芽肿性疾病中评估矿物质沉积时需要采用联合方法。根据沉积物的位置和特征，我们可以假设 SiO2颗粒有助于肉芽肿的形成，而 CaCO3沉积物与肉芽肿的生物学有关。然而，SiO2沉积与结节病之间的关联意义仍存在争议。
