Silicosis is an incurable occupational interstitial lung disease caused by free crystalline silica inhalation and its accumulation in the lung interstitium
. Variable forms of the disease can be identified, but mainly three can be identified: chronic/classic, accelerated, and acute.
The primary mechanism driving fluid clearance from the alveolus is the active transportation of Na + ions from airspaces into the lung interstitium
. This solute transportation drives osmotic water transportation and accordingly alveolar fluid clearance (AFC). Na + ions enter alveolar epithelial cells at the apical surface, primarily through amiloride-sensitive sodium channels, such as the epithelial sodium channel (ENaC), and are pumped out on the basolateral surface by Na, K-ATPase.,, Furthermore, the cystic fibrosis transmembrane conductance regulator (CFTR) and aquaporins are also important in mediating the AFC.
The presence of B-lines in lung ultrasound imaging indicates increased fluid contents in lung interstitium
Lung ultrasound can detect extravascular lung water (EVLW), fluid present in lung interstitium
, which is strongly dependent on the left ventricle filling pressure .
By definition, IM are located in the lung interstitium
, while AM reside in the airway lumen.
As far as etiopathogenesis is concerned, some studies put forward the hypothesis that inflammation may be an early event in ILD with the recruitment of immune cells to the lung interstitium
, followed by epithelial and endothelial damage.
This pattern may also suggest a more aggressive infiltrative growth into the lung interstitium
, depicted histopathologically by infiltrative nodular proliferation of tumor cells within the vessel lumina [63, 64].
(1) The histologic pulmonary findings show calcium deposition in the lung interstitium
, alveolar septa and bronchial walls.
DISCUSSION: Interstitial lung diseases are heterogeneous group of diseases involving lung interstitium
. They have features in common like similarities of symptoms, comparable radiographic appearances, consistent alterations in the pulmonary physiology and typical histological features.
Local inflamed cells in the lung interstitium
activate the pulmonary capillary endothelium culminating in the expression of adhesion molecules on the endothelial cell .
In the case report, lung biopsies "demonstrated numerous spheroid silicone particles within the lung interstitium
and small pulmonary vessels, surrounded by foreign body giant cells and nonnecrotizing granulomatous inflammation," 4 years after the patient reportedly "traveled to Mexico for silicone injections in the breasts and buttocks."
Patients present with lymphocytosis and diffuse lymphocytic infiltration limited to the lung interstitium