We previously noted particulate matter (PM) under polarizing light microscopy within the granulomas of patients diagnosed with sarcoidosis (Chest 2002;122:148S-149S). However, our preliminary research lacked a control group. Therefore, we designed this study to examine tissue samples for the presence of PM from patients without granulomas.
Tissues samples from patients diagnosed with sarcoidosis were retreived using slides routinely prepared and stored in Pathology Departments. Normal tissues were selected from among autopsy specimens at our University hospital. A single pathologist reviewed each tissue sample using: 1) light microscopy for the presence of granulomas, and 2) polarizing light microscopy for the presence of PM within the multinucleated giant cells of the granuloma. Results were expressed as a two-by-two table. This research project was approved by our University’s Institutional Review Board as an exempt protocol.
Eighty tissue samples from patients diagnosed with sarcoidosis and eighty normal tissue samples were studied by light microscopy and polarizing light microsccopy. Age and gender differences between the groups were not significant. The two-by-two Table below displays the Results. The majority of tissues in both groups had PM detected. The differences between the groups was not significant.
PM was noted in the majority of tissues from both patients diagnosed with sarcoidosis and from normals.
The ubiquitous nature of PM in tissues may result in granulomatous inflammation in patients diagnosed with sarcoidosis by PM contact, PM inhalation and/or PM ingestion. Granuloma formation appears to require the presence of host susceptibility causing a reaction to the PM. Future investigations of the etiology of sarcoidosis should include polarizing light examination of tissue for PM, identification of the chemical composition and structural heterogeneity of the PM, and new tests designed to identify host susceptibility to the PM.
Polarizable material +Polarizable material -Granulomatous Inflammation +, n = 8062%38%Granulomatous Inflammation -, n = 8080%20%
Navasuma Havaligi, None.