Abstract
Purpose: :
To quantify the dendritic cell content, the distribution of macrophage lysosomal CD 68 positive cells and the extent of internal elastic lamina (IEL) disruption in giant cell arteritis (GCA).
Methods: :
This was a histological retrospective study of archival paraffin embedded temporal artery sections comparing biopsy positive GCA (n=50) and age matched biopsy negative controls (n=50). Dendritic cell (DC) numbers and CD 68+ cell distribution were assessed using antibodies to S–100 and CD 68 antigens. IEL disruption was analysed by elastic Van Gieson (EVG) stain. Statistical analysis of data was by Mann–Whitney test.
Results: :
A significant increase in median counts of S–100+ cells, were observed in GCA (P=0.0001) compared to controls. CD 68+ staining distribution correlated well with that of S–100 + cells but with more numerous and confluent pattern in GCA sections and no staining detected in controls. Chi–square analysis revealed a significant increase in extent of IEL disruption in GCA (P<0.0001).
Conclusions: :
S–100+ cell population is increased with a parallel and a larger influx of lysosomal CD 68+ cells in GCA. Resident S–100+ cell numbers show minimal variation compared to larger variability of S–100+ response in GCA. IEL disruption is a significant finding in GCA, which is mostly segmental and confined to the area of inflammatory infiltration.
Keywords: pathology: human • vascular occlusion/vascular occlusive disease • neuro-ophthalmology: optic nerve