Fig. 2

Histopathological examinations. a Specimen of the resected jejunum and mesentery: The mesentery includes significant nodular thickening (arrow). Each nodule has central canals composed of the vessel. b The arterial wall structure of GCA was broken, and all layers were not clear to distinguish. Hypertrophy of vascular intima is remarkable. Stenosis of the arterial lumen is mildly displayed. Multinucleated giant cells (arrow) are scattered on the endothelium, in the intima, media, and adventitia. Lymphocyte, neutrophils, and eosinophils are also infiltrated. c Elastica van Gieson stain highlights the internal elastic lamina, which demonstrates loss and fragmentations. Phagocytosis of elastic fibers is remarkably showed (arrow)