case_images: PMC8405098_01
case_images: Clinical presentation: (A) multiple linear and serpiginous purpura on the abdomen, (B) back, (C) left thigh.
case_images: CCID-14-1057-g0001.jpg
case_images: PMC8405098_01_CCID-14-1057-g0001.jpg
case_images: f0001
case_images: On examination, there were multiple linear and serpiginous non-blanchable erythematous patches on abdomen and both thighs (Figure 1A-C).
case_images: Histopathological and direct immunofluorescence findings: (A) Superficial perivascular infiltration with lymphocytes, neutrophils, nuclear dusts, and extravasated red blood cells, with superficial vascular lumen occlusions. (B) Positive Periodic acid-Schiff (PAS) staining in vessel lumens and vessel walls. (C) Positive IgM staining in vessel lumens and vessel walls. (D) Granular deposition of C3 in superficial vascular walls.
case_images: CCID-14-1057-g0002.jpg
case_images: PMC8405098_01_CCID-14-1057-g0002.jpg
case_images: f0002
case_images: A skin biopsy of the lesion on his abdomen revealed dense superficial perivascular infiltration with lymphocytes, neutrophils, nuclear dusts and extravasated red blood cells, along with some superficial vascular lumen occlusions (Figure 2A). Further staining with Periodic acid-Schiff (PAS) showed eosinophilic homogenous materials in vascular lumens and vascular walls (Figure 2B), which were negative for Congo red. Immunohistochemistry also highlighted deposition in the vessel lumens and vessel walls with IgM (Figure 2C), but not with IgG, IgA and IgD. With C3, both homogenous deposition in the vessel walls and granular deposition on the perivascular areas were detected (Figure 2D).
case_images: Resolution of lesions on the abdomen.
case_images: CCID-14-1057-g0003.jpg
case_images: PMC8405098_01_CCID-14-1057-g0003.jpg
case_images: f0003