56-Year-Old Man With Rash, Abdominal Pain, and Arthralgias Bettina M. Knoll, MD, PhD, Alfred Valles, MD, Marie C. Hogan, MD, PhD  Mayo Clinic Proceedings  Volume 82, Issue 6, Pages 745-748 (June 2007) DOI: 10.4065/82.6.745 Copyright © 2007 Mayo Foundation for Medical Education and Research Terms and Conditions

FIGURE 1 Palpable purpuric lesions on the lower extremities of a patient presenting with abdominal pain and arthralgias. The lesions were also distributed on the abdomen and buttocks (not shown). Mayo Clinic Proceedings 2007 82, 745-748DOI: (10.4065/82.6.745) Copyright © 2007 Mayo Foundation for Medical Education and Research Terms and Conditions

FIGURE 2 Immunofluorescence microscopy of kidney biopsy specimen showing granular mesangial staining (2-3+) for IgA in glomeruli. In addition, 3 of 12 glomeruli showed involvement by active necrotizing lesions with epithelial reaction and cellular crescent formation (not shown), and electron microscopy showed mild segmental podocyte foot process effacement. Staining for IgM (1+), C3 (2+), κ light chain (2+), and λ light chain (1+) was positive in the same distribution. Staining for fibrinogen (2+) was noted in scattered glomeruli distributed in a mesangial and capillary loop pattern. Mayo Clinic Proceedings 2007 82, 745-748DOI: (10.4065/82.6.745) Copyright © 2007 Mayo Foundation for Medical Education and Research Terms and Conditions