Microvasculitis in sural nerve

Serial skip paraffin sections of a microvessel above (upper panels), at (middle panels), and below (lower panels) the region of microvasculitis in the sural nerve of a patient with lumbosacral radiculoplexus neuropathy. The sections in the left column are stained with hematoxylin and eosin; the sections in the middle column are reacted to anti-human smooth muscle actin (Dako, Carpenteria, California); and the sections in the right column are reacted with leukocyte common antigen (CD 45). The smooth muscle of the tunica media in the region of the microvasculitis (middle panels) are separated by mononuclear cells, fragmented, and decreased in amount. The changes are those of a focal microvasculitis. These changes are seen in both the diabetic and nondiabetic conditions. (Dyck PJ, Windebank AJ. Diabetic and nondiabetic lumbosacral radiculoplexus neuropathies: new insights into pathophysiology and treatment. Muscle Nerve 2002;25:477-91. Reprinted with permission of John Wiley & Sons, Inc.)