Diagnosis: Lupus Vasculopathy
• A vasculopathy is defined as a noninflammatory lesion initiated by immune complexes and a lesion secondary to acute or chronic thrombosis resulting from several forms of endothelial injury, including antiphospholipid antibodies.
• A vasculitis is characterized by infiltration of the vessel wall (transmural) by leukocytes (mononuclear or polymorphonuclear leukocytes), endothelial damage, segmental or circumferential eosinophilic “fibrinoid” necrosis of the wall with neutrophils, fragmented nuclei, and elastic membrane disruption, features similar to the features seen in small vessel vasculitides.
• In some cases, such as the case presented here, the diagnostic vascular changes are seen only in the tissue submitted for electron microscopy. This situation emphasizes the need to evaluate all tissue sent not only for light microscopy but also for immunofluorescence and electron microscopy so as not to miss diagnostic lesions. Semithin sections from the tissue submitted for electron microscopy should always be evaluated under the light microscope so as not to miss focal lesions like the one shown here.
• Although arteriolar hyalinosis and arteriosclerosis of vessels can significantly compromise the vascular lumen, no immune complex type electron dense deposits would be seen by electron microscopy and immunofluorescence microscopy.
• The presence of a lupus vasculopathy is crucial to document because it portends a very aggressive clinical course and poor prognosis.
