Immunocytochemical Observations in Periarteritis Nodosa

Abstract

A case of polyarteritis supplied an opportunity for immunocytochemical investigations of various tissues and cells in one of the so-called collagen diseases. Such studies are few in number, especially in periarteritis nodosa, and may serve as a helpful tool in clarifying the nature of one or the other form of vascular disease. The morphological features of the case were essentially those of "classical periarteritis nodosa." Necrotizing arteritis was encountered in many organs. The kidneys displayed focal necrotizing glomerulitis in addition to arterial lesions. Gamma globulin, fibrinogen and albumin were demonstrated in acute vascular and renal lesions. These findings were interpreted as inhibition of the damaged tissues with plasma proteins. Immunohistochemical findings in the spleen and lymph nodes and some serological reactions suggested an immunological component. Gamma globulin was found in cells of the spleen, lymph nodes and kidneys. Additional cells in the spleen, with the morphologic characteristics of plasma cells contained macroglobulin (19S). Positive staining of these cells with fluoresceinated aggregated human gamma globulin suggests that they contain rheumatoid factor. This finds support in a positive latex fixation test in the serum of the patient. It did not react with vascular wall antigens; thus it is unlikely that an auto-specific antigen-antibody reaction caused the arteritic lesions. Of special interest is the demonstration of macroglobulin and rheumatoid factor, both in serum and tissue of the patient. This phenomenon suggests an abnormal immune response, common to various disease states known under the name of collagen diseases.