Systemic Amyloidosis as a Rare Complication of IgG4 Related Disease: Case Report and Literature Review

Abstract Immunoglobulin 4 Related Disease (IgG4-RD) is immune-mediated fibroinflammatory disease and despite recent advances the immunological process involved in the disease pathogenesis is still unclear. Serum amyloid A (SAA) the precursor protein in AA amyloidosis is induced by inflammatory mediators such as IL-1, IL-6 and TNF cytokines. The treatment of AA amyloidosis is directed by the theoretical cytokine involved in the underlying inflammatory condition. Many inflammatory conditions has already been associated to AA amyloidosis and secondary to IgG4-RD seems to be rare. Here we report the case of a Brazilian patient with IgG4-RD with a fatal evolution of systemic amyloidosis. We also revised the cases already reporte in the literature with IgG4-RD and systemic amyloidosis.