Isolated Otologic Involvement of IgG4 Related Disease: A Case Report and Review of Literature.

Immunoglobulin G4 related disease (IgG4-RD) is a systemic autoimmune disease process that classically presents with multi-organ involvement; however isolated involvement of various structures within the body has also been described. Histopathologic examination is considered the gold standard for diagnosis. Glucocorticoids are well established as first-line treatment, but relapses are common, and consultation with rheumatology, immunology, and/or oncology teams is almost always warranted for proper medical management and disease maintenance. Given the relative infancy of IgG4-RD as an accepted diagnosis and the overall rarity of the disease, much still needs to be learned about this variable disease process. We present this case of isolated otologic and lateral skull base involvement of IgG4-RD to contribute to the understanding of this exceedingly rare clinical entity.