Table 2. Teaching points.

IgG4-RD is an immune-mediated systemic inflammatory condition that can affect the kidneys, nervous system, and many other organs.

IgG4-RD is histopathologically characterized by storiform fibrosis and IgG4-positive plasma cell infiltration of affected tissues, and is often associated with elevated serum IgG4 concentrations.

IgG4-RD can be treated with glucocorticoids as well as other immunomodulatory or immunosuppressive agents.

There is overlap in the presentations of IgG4-RD and ANCA-associated vasculitis.

Consider IgG4-RD in the differential diagnosis in patients with peripheral neuropathy and evidence of systemic inflammatory disease.