IgG4-related skin disease

IgG4-related skin disease is the recommended name for skin manifestations in IgG4-related disease (IgG4-RD). Multiple different skin manifestations have been described.

Classification
Although a clear understanding of the various skin lesions in IgG4-related disease is a work in progress, skin lesions have been classified into subtypes based on documented cases:
 * Angiolymphoid hyperplasia with eosinophilia (or lesions that mimic it) and cutaneous pseudolymphoma
 * Cutaneous plasmacytosis
 * Eyelid swelling (as part of Mikulicz's disease)
 * Psoriasis-like eruptions
 * Unspecified maculopapular or erythematous eruptions
 * Hypergammaglobulinemic purpura and urticarial vasculitis
 * Impaired blood supply to fingers or toes, leading to Raynaud's phenomenon or gangrene

In addition, Wells syndrome has also been reported in a case of IgG4-related disease.

Note
Note :