Cutaneous manifestations of IgG4-related disease (RD): A systematic review

Background: IgG4-related disease (RD) is a recently described fibroinflammatory condition with both cutaneous and systemic manifestations. To our knowledge, the cutaneous manifestations have not been well characterized or systematically investigated to date in the literature. Objective: We sought to describe the cutaneous manifestations of IgG4-RD to guide clinical practice, aid in the diagnosis of IgG4-RD, and contribute to the creation of robust cutaneous diagnostic criteria. Methods: A systematic search of peer-reviewed publications pertaining to cutaneous manifestations of IgG4-RD yielded 56 cases from 32 case reports and series. The clinical findings among the diagnostic categories were compared. Results: Forty cases of IgG4-RD with cutaneous disease were identified. Cutaneous head and neck involvement was significantly associated with a diagnosis of IgG4-RD (P = .02). Macules and bullae were not described in any of the included cases. Among cases of systemic IgG4-RD, cutaneous head and neck involvement was most common and statistically significantly associated with the diagnosis of IgG4-RD(P = .001). Limitations: These findings are limited by reporting and publication bias of particular cases and by small sample size. Conclusions: Papules, plaques, and nodules of the head and neck appear to characterize patients with cutaneous IgG4-RD, which nevertheless usually presents with systemic manifestations.