Successful treatment with rituximab of IgG4-related disease coexisting with adult-onset asthma and periocular xanthogranuloma

Immunoglobulin G4-related disease (IgG4RD) is a systemic fibro-inflammatory disease of unknown aetiology, which is characterized by tumefactive lymphoplasmatocytic infiltrative lesions, with a predominance of IgG4 positive plasma cells, fibrosis and obliterative phlebitis. Adult-onset asthma and periocular xanthogranuloma (AAPOX) is a rare disease of unknown aetiology characterized by violaceous or yellow cutaneous papules and nodules usually accompanied with adult-onset asthma. We report a case of IgG4RD associated with AAPOX. We also conducted a literature search with keywords including IgG4RD and AAPOX. A 36-year-old woman presented with bilateral exophthalmos and periorbital oedema. Keratoconjunctivitis sicca, painless left parotid gland and submandibular left lymph node enlargement were also noted. Two and half years ago biopsy of yellow plaques of her right lower eyelid confirmed periorbital xanthogranuloma. She underwent parotid gland biopsy which showed IgG4RD. She was treated with steroids and two cycles of rituximab with complete remission. The literature review revealed 8 articles describing 14 cases with IgG4RD and AAPOX, 9 men and 5 women (ratio M:F = 1.8:1) were affected. The age at diagnosis was greater in men compared to women. In the majority of patients, ophthalmic presentation included bilateral upper and lower eyelid swelling while systemic features were asthma, lacrimal and parotid involvement, lymphadenopathy, sclerosing pancreatitis and sclerosing cholangitis. Prednisone and rituximab were effective treatments. It has to be clarified whether the association between IgG4RD and AAPOX represents shared pathophysiology, a common underlying cause or coincidence. Rituximab added to steroids resulted in complete remission of the two entities.