Ocular manifestations of IgG4-related disease in children. More common than anticipated? Review of the literature and case report.

IgG4-related disease (IgG4-RD) is an entity with various clinical manifestations. Histopathologically, it is characterized by lymphoplasmacytic infiltrates enriched in IgG4 (+) plasmacytes and usually fibrosis of the affected tissue. Most of the patients have also increased IgG4 serum levels and they respond to glucocorticosteroids. In children, due to its rare occurrence, IgG4-RD is ill defined. From the published studies, so far, it appears that ocular manifestations are very common in the paediatric population with IgG4-RD. Herein, we describe a new case of a child with IgG4-RD with ocular involvement manifested with orbit and eyelid swelling, successfully treated with steroids. In addition, we review the clinical, laboratory, histopathologic and radiologic characteristics of the published paediatric cases with IgG4-RD and ocular involvement, critically comparing them with the characteristics of the adult population. It seems that ocular manifestations are more frequently observed in children than in adults. Also, the pattern of involvement is different, with extraocular muscles and soft tissues being more commonly affected than the lacrimal glands.