Mikulicz's Disease and its Extraglandular Lesions

Mikulicz's disease has been considered a part of primary Sjogren's syndrome since Morgan's 1953 report. Mikulicz's disease is a unique condition involving enlargement of the lacrimal and salivary glands, as is also seen in Sjogren's syndrome; however, Mikulicz's disease is clinically characterized by infrequent autoimmune reactions and responsiveness to glucocorticoid. Fifty years after Morgan's study, the understanding of Mikulicz's disease has changed considerably. We first found elevated levels of serum IgG4 and prominent infiltration by plasmacytes bearing IgG4 in the lacrimal and salivary glands in Mikulicz's disease. These findings do not occur in Sjogren's syndrome. The various extraglandular complications of Mikulicz's disease, including autoimmune pancreatitis, tubulointerstitial nephritis, have gradually been clarified in recent reports. These conditions show similar histopathological findings to Mikulicz's disease, indicating that Mikulicz's disease is a part of a broader entity of systemic IgG4-related disease. We herein describe the clinical features of Mikulicz's disease and its extraglandular lesions.