IgG4-related Disease from Head to Toe

Abstract

■ Identify the most commonly affected organs in IgG4-related disease. ■ Describe characteristic imaging findings of pancreatic and extrapancreatic IgG4-related disease. ■ Discuss the differential diagnosis in each affected organ.

Sonographic findings of IgG4‐related disease of the salivary glands: Case report and review of the literature

“…Salivary gland involvement in IgG4‐related disease has been previously erroneously characterized as subcategories of Sjogren's syndrome with involvement of the lacrimal, parotid, and submandibular glands being characterized as “Mikulicz disease” and isolated chronic involvement of the submandibular gland being characterized as “Kuttner's tumor.” Our literature review suggests that hypoechoic lesions involving preferentially the submandibular glands (with common sparing of the parotid glands) are sonographic features consistent with IgG4‐related disease involving the salivary glands. These sonographic features show significant overlap with those found in patients with Sjogren's syndrome, in whom multiple hypoechoic lesions and heterogeneous echotexture are often seen in salivary glands with earlier and more pronounced involvement of the submandibular glands compared with the parotid glands .…”

Mesenteric tumour deposits arising from small‐intestine neuroendocrine tumours are frequently associated with fibrosis and IgG4‐expressing plasma cells

“…When present, they are usually larger than primary tumours. Sometimes MTDs may be the only finding on imaging studies, and distinction between other processes such as lymphoma and other mesenteric diseases can be difficult by imaging alone …”

“…Sometimes MTDs may be the only finding on imaging studies, and distinction between other processes such as lymphoma and other mesenteric diseases can be difficult by imaging alone. 7,10 IgG4-related disease is a fibroinflammatory tumefactive process characterised by a dense lymphoplasmacytic infiltrate enriched with IgG4-positive PCs, storiform fibrosis, and frequent elevations of serum IgG4. 11 It was first recognised in patients with autoimmune pancreatitis who manifested with extrapancreatic symptoms.…”

“…In addition, MTDs are frequently associated with dense fibrosis, which can lead to entrapment of adjacent large mesenteric vessels and nerves. Because of this dense fibrotic response to tumour, MTDs can radiographically simulate IgG4‐related sclerosing mesenteritis, complicating diagnosis by imaging and necessitating tissue diagnosis …”

“…Because of this dense fibrotic response to tumour, MTDs can radiographically simulate IgG4-related sclerosing mesenteritis, complicating diagnosis by imaging and necessitating tissue diagnosis. 7 IgG4-related sclerosing mesenteritis is characterised by fibrosis, lymphoplasmacytic inflammation, and obliterative thrombophlebitis with prominent IgG4positive plasma cells (PCs). 8 Microscopically, the sclerosing fibrotic stromal response associated with MTDs is often accompanied by similar adjacent foci of lymphoplasmacytic inflammation.…”