Mikulicz’s disease (MD) is thought to be a manifestation of Sjögren’s syndrome (SS). The patients presented here were originally thought to have MD, SS, or Kuttner tumour. However, the diagnostic criteria were not satisfied. In addition, two of these patients showed a unilateral submandibular gland tumour mass, which was excised. It is difficult to obtain a needle biopsy from a submandibular tumour mass, in contrast to tumour masses in other organs. In addition, a malignant disease cannot be ruled out because the mass is unilateral, often leaving no choice other than excision. IgG4 related sclerosing disease occurs relatively often among cases of submandibular gland excision and suspected cases of SS (wherein the diagnostic criteria are not satisfied).18–20
If a high serum IgG4 value is observed, it is possible to reduce the tumour mass without performing a resection through the administration of steroids. The serum IgG4 value should be measured in patients with lesions such as fibrosis in an organ, and the patient should be managed in close cooperation with each department as well as cooperation between clinics and hospitals.
The swollen salivary glands disappeared and the serum IgG and IgG4 values decreased dramatically following steroid treatment. These cases of IgG4 related sclerosing disease or hyper-IgG4 disease21
appear to belong to the category of either multifocal fibrosclerosis, systemic idiopathic fibrosis, or fibrotic overlap syndrome.22–24
No consensus has been reached regarding the definition of IgG4 related sclerosing disease. Recently, Masaki et al
proposed a new clinical entity, IgG4 positive multiorgan lymphoproliferative syndrome (MOLPS), based on the clinical features and good response to steroids. Their preliminary diagnostic criteria include increased serum values of IgG4 (>135 mg/dl) and infiltration of IgG4 (+) plasma cells in the tissue (IgG4+/IgG+ plasma cells >50%) with fibrosis or sclerosis.25
The current cases may represent a new category of Japanese patients with IgG4 related sclerosing disease complicated by fibrotic changes in the organs. This may be a variation of IgG4 related sclerosing disease known as hyper-IgG4 disease, or IgG4 positive MOLPS. Larger studies are needed to elucidate the exact mechanism and clinical characteristics of this disorder.
In a case of chronic sclerosing sialadenitis with a high IgG value:
- it would be prudent to measure blood IgG4 value
- if the value is elevated, careful observation needs to exercised for the development of idiopathic retroperitoneal fibrosis, and/or fibrotic changes in the organs
- a strict follow-up is recommended in such cases.