Gallium SPECT/CT in evaluation of IgG4-related disease: A case report and literature review

BACKGROUND

The clinical picture of IgG4-related sclerosing disease (IgG4-RSD) may mimic lymphoma, and should be in the differential diagnosis of patients with this clinical picture.

CASE SUMMARY

A 32-year-old female had recurrent swelling of both eyelids for more than 15 years. Examination revealed elastic, firm, swollen lacrimal glands about 2-3 cm in diameter that was not painful. Head and orbits magnetic resonance imaging (MRI) showed mass lesions over the bilateral lacrimal glands, submandibular glands, and left foramen of ovale. The differential diagnosis included lymphoid tissue, inflammatory masses, and lymphoma. Gallium single-photon emission computed tomography/computed tomography (SPECT/CT) showed uptake in the bilateral lacrimal glands, right parotid and bilateral submandibular glands, bilateral perirenal region, mediastinal, prevertebral, paraaortic, lumbar, bilateral pelvic (including internal iliac chain) lymph nodes, anterior aspect of right 3rd rib, and lateral aspect of left 6th rib. CT showed multiple enlarged lymph nodes in the mediastinum, right pulmonary hilum, prevertebral space of the thoracolumbar spine, retroperitoneal paraaortic area, bilateral parailiac areas, and bilateral perirenal spaces. Antinuclear and anti-SSA/SSB antibodies were negative, and the serum IgG4 level was 740 mg/dL (normal, 8-140 mg/dL). Right parotid gland biopsy showed abundant IgG4-positive plasma cells. Mikulicz disease (IgG4-related sclerosing disease) was diagnosed and she received glucocorticoid treatment. Follow-up CT and MRI showed with resolved eyelid swelling and perirenal mass lesions. Follow-up gallium scan was normal.

CONCLUSION

Gallium SPECT/CT can be a useful tool for initial and follow-up evaluation of IgG4-RSD.

Clinical significance of complement as a biomarker of disease activity in 4 cases of IgG4-related disease with retroperitoneal fibrosis

Hypocomplementaemia is frequently observed in IgG4-related diseases, however the clinical significance is unclear. We describe herein the clinical courses of 4 patients with IgG4-related disease with hypocomplementaemia. Our cases showed autoimmune pancreatitis, retroperitoneal fibrosis, Mikulicz's disease, interstitial lung disease, lymphadenopathy and mesenteric fibrosis around the aorta. A decrease in serum complement preceded deterioration of the disease and clinical improvement was observed in accordance with normalisation of serum complement. These clinical courses suggest that serum complement is a biomarker of the disease activity.

IgG4-related Mikulicz's disease: ultrasonography of the salivary and lacrimal glands for monitoring the efficacy of corticosteroid therapy

OBJECTIVES

IgG4-related Mikulicz's disease (IgG4-MD) has been recently established as a subtype of IgG4-related diseases involving the salivary and lacrimal glands, and the diseased glands are characteristically and highly responsive to corticosteroid therapy. We retrospectively evaluated ultrasonography (US) of the salivary and lacrimal glands for monitoring the efficacy of corticosteroid treatment in patients with IgG4-MD.

METHODS

US features of the salivary and lacrimal glands were assessed and compared with the serum IgG4 levels in 8 patients with IgG4-MD before and at various stages after initiation of oral corticosteroids.

RESULTS

US features of the lacrimal and salivary glands of patients with IgG4-MD were characterised by multiple hypoechoic areas in enlarged glands. The submandibular glands were most frequently involved by the disease, and bilateral glands of the same type were similarly affected exhibiting the same hypoechoic pattern. Alleviations of abnormal gland architecture and size in response to corticosteroid therapy were effectively detected with US. The US findings of the involved glands were proportional to the serum IgG4 level before and during the corticosteroid therapy.

CONCLUSIONS

US helps monitor the efficacy of corticosteroid treatment in patients with IgG4-MD.

[Divergence between measured values of total IgG and subclass IgGs (sum of IgG1-IgG4) in IgG4-related disease]

In systemic IgG4-related disease, an elevation of the serum IgG4 level(IgG4: 135 mg/dl or higher) and IgG4-positive plasma cell infiltration occurs. Since the total IgG and sum of subclasses, IgG1 through IgG4, were markedly different in a patient suspected of having Mikuliez's disease, we investigated the relationship between total IgG and sum of IgG subclasses. The subjects were healthy individuals, and low IgG4, high IgG4, hyper-gamma globulinemia and hypo-y globulinemia groups. Total IgG was measured using 'N-assay TIA IgG-SH' (Nittobo) and Hitachi 7700, and IgG subclasses were measured using BS-NIA reagent (Binding Site) and BN II (Siemens). Designation of total IgG and the sum of IgG subclasses was established in the healthy control subjects. However the total IgG level and sum of IgG1-4 levels were different when the balance among the IgG subclasses was lost. In case such as :1) the IgG4 level was high and 2) IgG1-type M protein was present. These results indicate that the reevaluation of measured data is necessary when the IgG4 concentration is high and the difference between total IgG concentration and the sum of IgG subclasses is large.

Serial changes of elevated serum IgG4 levels in IgG4-related systemic disease

OBJECTIVE

Autoimmune pancreatitis (AIP) and Mikulicz's disease have recently been recognized as pancreatic or salivary gland lesions of IgG4-related systemic disease. These are frequently associated with elevated serum IgG4 levels. This study aimed to clarify clinical implications of serial changes of elevated serum IgG4 levels in IgG4-related systemic diseases.

METHODS

Serial changes of elevated serum IgG4 levels were examined in patients with IgG4-related systemic diseases. Patients Serial changes of elevated serum IgG4 levels were examined in 44 patients: AIP (n=24), Mikulicz's disease (n=8), pancreatic cancer (n=5), bile duct cancer (n=1), sclerosing cholangitis (n=1), hypereosinophilic syndrome (n=1), chronic thyroiditis (n=1), hypophysitis (n=1), idiopathic pancreatitis (n=1), and Behcet's disease (n=1).

RESULTS

The serum IgG4 levels decreased in all patients with AIP and Mikulicz's disease after steroid therapy. The serum IgG4 levels were normalized in 46% of AIP patients and 38% of Mikulicz's disease patients. The serum IgG4 levels were not normalized at remission in 3 of 4 relapsed AIP patients, and re-elevation of serum IgG4 levels was detected in all relapsed patients. Elevated serum IgG4 levels decreased in 3 patients with pancreatic cancer after resection or chemotherapy, and decreased in patients with hypereosinophilic syndrome, sclerosing cholangitis, and hypophysitis after steroid therapy.

CONCLUSION

Measurement of serial serum IgG4 levels is useful to determine the disease activity of IgG4-related systemic diseases.

Proteomics analysis in 28 patients with systemic IgG4-related plasmacytic syndrome

It is considered that autoimmune pancreatitis (AIP), Mikulicz's disease (MD) and IgG4-related tubulointerstitial nephritis (TIN) comprise systemic IgG4-related plasmacytic syndrome (SIPS), of which the origin remains unknown. We analyzed these patients with focus on serological aspects to invest whether there are autoantigens in SIPS. We evaluated 28 patients with SIPS who presented at Sapporo Medical University Hospital and the collaborated institutions. They were mainly middle-aged (eight male), and consisted of 26 patients with MD and two patients with AIP. The three among 26 patients diagnosed with MD were complicated to AIP, and another three patients had IgG4-related TIN. As a control, healthy volunteers and the patients with Sjögren's syndrome were examined. At first, we measured the levels of serum complements and circulating immune complexes in these patients. Next, immune complexes were collected from the serum of patients and healthy controls by immunoprecipitation. They were divided into immunoglobulin and the antigens by glycine-HCl solution. The divided samples including the antigens were analyzed by surface-enhanced laser desorption/ionization-time of flight-mass spectrometry (SELDI-TOF-MS). Nine patients had hypocomplementemia and 15 had elevated levels of circulating immune complexes in the group of SIPS. In the groups of healthy volunteers and SS, all showed that the levels of serum complements and circulating immune complexes were normal. SELDI-TOF-MS detected a 13.1-kDa protein from all samples of SIPS, and not in normal control and SS. It is possible that the 13.1-kDa protein is one of the autoantigens of SIPS.

Elevated IgG4 concentrations in serum of patients with Mikulicz's disease

Mikulicz's disease has recently been included within primary Sjögren's syndrome. It is a unique condition involving enlargement of the lacrimal and salivary glands, characterized by few autoimmune reactions. It is responsive to glucocorticoid treatment. Analysis of IgG fractions was performed in patients with Mikulicz's disease in order to determine the differences between Mikulicz's disease and Sjögren's syndrome. The study showed that serum IgG4 concentrations are elevated in patients with Mikulicz's disease, but not in those with Sjögren's syndrome.

Aphthous ulceration: the antinuclear factor

The incidence of the antinuclear factor in serum of patients with Mikulicz's recurrent oral aphthae (MROA) was compared with that in control serum. The absence of any difference between the two groups suggests that MROA is not an autoimmune disease arising from a central immunologic fault, but could be a local immune response against an antigenically altered mucosa.