Immunoglobulin G4-related lymph node disease with an orbital mass mimicking Castleman disease: A case report.

BACKGROUND

Immunoglobulin (Ig) G4-associated diseases are a group of systemic diseases involving multiple organs and are also known as IgG4-associated sclerosing diseases. IgG4-associated lymphadenopathy occurring in the lymph nodes is characterized by a lack of specificity due to its clinicopathological characteristics and must be differentiated from a variety of lesions, such as Castleman disease, lymphatic follicular reactive hyperplasia, and lymphoma.

CASE SUMMARY: A 65-year-old male patient, with Guillain-Barre syndrome for 5 years, presented to our hospital complaining of bilateral orbital mass for 2 years. After hospitalization, the results of the patient's laboratory tests showed that immunoglobulin subgroup IgG4 was 33.90 g/L and IgG was 30.30 g/L, but serum interleukin-6 was normal. The pathological morphology of orbital mass and cervical lymph node were consistent, which showed that a large number of plasma cells and eosinophils were observed in the lymphatic follicles, and the interstitial fibrous tissue was proliferative. Immunohistochemistry showed that CD20 (B cells) (+), CD3 (T cells) (+), CD38 (+), IgG (+), IgG4 positive cells > 100/high powered field, and IgG4/IgG > 40%. Combined with clinical and immunohistochemical results, lymphadenopathy was consistent with Castleman disease-like IgG4-associated sclerosing disease. Prednisone acetate treatment was given at 40 mg/d. After 2 wk, the superficial lymph nodes and orbital masses shrank, and the IgG4 level decreased. As prednisone acetate was regularly used at a reduced dosage, no recurrence of the disease has been observed.

CONCLUSION

This case suggested that it is necessary to proceed cautiously in clinical practice with such patients, and immunoglobulin, complement, interleukin-6, C-reactive protein, and other examinations should be performed to confirm the diagnosis.