Appendiceal Immunoglobulin G4-Related Disease Mimicking Appendiceal Tumor or Appendicitis: A Case Report

Abstract

Immunoglobulin G4 (IgG4)-related disease is an autoimmune disease that forms tumorous lesions. Several cases involving various organs are reported, however, IgG4-related disease involving appendix has not been reported yet. In this report, we presented a case of IgG4-related disease of appendix, which raised a suspicion of appendiceal tumor or usual appendicitis and, therefore, led to unnecessary surgical resection. IgG4-related disease should be considered in the differential diagnosis for a mass-like swelling of the appendix, in order to avoid unnecessary surgery.

European Guideline on IgG4‐related digestive disease – UEG and SGF evidence‐based recommendations

“…Subsequently, patients received no glucocorticoid or other immune-suppressive medications and had short follow-up, if any. 100,[110][111][112][113][114] IgG4-related disease of the gut, in many cases, was diagnosed postoperatively for presumed tumour, and patients did not receive any specific treatment with less than 6 months of followup. Most patients were treated with surgical or endoscopic resection, whereas a minority received glucocorticoids and/or immunosuppressants.…”

IgG4-Related Appendiceal Disease: A First Case Report Fulfilling All Pathological Diagnostic Criteria and With Concomitant S100-Positive Dendritic/Schwann Cell Hyperplasia

“…In 2016, Kim and his colleagues reported the first case of appendiceal IgG-RD characterized by increased lymphoplasmacytic infiltration with IHC stains confirming significantly increased IgG4 subset. 8 However, the authors stated the absence of more specific and diagnostic histopathologic, such as obliterative phlebitis and storiform fibrosis. 10 Similarly in 2018, Veerankutty et al briefly described an appendiceal lesion that mimicked a mucocel on computed tomography scan, but the histology revealed patchy lymphoplasmacytic infiltration and storiform pattern of fibrosis 9 but lacking obliterative phlebitis.…”

“…1 However, reports on appendiceal involvement are very limited. Currently, there are only 3 cases that describe a mass-forming lesion with increased IgG4 plasma cells in the appendix, [7][8][9] but none of the cases fulfill all 3 histologic criteria. 10 In this report, we present the first case of IgG4-RD in the appendix that satisfies the full spectrum of histologic…”

RE: Appendiceal Immunoglobulin G4-Related Disease Mimicking Appendiceal Tumor or Appendicitis: A Case Report

“…Kim et al ( 1 ) described subserosal inflammatory cell infiltration mostly constituted by plasma cells with immunohistochemistry stains validating significantly increased IgG4 subset. The authors stated the absence of more specific and diagnostic storiform fibrosis or obliterative phlebitis.…”

“…We read with great interest the article by Kim et al ( 1 ), titled “Appendiceal immunoglobulin G4-related disease mimicking appendiceal tumor or appendicitis: a case report,” that described the first report of immunoglobulin G4 (IgG4)-related disease involving appendix. The authors emphasized the significance of recognizing this relatively recent entity in the differential diagnosis for a massforming lesion to avoid unnecessary surgery.…”