Corynebacterium kroppenstedtii in granulomatous mastitis: Analysis of formalin-fixed, paraffin-embedded biopsy specimens by immunostaining using low-specificity bacterial antisera and real-time polymerase chain reaction

Mari Fujii, Yasuyoshi Mizutani, Takahiko Sakuma, Kouichiro Tagami, Kiichiro Okamoto, Yasushi Kuno, Michihiko Harada, Koichi Kubouchi, Yutaka Tsutsumi

研究成果: Article

6 引用 (Scopus)


Granulomatous mastitis (GM) is a rare inflammatory disease of the post-lactation breast, clinically mimicking breast cancer. GM is microscopically characterized by formation of epithelioid granulomas and abscess (suppurative granulomas) with lipid droplet-centered inflammation. Corynebacterium kroppenstedtii (Ck) is known as a causative bacterium of GM, and identification of Ck infection within the lesion should thus be essential for confirming the diagnosis. In the present study, we analyzed formalin-fixed, paraffin-embedded (FFPE) biopsy specimens of a total of 18 GM lesions with immunostaining and real-time PCR for Ck genome. Widely cross-reactive rabbit antisera against Bacillus Calmette-Guerin (BCG), Bacillus cereus, Treponema pallidum and Escherichia coli were chosen. With real-time PCR, Ck genome was demonstrated in 7 of 18 GM lesions. Immunohistochemically, the low-specificity antisera reacted with the cytoplasm of phagocytes and/or granuloma-engulfed lipid droplets in 12 of 18 GM lesions. Antigenic positivity was observed in the following order: BCG > B. cereus > T. pallidum > E. coli. Real-time PCR using DNA extracted from FFPE sections was useful but not consistent for identifying the Ck genome in GM, while immunostaining using cross-reactive antisera against four kinds of bacteria was not Ck-specific but was applicable to visualizing bacterial infection within the GM lesions.

ジャーナルPathology International
出版物ステータスPublished - 07-2018


All Science Journal Classification (ASJC) codes

  • Pathology and Forensic Medicine