Periductal Mastitis: An Inflammatory Disease Related to Bacterial Infection and Consequent Immune Responses?

Abstract

Periductal mastitis (PDM) is a prolonged inflammatory disease, but the cause of PDM is poorly understood. In the present case control study, 87 PDM and 87 healthy controls were enrolled and the results were evaluated to identify the significant risk factors for PDM. To investigate the roles of bacterial infection and critical cytokines expression, 16S rRNA gene sequencing and bacterial culturing were conducted. We also measured the levels of interferon-γ, interleukin-12A, and interleukin-17A by semiquantitative immunohistochemistry method. In a multivariable logistic regression model, we identified overweight/obesity and late onset of menarche as independent risk factors for PDM. In contrast, age of first birth >27 years had a protective effect. With 16S rRNA gene sequencing, we confirmed bacterial infections were found in all PDM patients, but none of the control patients was positive on the gene expression of 16S rRNA. Our results also demonstrated significant increases of the IFN-γ and IL-12A expression in PDM, but there was no difference in IL-17A expression in these two groups. Taken together, this study suggests that reproductive factors and overweight/obesity are possible predisposing risk factors for PDM. Bacterial infection and the increased expression of some proinflammatory cytokines are associated with the pathogenesis of this disease.

Mammary duct ectasia in adult females; risk factors for the disease, a case control study

“…Some studies implicate age as one of the risk factors for the development of many benign breast disorders, the age was not a risk factor in our study, and the correlation was not significant when compared to the controls (P value 0.324). Obesity also have been implicated by some authors to have a possible association, although in this study this correlation was not present (P value 0.831) [ 6 , 12 ].…”

“…The tissue examination showed various degrees of inflammation, infiltration with chronic inflammatory cells particularly plasma cells, and foam cell formation, breast duct dilatation, periductal fibrosis, intraepithelial histiocytes, calcifications in duct lumen or duct wall, and abscess formation [ 3 , 4 , 12 ].…”

Risk of breast cancer in women with non-lactational mastitis

“…Our results showed that the risk of breast cancer in women increased significantly as the occurrence of non-lactational mastitis increased. Non-lactational mastitis is known to be related to chronic inflammation secondary to infection-induced cytokines 30 , as well as inflammatory, infectious, hormonal and autoimmunity factors 31,32 . Reportedly, the presence of exogenous and endogenous pathogen-associated molecular patterns (PAMPs) (bacteria, viruses and fungi, as well as endogenous molecules released from injured or dying cells) can cause the activation of inflammatory pathways 33 .…”

Idiopathic Granulomatous Mastitis: Manifestations at Multimodality Imaging and Pitfalls

“…In comparison, IGM usually involves a tender mass and is typically peripheral and unilateral. Other common clinical findings include a nonbloody nipple discharge and nipple retraction (61), which are uncommon with IGM. Mammary duct ectasia may be more confidently diagnosed when similar imaging features are seen bilaterally.…”