Etiology of granulomatous lobular mastitis based on metagenomic next-generation sequencing

Clinical Characteristics of Non-Puerperal Mastitis: A Retrospective Analysis of 724 Patients

Objective

The aim of this study is to retrospectively analyze the clinical characteristics of non-puerperal mastitis.

Methods

A retrospective study was undertaken to investigate 724 cases of non-puerperal mastitis in patients hospitalized from April 2004 to December 2021 at the Mammary Gland Department of Shuguang Hospital, which is affiliated with Shanghai University of Traditional Chinese Medicine. Employing statistical methodologies including mean ± standard deviation, median, and one-sample t-test, the study sought to analyze and delineate factors associated with morbidity, such as age, childbirth, lactation, and body mass index (BMI).

Results

The average age of the 724 patients was 33.4 ± 5.5 years. Among them 54.94% were aged 30-39 years, 65.16% were within five years after delivery, and 62.56% were breastfeeding for less than 6 months. The BMI of patients aged 30-39 years was higher than that of the general Chinese population (P < 0.05). There was no significant correlation between smoking, oral contraceptives, trauma, and the incidence of the disease in this group.

Conclusion

Non-puerperal mastitis is more prevalent among women of childbearing age, specifically those aged 30-39 years, who breastfed for less than 6 months within the first five years after childbirth. In this age group, higher BMI is linked to increased morbidity.

Optimal Timing for Corticosteroid Therapy in Idiopathic Granulomatous Mastitis: A Retrospective Analysis Highlighting Early Intervention Efficacy

BACKGROUND

Idiopathic granulomatous mastitis (IGM) is a chronic breast condition known for its aggressive nature and tendency for persistence and recurrence. Steroids are commonly used as the first-line treatment for IGM, but issues such as the optimal timing, and duration of treatment remain debated.

METHODS

We retrospectively analyzed 343 IGM cases treated at the Third People's Hospital of Chengdu from September 2012 to September 2023. Based on inclusion and exclusion criteria, a total of 188 patients were included in the study. Patients were categorized into lump (78 cases), abscess (81 cases), and sinus tract stages (29 cases) according to their initial diagnosis upon admission. Prednisolone was initiated at 0.75 mg/kg/day, and after effective treatment, the dosage was adjusted by 5-10 mg weekly, followed by a maintenance dose of 2.5-5 mg/day. Clinical characteristics, treatment responses, adverse effects, recurrence rates, and follow-up data were assessed.

RESULTS

The median duration of prednisone treatment in our study was 87 days (range, 21-281 days). Positive response rates to prednisolone were 78.2% in the lump stage, 60.5% in the abscess stage, and 62.1% in the sinus tract stage. Continuing low-dose prednisone for 3 months post-effective treatment reduced recurrence rates and side effect risks. Weight gain was the most common side effect (39.36%).

CONCLUSION

Early steroid therapy, especially in the lump stage, demonstrated superior efficacy. Following a regimen of starting with a full dose, tapering slowly, and maintaining a low dose for around 3 months steroids treatment is recommended to minimize recurrence rate and adverse effects.

Clinical characteristics of patients with granulomatous lobular mastitis associated with Corynebacterium parakroppenstedtii infection and drug sensitivity analysis of the isolated strains

BACKGROUND

It is presently considered that Corynebacterium especially Corynebacterium kroppenstedtii (CK) infection, is one of the important causes of granulomatous lobular mastitis (GLM). However, the pathogen of mastitis in the past two years has been identified as a newly discovered Corynebacterium. But it is unclear whether the pathogen associated with the occurrence of GLM is also this bacterium.

METHODS

GLM female patients with positive bacterial culture in pus specimens from February 2023 to February 2024 who were identified as CK infection by mass spectrometer were selected as the research objects in this study, and the clinical isolates were identified by 16S rDNA sequencing technology to identify the specific pathogen of GLM-related bacterial infection. Subsequently, the clinical characteristics of the patients were compared with those of GLM patients without bacterial infection during the same period, to explore the effect of this particular type of Corynebacterium infection on disease development in GLM patients. Finally, we tested the minimum inhibitory concentration (MIC) values of antibiotics when inhibiting these separation strains in vitro through the E-Test experiment, to evaluate their medicine sensitivity.

RESULTS

A total of 31 GLM patients initially diagnosed with Corynebacterium kroppenstedtii (CK) infection via MALDI-TOF MS were enrolled in the study. However, subsequent 16S rDNA sequencing revealed that 28 isolates (90.32%) were actually identified as the newly recognized Corynebacterium parakroppenstedtii (CPK). This discovery challenges the conventional belief that CK is the primary pathogen of GLM, suggesting instead that CPK is the predominant pathogen associated with GLM bacterial infections. Comparative analysis of the clinical characteristics between the two groups revealed a significantly higher recurrence rate among CPK-infected GLM patients compared to those without CPK infection, along with elevated prolactin levels (P < 0.05). The sensitivity test results indicated high sensitivity of the isolates to vancomycin, linezolid, and rifampicin.

CONCLUSION

In conclusion, this study highlights that Corynebacterium kroppenstedtii strains isolated from GLM specimens were Corynebacterium parakroppenstedtii, serving as the primary pathogen closely linked to GLM's occurrence. CPK infection significantly increases the risk of recurrence in GLM patients, with elevated prolactin levels potentially playing a pivotal role in this process. In clinical antimicrobial treatment, antimicrobials other than penicillin and ciprofloxacin may be empirically administered when sensitivity test results are inconclusive.

Ductal lavage followed by observation versus oral corticosteroids in idiopathic granulomatous mastitis: A randomized trial

Oral corticosteroids represents the most prevalent treatment for idiopathic granulomatous mastitis. Ductal lavage with triamcinolone acetonide and antibiotics followed by observation (DL-OBS) has emerged as a novel strategy, but a comparison of them remains lacking. Here in this multicenter, open-label, non-inferiority, randomized trial (ClinicalTrials.gov identifier: NCT03724903), we assigned 140 patients to oral corticosteroids (N = 71) and DL-OBS (N = 69), stratified by baseline M-score. The primary outcome is complete Clinical Response rate at 1 year. The non-inferiority margin is -15%. The primary outcome is 85.5% in DL-OBS and 87.3% in oral corticosteroids (difference: -1.8%; 95%CI, 13.2 to 9.5; Pnon-inferiority = .01) in intention-to-treat population, and 92.6% vs 98.2% (difference -5.6%; 95%CI -13.4 to 2.2; Pnon-inferiority = .01) in per-protocol population, respectively. The most common (>15%) adverse events were Cushingoid, epigastric pain and arthralgia in oral corticosteroids, and irregular menstruation in DL-OBS, respectively. Here, we report that DL-OBS shows similar efficacy to oral corticosteroids but with better safety profile.

Corynebacterium parakroppenstedtii secretes a novel glycolipid to promote the development of granulomatous lobular mastitis

Granulomatous lobular mastitis (GLM) is a chronic idiopathic granulomatous mastitis of the mammary gland characterized by significant pain and a high propensity for recurrence, the incidence rate has gradually increased, and has become a serious breast disease that should not be ignored. GLM is highly suspected relative to microbial infections, especially those of Corynebacterium species; however, the mechanisms involved are unclear, and prevention and treatment are difficult. In this study, we demonstrated the pathogenicity of Corynebacterium parakroppenstedtii in GLM using Koch's postulates. Based on the drug sensitization results of C. parakroppenstedtii, and utilizing a retrospective study in conjunction with a comprehensive literature review, we suggested an efficacious, targeted antibiotic treatment strategy for GLM. Subsequently, we identified the pathogenic factor as a new type of glycolipid (named corynekropbactins) secreted by C. parakroppenstedtii. Corynekropbactins may chelate iron, cause the death of mammary cells and other mammary -gland-colonizing bacteria, and increase the levels of inflammatory cytokines. We further analyzed the prevalence of C. parakroppenstedtii infection in patients with GLM. Finally, we suggested that the lipophilicity of C. parakroppenstedtii may be associated with its infection route and proposed a possible model for the development of GLM. This research holds significant implications for the clinical diagnosis and therapeutic management of GLM, offering new insights into targeted treatment approaches.

Microbiome-Stealth Regulator of Breast Homeostasis and Cancer Metastasis

Cumulative evidence attests to the essential roles of commensal microbes in the physiology of hosts. Although the microbiome has been a major research subject since the time of Luis Pasteur and William Russell over 140 years ago, recent findings that certain intracellular bacteria contribute to the pathophysiology of healthy vs. diseased tissues have brought the field of the microbiome to a new era of investigation. Particularly, in the field of breast cancer research, breast-tumor-resident bacteria are now deemed to be essential players in tumor initiation and progression. This is a resurrection of Russel's bacterial cause of cancer theory, which was in fact abandoned over 100 years ago. This review will introduce some of the recent findings that exemplify the roles of breast-tumor-resident microbes in breast carcinogenesis and metastasis and provide mechanistic explanations for these phenomena. Such information would be able to justify the utility of breast-tumor-resident microbes as biomarkers for disease progression and therapeutic targets.

Novel insights: crosstalk with non-puerperal mastitis and immunity

The two primary types of non-puerperal mastitis (NPM) are granulomatous lobular mastitis (GLM) and plasma cell mastitis (PCM). Existing research indicates that immune inflammatory response is considered to be the core of the pathogenesis of GLM and PCM, and both innate and adaptive immune responses play an important role in the pathophysiology of PCM and GLM. However, the regulatory balance between various immune cells in these diseases is still unclear. Consequently, we present a comprehensive summary of the immune-related variables and recent advances in GLM and PCM.

Granulomatous Mastitis: An Initial Presentation of Undiagnosed Prolactinoma

Granulomatous lobular mastitis (GLM) is a rare, benign inflammatory disease of the breast that shares some physical diagnostic features with breast cancer. GLM has been rarely reported to be associated with prolactinoma. In this report, we present a case of undiagnosed prolactinoma in a 37-year-old woman with its initial presentation as GLM. We discuss the underlying pathophysiologic mechanisms for the development of GLM and the potential immunomodulatory role of prolactin in the development of GLM. We also highlight the need to assess for possible prolactinoma in GLM, which might go undiagnosed as in the case of our patient who did not seek medical attention for her amenorrhea, which is likely due to hyperprolactinemia that might also have other clinical implications on cardiovascular and bone health due to consequent estrogen deficiency.

Periductal Mastitis, a Disease with Distinct Clinicopathological Features from Granulomatous Lobular Mastitis

Purpose

Periductal mastitis (PDM) is a chronic inflammatory lesion of the breast with an unknown etiology, and it is difficult for clinicians to differentiate it from granulomatous lobular mastitis (GLM), although they have different treatment strategies and prognosis. This study aimed to investigate the differences in their clinicopathologic features to inform treatment strategies.

Patients and Methods

Between 2011 and 2020, 121 patients diagnosed with PDM and 57 patients with GLM were retrospective analysis. Patient data were extracted on demographics, clinical presentation, pathologic characteristics, treatments and clinical response. Histopathological evaluations were performed on core needle biopsy specimens. Immunohistochemical stains using antibodies against CD3, CD4, CD8, CD20, and CD138 was performed to define immune cell infiltration.

Results

PDM patients had a higher median age compared to GLM patients (38 vs 32, p<0.001). PDM was primarily located in the areolar area, while GLM predominantly affected the peripheral quadrant of the breast (56.20% vs 75.44%, p<0.001). Histopathologically, more ductal dilatation (90.08% vs 3.51%, p<0.001), ductal wall thickening (47.93% vs 1.75%, p<0.001), and ductal rupture (44.63% vs 5.26%, p<0.001) were observed in PDM. GLM presented with significantly more granuloma (94.74% vs 10.74%, p<0.001), microabscess (68.42% vs 28.93%, p<0.001), and lipid vacuole (40.35% vs 8.26%, p<0.001) formation than PDM. Immunohistochemical analysis revealed a significant presence of CD20+ B lymphocytes in PDM and a higher prevalence of CD8+ T lymphocytes in GLM, indicating differing immune responses. Treatment outcomes varied, with PDM patients responding well to surgery and anti-mycobacterial therapy, while GLM patients showed favorable responses to steroid therapy.

Conclusion

PDM is a specific entity with a similar clinical presentation but distinct histopathological features and immune profiles to GLM. Further research is needed to elucidate the pathogenesis and optimize therapeutic approaches for these breast inflammatory conditions.

Cystic neutrophilic granulomatous mastitis: sensitivity and specificity of 16s rRNA and Sanger sequencing for Corynebacterium spp

AIMS

Cystic neutrophilic granulomatous mastitis (CNGM) is a subtype of granulomatous mastitis (GM) associated with Corynebacterium spp infection. We aimed to analyse the prevalence of Corynebacteria in CNGM and non-CNGM cases.

METHODS

Breast specimens diagnosed as granulomatous inflammation between 2010 and 2020 were reviewed to identify a CNGM cohort and a non-CNGM cohort. Polymerase chain reaction-based identification of Corynebacteria by 16S ribosomal RNA (16S rRNA) primers, followed by confirmatory Sanger sequencing (SS), was performed on all cases. Clinical, radiological and microbiology data were retrieved from the electronic patient records.

RESULTS

Twenty-eight CNGM cases and 19 non-CNGM cases were identified. Compared with the non-CNGM cohort, patients in the CNGM cohort were more likely to be multiparous (p=0.01), breast feeding (p=0.01) and presenting with a larger breast mass (p<0.01), spontaneous drainage (p=0.05) and skin irritation (p<0.01). No significant difference in the prevalence of Corynebacteria between the cohorts (7% vs 11%, p=0.68) by microbiological culture was identified. Compared with microbiology culture, the sensitivity and specificity of each Corynebacterial detection method were 50% and 81% for Gram stain, and 25% and 100% for 16S rRNA combined with SS. Regardless of the diagnosis, patients positive for Corynebacteria were more likely to have a persistent disease (p<0.01).

CONCLUSION

CNGM presents as a large symptomatic breast mass in multiparous breastfeeding women. The importance of adequate sampling and repeated microbiology culture in conjunction with sequencing on all GM cases with persistent disease is paramount.

Ultrasound-guided vacuum-assisted excision for idiopathic granulomatous mastitis at the abscess stage

BACKGROUND

Idiopathic granulomatous mastitis (IGM) is a rare inflammatory disease of the breast with clinical features that are often confused with those of breast cancer leading to delayed diagnosis and treatment. This retrospective study aimed to evaluate the therapeutic effectiveness and cosmetic results of drainage surgery using ultrasound-guided vacuum-assisted excision (VAE) for the treatment of IGM at the abscess stage.

METHODS

The time of recovery, cases of further surgical intervention, and cosmetic results were retrospectively collected and analyzed from patients who underwent drainage with VAE or conventional drainage between October 2017 and August 2021.

RESULTS

A total of 65 patients diagnosed with IGM at the abscess stage who underwent drainage surgery with VAE or conventional drainage surgery were enrolled. Overall, 38 (58.5%) underwent conventional drainage surgery and 27 (41.5%) underwent drainage with VAE. We found that patients who underwent VAE recovered much faster than those who underwent traditional drainage surgery (30.1 vs. 48.0 days). Nine (33.3%) patients in the VAE group required further surgical intervention after drainage, whereas 33 (86.8%) patients in the control group underwent another surgery to resect residual lesions. Additionally, patients in the VAE group were more satisfied with the breast appearance, mainly due to less influence of the scars and better symmetry of their breasts.

CONCLUSION

Compared with conventional drainage surgery, drainage surgery using VAE for IGM patients at the abscess stage improved therapeutic and cosmetic outcomes. Furthermore, postoperative management of IGM is crucial.

Treatment modalities for granulomatous mastitis, seeking the most appropriate treatment with the least recurrence rate: a systematic review and meta-analysis

BACKGROUND

Granulomatous mastitis (GM) is a rare, benign, inflammatory breast disease with an unknown etiology that predominantly affects women of reproductive age. The definitive treatment of GM is currently controversial; an appropriate therapeutic strategy has yet to be identified, and the disease's high recurrence rate remains. This study aims to determine the recurrence rate for each GM treatment strategy to identify the most appropriate treatment modality.

METHODS

The search for relevant articles was undertaken using three international databases, including Medline, Scopus, and Web of Science. Articles published in English until the end of 2021 evaluating the recurrence rate of GM were included. Using Stata 13.0, the pooled incidence and 95% confidence interval (CI) for the recurrence rate were determined.

RESULTS

Sixty-five eligible studies were included in our study. The recurrence rates of systemic steroid use, topical steroid use, antibiotic use, methotrexate use, observation, drainage, excision, antibiotic use and surgery, steroid use and surgery, antibiotic and steroid use, methotrexate and steroid use were 24% (95% CI: 21-27%), 11% (95% CI: 6-21%), 18% (95% CI: 14-22%), 13% (95% CI: 7-22%), 11% (95% CI: 7-17%), 65% (95% CI: 50-78%), 13% (95% CI: 10-16%), 23% (95% CI: 14-36%), 7% (95% CI: 5-11%), 11% (95% CI: 6-18%), and 4% (95% CI: 2-8%), respectively. Drainage had the highest recurrence rate, while combined methotrexate and steroid treatment had the lowest rate.

CONCLUSION

The optimal treatment strategy for GM depends on the disease's severity, consequences, and the patient's features. The study results indicate that combination therapy is preferable for minimizing the risk of relapse and reducing treatment complications.

Efficacy and safety of rifampicin-based triple therapy for non-puerperal mastitis: A single-arm, open-label, prospective clinical trial

OBJECTIVES

To assess the efficacy and safety of rifampicin-based triple therapy (rifampicin, isoniazid, and ethambutol) for treating NPM.

METHODS

This single-center, single-arm, prospective clinical trial was conducted at the Second Hospital of Shandong University (Jinan, China). Patients with pathologically diagnosed granulomatous lobular mastitis and periductal mastitis received triple drugs, i.e., rifampicin (450 mg/day), isoniazid (300 mg/day), and ethambutol (15 mg/kg/day), until complete response or the investigator decided to discontinue treatment. The primary endpoint was the complete response rate (CRR) assessed by the investigator. The secondary endpoints included the overall remission rate (ORR), recurrence rate (RR), and safety.

RESULTS

A total of 218 patients were enrolled in the study between January 1, 2013 and October 31, 2020. With a median follow-up time of 48 months, the CRR and the ORR were 78.44% and 94.04%, respectively. While 13 patients (5.96%) demonstrated no response and 19 relapsed (8.72%). Adverse events (AEs) were not common. The most common AEs during treatment were liver dysfunction (1.83%), gastrointestinal reactions (1.83%), fatigue (1.83%), erythema (1.38%), and menstrual disorders (0.92%).

CONCLUSION

Rifampicin, isoniazid, and ethambutol demonstrated promising response rates with acceptable safety profiles in patients with NPM. Further confirmatory trial is warranted in the future.

TRIAL REGISTRATION

The study was approved by the Ethics Committee of the Second Hospital of Shandong University and retrospectively registered at the China Clinical Trial Registration Center (registration number: ChiCTR2100049591).

Pathological manifestations of granulomatous lobular mastitis

Granulomatous lobular mastitis (GLM) is a rare inflammatory breast disease with unknown etiology, characterized by non-caseous granulomatous inflammation of the lobules, which infiltrate lymphocytes, neutrophils, plasma cells, monocytes, and eosinophils may accompany. GLM is often misdiagnosed as breast cancer due to the lack of specificity in clinical and imaging examinations, and therefore histopathology is the main basis for confirming the diagnosis. This review provides an overview of the pathological features of granulomatous lobular mastitis and cystic neutrophil granulomatous mastitis (CNGM, a pathologic subtype of GLM). As well as pathologic manifestations of other breast diseases that need to be differentiated from granulomatous lobular mastitis such as breast tuberculosis, lymphocytic mastopathy/diabetic mastopathy, IgG4-related sclerosing mastitis (IgG4-RSM), nodular disease, Wegener's granulomatosis, and plasma cell mastitis. Besides, discusses GLM and CNGM, GLM and breast cancer, emphasizing that their relationship deserves further in-depth exploration. The pathogenesis of GLM has not yet been clearly articulated and needs to be further explored, pathology enables direct observation of the microscopic manifestations of the disease and contributes to further investigation of the pathogenesis.

Granulomatous mastitis in a 50-year-old male: A case report and review of literature

BACKGROUND

Granulomatous mastitis (GM) an inflammatory disease of the breast that usually affects women of childbearing age, occurs very rarely in males.

CASE SUMMARY

We present a case study of a 50-year-old male patient with GM. The patient developed a breast lump following the cleaning of a previously embedded dirt-filled nipple. While an initial improvement was noted with antibiotic therapy, a recurrence occurred a year later, showing resistance to the previously effective antibiotics. Subsequently, the lesion was excised. The histopathological examination confirmed the diagnosis of GM.

CONCLUSION

GM should be considered a possible diagnosis of male breast masses.

Preliminary comparative genomics analysis among Corynebacterium kroppenstedtii complex necessitates a reassessment of precise species associated with mastitis

AIMS

This study aimed to characterize the first complete genome of Corynebacterium parakroppenstedtii and clarify the evolutionary relationship in the Corynebacterium kroppenstedtii complex (CKC) by using comparative genomics analysis.

METHODS AND RESULTS

The genome of isolate yu01 from a breast specimen was sequenced, and 35 CKC genomes were collected. Analysis of 16S rRNA, rpoB, and fusA suggested ambiguous identification, whereas ANI analysis assigned isolate yu01 as Coryne. parakroppenstedtii. The fourth genospecies "Corynebacterium aliikroppenstedtii" was identified in CKC. Comparative genomics analysis suggested that the genomic arrangement in CKC was highly conserved. A total of 43 potential virulence genes and 79 species-specific genes were detected. Most genome-based phylogenetic analysis were incapable of resolving the interspecific evolutionary relationships among CKCs. A total of 20 core genes were found to be distinguishable in CKC.

CONCLUSIONS

This study suggested the limited divergence and unavailability of normal single gene-based identification in CKC and questioned the precise species of strains associated with mastitis, identified as Coryne. kroppenstedtii in previous studies. The 20 genes showed potential to enhance the methods for the identification and epidemiological investigation of CKC.

Rotational gland dissection for refractory granulomatous mastitis: A single-center retrospective study

BACKGROUND

Refractory granulomatous mastitis (RGM) is a chronic benign breast disease that commonly occurred in women of childbearing age and is usually treated with surgery, with numerous cases suffering from unsatisfied postoperative recovery of breast shape, high rates of surgical complications, and even high recurrence. This study tries to evaluate the efficacy of an innovative surgical procedure, the rotational gland dissection for the treatment of RGM.

METHODS

129 patients with RGM who underwent surgical treatment at the Second Affiliated Hospital of Xi'an Jiaotong University between Apr. 2017 and May. 2021 were retrospectively included in this study. The article analyzed the age, local symptoms, lesion location, and size, days in hospital, recurrence rate, and satisfaction rate of the patients.

RESULTS

Patients ranged in age from 19 to 58 years, with a median age of onset of 32 years. In 63 patients (48.84%), their lesions coverage exceeded two quadrants, and 52.71% of patients had lesions larger than 10 cm2. The average days in hospital of patients was 7.5 days, and 85.27% of them were satisfied with their post-surgery breast appearance. Within the median follow-up of 56 months, only 3.10% of patients experienced a recurrence of mastitis on the operation side.

CONCLUSION

This novel surgical procedure we created is an effective treatment for RGM with a high success rate, high patient satisfaction, and low recurrence rate, and is significantly superior to other studies for it has the largest sample size and longest follow-up in this field.

The effectiveness of needle aspiration versus traditional incision and drainage in the treatment of breast abscess: a meta-analysis

BACKGROUND

Breast abscess is a common and intractable clinical condition and the use of needle aspiration (NA) or incision and drainage (ID) in treatment is controversial. This meta-analysis aimed to systematically compare the clinical effectiveness of NA and ID in treating breast abscesses.

METHODS

The Web of Science, ScienceDirect, PubMed, Cochrane Library, EMBASE, China National Knowledge Infrastructure, and Wanfang Data were searched for randomized controlled trials (RCTs) published from inception to January 7, 2022. The ROB-2 tool assessed risk of bias; the GRADE methodology rated certainty in outcomes; and Stata 16.0 performed data analyses.

RESULTS

Nine RCTs were included, including 703 patients. The results showed there was no significant difference in cure rate between the two groups (relative risk [RR] = 0.96, 95% confidence interval [CI] [0.86, 1.07]; p = .469), and after subgroup analysis, we found that it was not related to the use of ultrasound guidance or not. There was no significant difference in the recurrence rate (RR = 0.68, 95% CI [0.35, 1.30]; p = .241). Furthermore, the NA group was associated with shorter healing time (weighted mean differences = -11.02, 95% CI [-15.14, -6.90]; p < .001), lower incidence of breast fistula (RR = 0.21, 95% CI [0.06, 0.72]; p = .013), lower interrupted breastfeeding rate (RR = 0.28, 95% CI [0.20, 0.39]; p < .001), and higher satisfaction rate of appearance (RR = 1.51, 95% CI [1.03-2.21]; p = .035).

CONCLUSION

NA has better advantages in terms of healing time, avoidance of breast fistula, continuous breastfeeding, and patient satisfaction. Although NA and ID have similar cure and recurrence rates, NA, with or without ultrasound guidance, could be used as a first-line treatment for breast abscesses. Patients with large volumes, multicompartmental abscesses, or those who have been ineffective against multiple NA, should be considered for ID.KEY MESSAGESBreast abscess is a common and intractable clinical condition in general surgery.Compared with ID for breast abscesses, NA has better advantages in terms of healing time, avoidance of breast fistula, continuous breastfeeding, and patient satisfaction and could be used as a first-line treatment for breast abscesses.Patients with large volumes, multicompartmental abscesses, or those who have been ineffective against multiple NA, should be considered for ID.

Risk Factors for Granulomatous Mastitis and Establishment and Validation of a Clinical Prediction Model (Nomogram)

Background

This study aimed to explore the risk factors and clinical characteristics of granulomatous mastitis (GM) using a case-control study and establish and validate a clinical prediction model (nomogram).

Methods

This retrospective case-control study was conducted in three hospitals in China from June 2017 to December 2021. A total of 1634 GM patients and 186 healthy women during the same period were included and randomly divided into the modeling and validation groups in a 7:3 ratio. To identify the independent risk factors of GM, univariate and multivariate logistic analyses were conducted and used to develop a nomogram. The prediction model was internally and externally validated using the Bootstrap technique and validation cohort. The receiver operating characteristic (ROC) curve and calibration curve were used to evaluate the discrimination and calibration of the prediction model. Decision curve analysis (DCA) and clinical impact curve (CIC) were used to evaluate the clinical significance of the model.

Results

The average age of GM patients was 33.14 years (mainly 20-40). The incidence was high within five years from delivery and mainly occurred in the unilateral breast. The majority of the patients exhibited local skin alterations, while some also presented with systemic symptoms. On multivariate logistic analysis, age, high prolactin level, sex hormone intake, breast trauma, nipple discharge or invagination, and depression were independent risk factors for GM. The mean area under the curve (AUC) in the modeling and validation groups were 0.899 and 0.889. The internal and external validation demonstrated the model's predictive ability and clinical value.

Conclusion

Lactation-related factors are the main risk factors of GM, leading to milk stasis or increased ductal secretion. Meanwhile, hormone disorders could affect the secretion and expansion of mammary ducts. All these factors can obstruct or injure the duct, inducing inflammatory reactions and immune responses. Additionally, blunt trauma, depressed mood, and diet preference can accelerate the process. The nomogram can effectively predict the risk of GM.

LC/MS-based untargeted lipidomics reveals lipid signatures of nonpuerperal mastitis

BACKGROUND

Nonpuerperal mastitis (NPM) is a disease that presents with redness, swelling, heat, and pain during nonlactation and can often be confused with breast cancer. The etiology of NPM remains elusive; however, emerging clinical evidence suggests a potential involvement of lipid metabolism.

METHOD

Liquid chromatography‒mass spectrometry (LC/MS)-based untargeted lipidomics analysis combined with multivariate statistics was performed to investigate the NPM lipid change in breast tissue. Twenty patients with NPM and 10 controls were enrolled in this study.

RESULTS

The results revealed significant differences in lipidomics profiles, and a total of 16 subclasses with 14,012 different lipids were identified in positive and negative ion modes. Among these lipids, triglycerides (TGs), phosphatidylethanolamines (PEs) and cardiolipins (CLs) were the top three lipid components between the NPM and control groups. Subsequently, a total of 35 lipids were subjected to screening as potential biomarkers, and the chosen lipid biomarkers exhibited enhanced discriminatory capability between the two groups. Furthermore, pathway analysis elucidated that the aforementioned alterations in lipids were primarily associated with the arachidonic acid metabolic pathway. The correlation between distinct lipid populations and clinical phenotypes was assessed through weighted gene coexpression network analysis (WGCNA).

CONCLUSIONS

This study demonstrates that untargeted lipidomics assays conducted on breast tissue samples from patients with NPM exhibit noteworthy alterations in lipidomes. The findings of this study highlight the substantial involvement of arachidonic acid metabolism in lipid metabolism within the context of NPM. Consequently, this study offers valuable insights that can contribute to a more comprehensive comprehension of NPM in subsequent investigations.

TRIAL REGISTRATION

Shuguang Hospital Affiliated to Shanghai University of Traditional Chinese Medicine (Number: 2019-702-57; Date: July 2019).

Clinical characteristics and therapeutic strategy of granulomatous mastitis accompanied by Corynebacterium kroppenstedtii: a retrospective cohort study

BACKGROUND

Increasing evidence has suggested that Corynebacterium kroppenstedtii is associated with some cases of granulomatous mastitis, mostly based on pathology or microbiology. We aimed to identify the clinical characteristics and treatment regimens for granulomatous mastitis with Corynebacterium kroppenstedtii infection. Understanding these clinical features is essential for patient care.

METHODS

We retrospectively collected data on 201 patients who were pathologically diagnosed with granulomatous mastitis and had microbiological results of either Corynebacterium kroppenstedtii or no bacterial growth and recorded and analysed their demographics, clinical characteristics, and clinical outcomes.

RESULTS

There were 107 patients in the CK group and 94 patients in the negative group. Sinus formation (x² = 13.028, p = 0.000), time to complete remission at the first treatment period (Z = -3.027, p = 0.002), diameter of breast mass at first-time medical consultancy (Z = -2.539, p = 0.011) and recurrence (x² = 4.953, p = 0.026) were statistically significant. Age (Z = -1.046, p = 0.295), laterality (x² = 4.217, p = 0.121), time to presentation since the last delivery (x² = 0.028, p = 0.868), BMI (Z = -0.947, p = 0.344), lactation time (Z = -1.378, p = 0.168), parity (x² = 1.799, p = 0.180), gravida (Z = -0.144, p = 0.885), history of lactational mastitis or abscess (x² = 0.115, p = 0.734), local trauma (x² = 0.982, p = 0.322), hyperprolactinemia (x² = 0.706, p = 0.401), erythema nodosum (x² = 0.292, p = 0.589), and nipple discharge (x² = 0.281, p = 0.596) did not demonstrate statistical significance. Regarding recurrence related to therapeutic strategy, except for surgery combined with immunosuppressants (x² = 9.110, p = 0.003), which was statistically significant, none of the other treatment regimens reached statistical significance. The recurrence rate of patients in the CK group using rifampicin in their treatment course was 22.0% (x² = 4.892, p = 0.027).

CONCLUSIONS

Granulomatous mastitis accompanied by Corynebacterium kroppenstedtii more easily forms sinuses and has a higher recurrence rate. Both of the clinical characteristics may indicate that Corynebacterium kroppenstedtii plays an important role in the development and progression of granulomatous mastitis. Lipophilic antibiotics may be essential for granulomatous mastitis with Corynebacterium kroppenstedtii infection.

Predisposing Factors for Granulomatous Lobular Mastitis: A Case-Control Study

Background

Despite the rising incidence rate of granulomatous lobular mastitis (GLM), uncertainties persist about its etiologic and predisposing factors to guide clinical treatment and early prevention. The objective of this study is to explore the predisposing factors for GLM.

Patients and methods

This case-control study was conducted from 2018 to 2021 at Beijing Hospital of Traditional Chinese Medicine, Capital Medical University. Patients with GLM (cases) were matched with healthy examinees (controls) in a 1:1 ratio according to gender and living area. We analyzed their demographic features and investigated 75 factors that may be relevant to GLM using a standard questionnaire. Univariate and multivariable binary conditional logistic regression analyses were used to compare the differences between the two groups and evaluate the predisposing factors that may induce GLM.

Results

There were 594 female GLM patients and 594 matched controls included in the study. The average age of the cases was 32.78 years (mainly 20 to 40). The incidence was high within five years after childbirth, and lesions were mainly in the unilateral breast. Univariate and multivariable conditional logistic regression analyses obtained six relevant factors and six high-risk factors. The six relevant factors included age, marriage, emotional abnormality, high prolactin, psychiatric drug intake, and sex hormone intake. Additionally, the independent high-risk factors for GLM included gestation, nipple invagination, blunt trauma, non-iatrogenic massage, lactation disorder, and nipple discharge (odds ratio (OR)=17.378, 8.518, 4.887, 3.116, 2.522, 1.685, P<0.05). Menopause was an independent protective factor (OR=0.249, P<0.05).

Conclusion

The factors that increase milk and secretion production in the mammary duct are the main risk factors of GLM, especially when the nipples are invaginated. These factors can obstruct the duct and induce inflammation. Additionally, hormonal disorders, extrinsic trauma, and emotional abnormalities can accelerate the occurrence of GLM.

Clinical characteristics and microbiota analysis of 44 patients with granulomatous mastitis

Introduction

Granulomatous mastitis (GM) is a chronic inflammatory breast disease. In recent years, the role of Corynebacterium in GM onset has received more and more attention. This study aims to detect the dominant bacterium in GM patients and analyze the association between clinical characteristics and infectious factors.

Methods

In this study, 88 samples from 44 GM patients, six acute lactation mastitis (ALM) patients, and 25 non-inflammatory breast disease (NIB) patients were divided into a GM pus group, a GM tissue group, an ALM pus group, and a NIB tissue group; then, 16S ribosomal DNA sequencing was used to explore their microbiota. The clinical data of all 44 GM patients were also retrospectively collected and analyzed to determine their relationship with infection.

Results

The median age of the 44 GM patients was 33 years, and 88.6% of patients had primary-onset cases, while 11.4% were recurrences; additionally, 89.5% of patients were postpartum and 10.5% were nulliparous. The serum prolactin level was abnormal in nine patients (24.3%). Samples from 15 GM patients (34.1%) had a Corynebacterium abundance of >1% (1.08-80.08%), with eight (53.3%) displaying an abundance of >10%. Corynebacterium was the only genus with significant differences between the GM pus group and the other three groups (p < 0.05). Corynebacterium kroppenstedtii was the predominant Corynebacterium species. Among clinical characteristics, a statistical difference in breast abscess formation was observed according to Corynebacterium abundance in Corynebacterium-positive and- negative patients (p < 0.05).

Discussion

This study explored the relationship between Corynebacterium infection and GM, compared the clinical characteristics between Corynebacterium-positive and- negative patients, and provided support for the role of Corynebacterium species-in particular, C. kroppenstedtii-in the pathogenesis of GM. The detection of Corynebacterium can predict GM onset, especially in patients with high prolactin levels or a history of recent lactation.

Udder Health Monitoring for Prevention of Bovine Mastitis and Improvement of Milk Quality

To maximize milk production, efficiency, and profits, modern dairy cows are genetically selected and bred to produce more and more milk and are fed copious quantities of high-energy feed to support ever-increasing milk volumes. As demands for increased milk yield and milking efficiency continue to rise to provide for the growing world population, more significant stress is placed on the dairy cow's productive capacity. In this climate, which is becoming increasingly hotter, millions of people depend on the capacity of cattle to respond to new environments and to cope with temperature shocks as well as additional stress factors such as solar radiation, animal crowding, insect pests, and poor ventilation, which are often associated with an increased risk of mastitis, resulting in lower milk quality and reduced production. This article reviews the impact of heat stress on milk production and quality and emphasizes the importance of udder health monitoring, with a focus on the use of emergent methods for monitoring udder health, such as infrared thermography, biosensors, and lab-on-chip devices, which may promote animal health and welfare, as well as the quality and safety of dairy products, without hindering the technological flow, while providing significant benefits to farmers, manufacturers, and consumers.