Risk Factors for Development and Recurrence of Primary Breast Abscesses

Prediction models for postoperative recurrence of non-lactating mastitis based on machine learning

OBJECTIVES

This study aims to build a machine learning (ML) model to predict the recurrence probability for postoperative non-lactating mastitis (NLM) by Random Forest (RF) and XGBoost algorithms. It can provide the ability to identify the risk of NLM recurrence and guidance in clinical treatment plan.

METHODS

This study was conducted on inpatients who were admitted to the Mammary Department of Shuguang Hospital affiliated to Shanghai University of Traditional Chinese Medicine between July 2019 to December 2021. Inpatient data follow-up has been completed until December 2022. Ten features were selected in this study to build the ML model: age, body mass index (BMI), number of abortions, presence of inverted nipples, extent of breast mass, white blood cell count (WBC), neutrophil to lymphocyte ratio (NLR), albumin-globulin ratio (AGR) and triglyceride (TG) and presence of intraoperative discharge. We used two ML approaches (RF and XGBoost) to build models and predict the NLM recurrence risk of female patients. Totally 258 patients were randomly divided into a training set and a test set according to a 75%-25% proportion. The model performance was evaluated based on Accuracy, Precision, Recall, F1-score and AUC. The Shapley Additive Explanations (SHAP) method was used to interpret the model.

RESULTS

There were 48 (18.6%) NLM patients who experienced recurrence during the follow-up period. Ten features were selected in this study to build the ML model. For the RF model, BMI is the most important influence factor and for the XGBoost model is intraoperative discharge. The results of tenfold cross-validation suggest that both the RF model and the XGBoost model have good predictive performance, but the XGBoost model has a better performance than the RF model in our study. The trends of SHAP values of all features in our models are consistent with the trends of these features' clinical presentation. The inclusion of these ten features in the model is necessary to build practical prediction models for recurrence.

CONCLUSIONS

The results of tenfold cross-validation and SHAP values suggest that the models have predictive ability. The trend of SHAP value provides auxiliary validation in our models and makes it have more clinical significance.

Breast infections: A review of current literature

Breast infections are common, affect women of all ages, and are associated with significant morbidity. Despite overall prevalence, treatment varies significantly based on provider or institution and no central treatment guidelines exist to direct the management of breast infections. This article provides a summary of the current trends in management of breast infections. The etiology, epidemiology, risk factors, presentation, diagnosis, and treatment of mastitis and breast abscesses (and their relative subdivisions) are explored based on the current literature. Trends in microbiology are reviewed and an approach to antibiotic coverage is proposed. Overall, there is a lack of randomized-controlled trials focused on the treatment of breast infections. This has resulted in an absence of clinical practice guidelines for the management of breast abscesses and variable practice patterns. The development of best-care protocols or pathways could provide more uniformity in care of breast infections.

Zuska's disease in a male patient. The critical role of ultrasound imaging in diagnosis and management of this rare entity

Zuska's disease is a pathologic entity characterized by the formation of subareolar breast abscess caused by the obstruction of lactiferous ducts. Although Zuska's disease is found relatively often in female patients, only 19 male cases have been reported. That makes Zuska's diagnosis challenging in males, leading to significant morbidity and high recurrence rates. Clinical evaluation and imaging techniques, especially ultrasound and mammography, are considered the cornerstones for the diagnosis of Zuska's disease, whereas fine-needle aspiration cytology is necessary in order to exclude malignancy. Multiple treatment approaches have been used including conservative antibiotic therapy, drainage of the abscess and surgical excision of the lactiferous ducts. We present the case of a 57 year old male who was diagnosed with Zuska's disease and treated via ultrasound-guided drainage of the abscess. Having a high level of suspicion, performing appropriate imaging tests and offering definite treatment, is the only way to decrease morbidity and recurrence.

The nipple-areolar complex: anatomy, methods and pathologic findings, between senologist and dermatologist

The purpose of this presentation is to show the ultrasonography findings of normal variants and benign and malignant diseases that affect the nipple-areolar complex. Many of which have unspecific clinical and radiological presentations that can present a challenge for medical specialists. Experienced specialists need to know the different imaging modalities used to study the nipple-areolar complex and the aspect not exactly senology, as well as dermatologist who approach the ultrasound must know the anatomy of this complex area. We will show you a combined clinical and radiological approach to evaluate the nipple-areolar complex, the findings for the normal morphology and the most common benign and malignant diseases that can affect this region. We discuss the characteristics of the different ultrasonography findings and provide guidance on how to avoid artifacts and pitfalls.

Corrective surgery for nipple depression in patients with plasmacytic mastitis - A single-center experience

Background

Plasma cell mastitis (PCM) is a complex breast disease in the clinic. Currently, there are no unified diagnostic criteria for the disease and no standard treatment methods. The effects of hormone, Conventional Chinese medicine and other treatments are uncertain, with long treatment duration and notable side effects. Surgery is the preferred treatment, but the recurrence rate after conventional surgery is very high, which may be related to depression of the nipple. This study aimed to evaluate the efficacy of a novel corrective procedure in patients with cellular mastitis and depressed nipples.

Methods

Patients with PCM who received surgical treatment in the Third Medical Center of PLA General Hospital from January 1996 to January 2018 were retrospectively analyzed. According to the presence or absence of nipple depression before surgery, the patients were divided into the nipple depression group and the non-nipple depression group. In the nipple depression group, patients were subdivided into a novel corrective surgery group ("one" suture or half pocket suture) and a conventional corrective surgery group (oil yarn traction valgus correction of nipple depression). Demographic, clinical, therapeutic, and postoperative relapse data were collected and analyzed.

Results

Compared with the patients in the non-nipple depression group, patients in the nipple depression group had a significantly higher recurrence risk after surgery (HR = 2.129 95% CI: 1.110-4.083, p = 0.023). Patients who underwent novel corrective surgery had a significantly lower recurrence risk than those who underwent conventional corrective surgery (HR = 0.363 95% CI: 0.150-0.880, p = 0.025). In addition, the novel corrective surgery significantly reduced the postoperative recurrence risk (HR = 0.088 95% CI: 0.009-0.886, p = 0.037).

Conclusion

How to correct nipple depression is a critical factor for postoperative recurrence of PCM, and this novel corrective surgery for nipple depression can effectively reduce the postoperative recurrence rate in patients with nipple depression.

Biomedical Indicators of Patients with Non-Puerperal Mastitis: A Retrospective Study

BACKGROUND

Non-puerperal mastitis (NPM), a recurrent chronic inflammation of non-lactating breast, often proves tremendous difficulty in treatment, and it may give rise to its complicated symptoms and unclear etiology. Furthermore, the clinical morbidity rate of NPM has been increasing in recent years.

METHODS

Overall, 284 patients diagnosed with NPM were consecutively recruited as cases in this study, and patients with benign breast disease (n = 1128) were enrolled as control. The clinical, biomedical, and pathological indicators were analyzed. Univariate and multivariate logistic analysis were used to distinguish risks between NPM and benign breast mass patients. Furthermore, according to the pathological characteristics, the patients of NPM were classified into two subgroups: mammary duct ectasia (MDE) and granulomatous lobular mastitis (GLM). The differences of biomedical indicators between MDE and GLM groups were also analyzed.

RESULTS

Compared with benign breast mass group, the level of high-density lipoprotein (HDL-C) significantly decreased, while lipoprotein(a) (Lp(a)) and blood glucose (GLU) both increased in NPM group. According to univariate and multivariate logistic analysis, the onset age and HDL-C were generally decreased, while Lp(a) and GLU were increased in NPM group. The onset age, HDL-C, Lp(a), and GLU were modeled to distinguish NPM and benign breast mass. Significant differences were also observed between MDE and GLM patients in biomedical indicators, such as lipoprotein(a) (Lp(a)), lactate dehydrogenase (LDH), creatine kinase (CK), total cholesterol (TC), and so on.

CONCLUSIONS

Our results indicated for the first time that biomarkers were associated with NPM. The biomedical indicators involved in lipid metabolism might be important factors in the development and treatment of NPM. In addition, MDE and GLM are two diseases with different inflammatory states of NPM. These findings would be helpful for a better understanding of NPM and give us some insights to develop new diagnostic and therapeutic strategies.

Microbiology of breast abscesses

INTRODUCTION

Treatment of breast abscesses is based on drainage and antibiotic therapy directed at the bacteria causing the infection. The aim of this study was to know the etiological agents of breast abscesses.

METHODS

Patients who had a culture-positive breast abscess between September 2015 and January 2020 were included in the study. Culture results were consulted in the laboratory database. It was collected from medical records if the patients presented the following risk factors: breastfeeding, diabetes or smoking. Abscesses secondary to surgical wound infection were excluded.

RESULTS

Sixty patients were included, 58 women and 2 men. Staphylococcus aureus was the most frequent agent in lactating women. Anaerobic bacteria were isolated in 28 (61%) of 46 abscesses in non-lactating patients. In non-lactating patients, the frequency of anaerobes in abscesses was lower in diabetics than in the rest (0/5 vs 26/38; P = .013). In non-lactating and non-diabetic patients, the proportion of abscesses with anaerobes was higher in smokers than in non-smokers (21/24 vs 5/14; P = .003). Aerobic gram-positive cocci were the most frequent agents in diabetics.

CONCLUSION

Anaerobes were the most frequent agents, followed by S. aureus. The etiology of breast abscesses varied with the risk factors studied.

Bacterial infections in patients with nipple piercings: a qualitative systematic review of case reports and case series

The main objective of this review is to identify the most frequently isolated bacteria in patients with infections related to nipple piercings in case reports and case series. In addition, the aim is to describe clinical manifestations and antecedents. There is a protocol of this review. The terms "bacterial infections", "nipple piercing" and their synonyms were considered. Pubmed/Medline, Scopus, Embase, Web of Science core collection and Ovid/Medline databases were searched until November 15, 2021 without date or language restrictions. Two authors extracted the articles and three other authors performed the selection, first by title and abstract, and second by full-text revision. Discrepancies were resolved with yet two other authors. Quality was assessed using the Joanna Briggs checklists. Finally, data extraction was realized. A total of 1,531 articles were extracted, of which 20 articles were included, and one article was added by hand-searching. The final number of articles included was 21, all of them with acceptable quality of evidence. Twenty-seven patients were considered (23 women and 4 men), aged between 15-60 years old. The most frequent bacterial genus in case reports and case series was Staphylococcus (n=10), and the most frequent species was M. fortuitum (n=6), although etiology seems to be diverse. The breast was the main affected organ, and the most frequent findings were fluid collection, pain, erythema, granulation tissue and swelling. The suspicion of infection by this bacterial species could be taken into account when it is associated with nipple piercings; however, larger studies are required to give a conclusion based on the evidence.

Microbiology of breast abscesses

INTRODUCTION

Treatment of breast abscesses is based on drainage and antibiotic therapy directed at the bacteria causing the infection. The aim of this study was to know the etiological agents of breast abscesses.

METHODS

Patients who had a culture-positive breast abscess between September 2015 and January 2020 were included in the study. Culture results were consulted in the laboratory database. It was collected from medical records if the patients presented the following risk factors: breastfeeding, diabetes or smoking. Abscesses secondary to surgical wound infection were excluded.

RESULTS

Sixty patients were included: 58 women and 2 men. Staphylococcus aureus was the most frequent agent in lactating women. Anaerobic bacteria were isolated in 28 (61%) of 46 abscesses in non-lactating patients. In non-lactating patients, the frequency of anaerobes in abscesses was lower in diabetics than in the rest (0/5 vs 26/38; P=.013). In non-lactating and non-diabetic patients, the proportion of abscesses with anaerobes was higher in smokers than in non-smokers (21/24 vs 5/14; P=.003). Aerobic gram-positive cocci were the most frequent agents in diabetics.

CONCLUSION

Anaerobes were the most frequent agents, followed by S.aureus. The etiology of breast abscesses varied with the risk factors studied.

Squamous metaplasia of lactiferous ducts (SMOLD): an under-recognised entity

Breast abscesses are a common surgical problem, typically occurring secondary to lactation mastitis. Recurrent subareolar abscesses are rarely reported and may be poorly recognised as a presentation of squamous metaplasia of lactiferous ducts, known eponymously as 'Zuska's disease'. Other synonyms include subareolar breast abscess and lactiferous or mammary fistulas. Recognition of this painful entity is crucial for optimal outcomes since typical breast abscess management of recurrent aspiration or incision and drainage can lead to recurrence and chronic complications, such as fistula formation.

A subareolar breast abscess in a man: A case report and literature review

Subareolar breast abscesses (SBAs) in men are extremely rare. To date, only 15 men with SBA have been reported in the English literature. We present a case of SBA in a 28-year-old man who visited our surgical clinic with a painful swelling in his right breast for 10 days. Physical examination showed a tender, hot mass in the right subareolar area with erythema. Ultrasound of the right breast showed radiological features of a breast abscess. Fine-needle aspiration yielded brownish yellow pus. Based on these findings, a diagnosis of right SBA was established. This is the first documented case of SBA in men from the KSA. Additionally, this case report sheds light on the current clinical and therapeutic approaches to managing cases of SBA in men.

Pitfalls of Breast Evaluation in the Emergency Department

Breast complaints in the emergency department (ED) include trauma, infection, pain, masses, and nipple discharge. Breast cancer mimics other inflammatory conditions such as mastitis and abscess. Differentiating infectious processes versus cancer can become problematic when no imaging is used. While mammogram is included in the initial imaging for outpatient breast evaluation, ultrasound is more available in the ED. We present a case of a patient seen in the ED for breast pain and mass. The patient had no imaging done, yet the ED physician attempted to drain the mass unsuccessfully and prescribed antibiotics. The patient followed up at a breast center where clinical Stage IIA right breast invasive ductal carcinoma (IDC) was diagnosed. This case highlights the importance of breast imaging before drainage for suspected abscess and the importance of follow-up for all breast complaints that present in the ED to rule out a malignancy.

Characterization of Pediatric Breast Abscesses and Optimal Treatment: A Retrospective Analysis

BACKGROUND

Literature on pediatric breast abscesses is sparse; therefore, treatment is based on adult literature which has shifted from incision and drainage (I&D) to needle aspiration. However, children may require different treatment due to different risk factors and the presence of a developing breast bud. We sought to characterize pediatric breast abscesses and compare outcomes.

MATERIALS AND METHODS

A retrospective review of patients presenting with a primary breast abscess from January 2008 to December 2018 was conducted. Primary outcome was persistent disease. Antibiotic utilization, treatment required, and risk factors for abscess and recurrence were also assessed. A follow-up survey regarding scarring, deformity, and further procedures was administered. Fisher's exact and Kruskal-Wallis tests for group comparisons and multivariable regression to determine associations with recurrence were performed.

RESULTS

Ninety-six patients were included. The median age was 12.8 y [IQR 4.9, 14.3], 81% were women, and 51% were African-American. Most commonly, patients were treated with antibiotics alone (47%), followed by I&D (27%), and aspiration (26%). Twelve patients (13%) had persistent disease. There was no difference in demographic or clinical characteristics between those with persistent disease and those who responded to initial treatment. The success rates of primary treatment were 80% with antibiotics alone, 90% with aspiration, and 96% with I&D (P = 0.35). The median time to follow-up survey was 6.5 y [IQR 4.4, 8.5]. Four patients who underwent I&D initially reported significant scarring.

CONCLUSIONS

Treatment modality was not associated with persistent disease. A trial of antibiotics alone may be considered to minimize the risk of breast bud damage and adverse cosmetic outcomes with invasive intervention.

Multimodality approach to the nipple-areolar complex: a pictorial review and diagnostic algorithm

The anatomic and histologic characteristics of the nipple-areolar complex make this breast region special. The nipple-areolar complex can be affected by abnormal development and a wide spectrum of pathological conditions, many of which have unspecific clinical and radiological presentations that can present a challenge for radiologists. The nipple-areolar complex requires a specific imaging workup in which a multimodal approach is essential. Radiologists need to know the different imaging modalities used to study the nipple-areolar complex, as well as their advantages and limitations. It is essential to get acquainted with the acquisition technique for each modality and the spectrum of findings for the different conditions. This review describes and illustrates a combined clinical and radiological approach to evaluate the nipple-areolar complex, emphasizing the findings for the normal morphology, developmental abnormalities, and the most common benign and malignant diseases that can affect this region. We also present a diagnostic algorithm that enables a rapid, practical approach to diagnosing condition involving the nipple-areolar complex.

Nonpuerperal breast abscess due to Prevotella bivia

Contrary to puerperal abscess, nonpuerperal breast abscess is often caused by anaerobic bacteria; polymicrobial aerobic-anaerobic infections are also frequent. Empiric first-choice treatment with broad-spectrum antibiotics should be considered.

Zuska's breast disease: Breast imaging findings and histopathologic overview

Zuska's disease describes the clinical condition of recurrent central or periareolar nonpuerperal abscesses associated with lactiferous fistulas. Pathogenesis involves the occlusion of an abnormal duct through an epithelial desquamation process that causes ductal dilatation, stasis of secretions, and periductal inflammation. Patients with Zuska's disease may develop chronic draining sinuses near the areola from lactiferous ducts fistula; therefore, the underlying abnormal duct system must be located and excised for proper treatment. Zuska's disease is often misdiagnosed and mistreated and is associated with significant morbidity, including the recurrence of abscess and cutaneous fistula formation. This case series aimed to help clinicians investigate and manage this disorder. The clinical and imaging findings, histopathologic correlation, and treatment of Zuska's disease are discussed.

Breast Abscesses Caused by Anaerobic Microorganisms: Clinical and Microbiological Characteristics

The objectives of this study were to report the antimicrobial susceptibility of 35 clinically significant anaerobic bacteria isolated from breast abscesses between March 2017 and February 2020 in a tertiary hospital in Granada (Spain) and to describe key clinical features of the patients. Species identification was performed mainly by MALDI-TOF MS. Antimicrobial susceptibility tests were carried out against benzylpenicillin, amoxicillin-clavulanic acid, imipenem, moxifloxacin, clindamycin, metronidazole, and piperacillin-tazobactam using the gradient diffusion technique and European Committee on Antimicrobial Susceptibility Testing EUCAST breakpoints (except for moxifloxacin). The most frequent anaerobes were Finegoldia magna (31.4%; n = 11), Actinomyces spp. (17.1%; n = 6), Propionibacterium spp. (17.1%; n = 6), and Prevotella spp. (14.2%; n = 5). Imipenem, amoxicillin-clavulanic acid, and piperacillin-tazobactam were universally active against all genera tested. High overall resistance rates to clindamycin were observed, especially for Gram-positive anaerobic cocci (56.2%) and Gram-positive anaerobic bacilli (38.4%). High resistance rates to metronidazole were also observed for Gram-positive (76.9%) and Gram-negative anaerobic bacilli (50%). High resistance rates to moxifloxacin were found for Gram-negative anaerobic bacilli (50%) and Gram-positive anaerobic cocci (31.2%). No breast abscess cases of Bacteroides spp. were detected. Routine antimicrobial susceptibility testing for anaerobes in breast abscesses may contribute to allow empirical therapies to be selected in accordance with local data on resistant strains.

Cystic neutrophilic granulomatous mastitis: an update

Cystic neutrophilic granulomatous mastitis (CNGM) is a rare subtype of granulomatous mastitis with a highly distinct histological pattern often associated with Corynebacterium species. CNGM is characterised by suppurative lipogranulomas that are composed of central lipid vacuoles rimmed by neutrophils and an outer cuff of epithelioid histiocytes. Some of the lipid vacuoles may contain sparse, rod-shaped, gram-positive bacilli that can be easily missed or dismissed. The surrounding mixed inflammatory infiltrate contains Langhans-type giant cells, lymphocytes and neutrophils. CNGM occurs in reproductive age women with a history of pregnancy and typically presents as a palpable mass that can be painful. CNGM has many mimickers, most significantly breast carcinoma. In many cases, CNGM has significant pathological and clinical overlap with other forms of granulomatous mastitis. Given the association with Corynebacterium species, early diagnosis of CNGM is essential in offering patients the most appropriate treatment. Prolonged antibiotic therapy specifically directed to corynebacteria is required, sometimes even beyond resolution of clinical symptoms. This comprehensive review of the existing literature on CNGM describes clinical-pathological features, microbiological findings, challenges associated with the microscopic differential diagnosis, clinical implications of this diagnosis and emerging treatment options. Morphological criteria and suggested comments to convey the degree of diagnostic certainty are also proposed for standard pathology reporting.

Abscess Drainage with or Without Antibiotics in Lactational Breast Abscess: Study Protocol for a Randomized Controlled Trial

Background

Lactational breast abscess, a complication from lactational mastitis, is a common cause of breastfeeding discontinuation. No consensus has been reached regarding the necessity of antibiotics in this disease. The purpose of this trial is to determine if surgical drainage is non-inferior to drainage together with a standard course of antibiotics, in the treatment of lactational breast abscess.

Methods

Breastfeeding females with breast abscess from 18 to 50 years old are eligible for study inclusion. An expected number of 306 patients will be randomly allocated in parallel to the intervention arm (simple drainage without antibiotics) or the control arm (abscess drainage with standard 5-day-course of antibiotics). The primary outcomes include the time to resolution of breast abscess and disease recurrence rate. Secondary outcomes of interests are 3-day-improvement proportion, rate of continuing breastfeeding, treatment failure rate, procedural-related complications, and length of hospital stay. An expected non-inferiority margin for the difference in the primary outcome of interest is set at 1 day, on the basis of a one-sided 97.5% confidence interval.

Discussion

This trial will provide first-hand evidence on whether simple abscess drainage is non-inferior to drainage together with a standard course of antibiotics, in lactational mothers with breast abscess. The indication of antibiotic prophylaxis could be revised if non-inferiority is set up, and guidelines for lactational breast abscess require amendments correspondingly.

Trial Registration

This study has been registered in the Chinese Clinical Trial Registry, and the trial registration number is ChiCTR1900024008.

Breast infections - Microbiology and treatment in an era of antibiotic resistance

INTRODUCTION

Primary breast abscesses occur in <1% of non-lactating women, rising to 11% in women with lactational mastitis. In patients undergoing breast cancer surgery, the inflammatory response to post-operative surgical site infection (SSI) has been implicated in recurrence. Anti-microbial resistance increasingly hampers treatment in each group.

AIMS

Describe the demographic and predisposing characteristics of patients with primary breast abscesses and secondary infections, identify the microbial and antimicrobial patterns and formulate an evidence-based protocol for treating breast infections.

METHODS

Retrospective cohort study of all breast infections (primary and post-operative) treated at UHL from 2014 to 2017. Data collected from microbiology databases and patient records was analysed using Minitab V18.

RESULTS

537 cultures from 108 patients were analysed. 47 (43.5%) had primary abscesses, 12 (11.1%) were lactational and 49 (45.4%) were post-operative SSI. For primary infections, the mean age was 41.9 (±12.2) and reinfection rate 33%. For SSIs the mean age was 51.8 (±14.52) and reinfection rate 11.8%. Overall, 29.3% were smokers, 6.4% diabetic and 2.9% pregnant. 60 (43%) patients required radiological drainage and 2 (1%) surgical drainage. 57.5% had mixed growth. The most common isolate was Staphylococcus aureus; cultured in 16.7% of primary abscesses and 24% of SSIs. 13 empiric antibiotic regimes were prescribed before 26.4% of patients changed to 12 different targeted regimes.

CONCLUSION

Breast infections are frequently polymicrobial with a wide variety of organisms isolated, suggesting the need for broad spectrum coverage until culture results become available. Based on our local culture results, the addition of clindamycin to flucloxacillin would provide excellent empiric coverage for all categories of breast infection. An evidence-based treatment guideline is required and should be formulated in close collaboration with microbiology specialists.

Repertoire of human breast and milk microbiota: a systematic review

Breastfeeding is a major determinant of human health. Breast milk is not sterile and ecological large-scale sequencing methods have revealed an unsuspected microbial diversity that plays an important role. However, microbiological analysis at the species level has been neglected while it is a prerequisite before understanding which microbe is associated with symbiosis or dysbiosis, and health or disease. We review the currently known bacterial repertoire from the human breast and milk microbiota using a semiautomated strategy. Total 242 articles from 38 countries, 11,124 women and 15,489 samples were included. Total 820 species were identified mainly composed of Proteobacteria and Firmicutes. We report variations according to the analytical method (culture or molecular method), the anatomical site (breast, colostrum or milk) and the infectious status (healthy control, mastitis, breast abscess, neonatal infection). In addition, we compared it with the other human repertoires. Finally, we discuss its putative origin and role in health and disease.

Breast ultrasound utilization in a safety net emergency department

PURPOSE

The purpose of this study is to (1) assess the diagnostic yield of ultrasounds performed in the emergency department for suspected breast abscess and determine the rates of reimaging, discordance, and emergent intervention in a large, busy safety net hospital and (2) determine clinical factors significantly associated with abscess as a way to improve patient selection for emergent breast ultrasounds.

METHODS

A total of 581 consecutive breast ultrasounds performed in the emergency department for suspected abscess over 15 months were retrospectively reviewed for imaging, demographics, laboratory data, and physical exam findings. Breast abscess was confirmed by combining imaging, clinical, and laboratory data. Linear logistic regression analysis estimated the likelihood of abscess, and the cross-validated area under the receiver operating characteristic curve (AUC) evaluated diagnostic performance.

RESULTS

Final diagnoses included abscess (153/581, 26%), cancer (29/581, 5%), granulomatous mastitis (41/581, 7%), normal (120/581, 21%), and other/indeterminate (238/581, 41%). Factors associated with abscess included induration, fluctuance, erythema, drainage, smoking, diabetes, and Black race. Based on these factors, the AUC of the characteristics predictive of abscess was 0.77 (CI, 0.72-0.81). Six breast cancers were not diagnosed on ultrasound. 40% of ultrasounds (231/581) were considered incomplete/inadequate.

CONCLUSION

74% (428/581) of emergent breast ultrasounds in our population were negative for abscess, while 21% (6/29) of cancers were not diagnosed, and 40% (231/581) of exams were incomplete/inadequate. Patient selection for emergent ultrasounds can be improved, allowing patients with a low likelihood of abscess to be imaged in a more optimal setting.

Best-practice care pathway for improving management of mastitis and breast abscess

BACKGROUND

Surgical subspecialization has resulted in mastitis and breast abscesses being managed with unnecessary admission to hospital, prolonged inpatient stay, variable antibiotic prescribing, incision and drainage rather than percutaneous aspiration, and loss to specialist follow-up. The objective was to evaluate a best-practice algorithm with the aim of improving management of mastitis and breast abscesses across a multisite NHS Trust. The focus was on uniformity of antibiotic prescribing, ultrasound assessment, admission rates, length of hospital stay, intervention by aspiration or incision and drainage, and specialist follow-up.

METHODS

Management was initially evaluated in a retrospective cohort (phase I) and subsequently compared with that in two prospective cohorts after introduction of a breast abscess and mastitis pathway. One prospective cohort was analysed immediately after introduction of the pathway (phase II), and the second was used to assess the sustainability of the quality improvements (phase III). The overall impact of the pathway was assessed by comparing data from phase I with combined data from phases II and III; results from phases II and III were compared to judge sustainability.

RESULTS

Fifty-three patients were included in phase I, 61 in phase II and 80 in phase III. The management pathway and referral pro forma improved compliance with antibiotic guidelines from 34 per cent to 58·2 per cent overall (phases II and III) after implementation (P = 0·003). The improvement was maintained between phases II and III (54 and 61 per cent respectively; P = 0·684). Ultrasound assessment increased from 38 to 77·3 per cent overall (P < 0·001), in a sustained manner (75 and 79 per cent in phases II and III respectively; P = 0·894). Reductions in rates of incision and drainage (from 8 to 0·7 per cent overall; P = 0·007) were maintained (0 per cent in phase II versus 1 per cent in phase III; P = 0·381). Specialist follow-up improved consistently from 43 to 95·7 per cent overall (P < 0·001), 92 per cent in phase II and 99 per cent in phase III (P = 0·120). Rates of hospital admission and median length of stay were not significantly reduced after implementation of the pathway.

CONCLUSION

A standardized approach to mastitis and breast abscess reduced undesirable practice variation, with sustained improvements in process and patient outcomes.

Breast Infection: A Review of Diagnosis and Management Practices

Mastitis is a common condition that predominates during the puerperium. Breast abscesses are less common, however when they do develop, delays in specialist referral may occur due to lack of clear protocols. In secondary care abscesses can be diagnosed by ultrasound scan and in the past the management has been dependent on the receiving surgeon. Management options include aspiration under local anesthetic or more invasive incision and drainage (I&D). Over recent years the availability of bedside/clinic based ultrasound scan has made diagnosis easier and minimally invasive procedures have become the cornerstone of breast abscess management. We review the diagnosis and management of breast infection in the primary and secondary care setting, highlighting the importance of early referral for severe infection/breast abscesses. As a clear guideline on the management of breast infection is lacking, this review provides useful guidance for those who rarely see breast infection to help avoid long-term morbidity.

Breast abscess caused by Staphylococcus aureus in 2 adolescent girls with atopic dermatitis

Atopic dermatitis (AD) is a chronic inflammatory skin disease in children. Patients with AD experience a high rate of colonization of the skin surface by Staphylococcus aureus. Because of a skin barrier defect, there is a potential risk of staphylococcal invasive infection in patients with AD. Here, we present 2 cases of breast abscess caused by S. aureus in 2 adolescent girls with severe AD. Methicillin-sensitive S. aureus was identified from the breast abscess material. They were treated with appropriate antibiotics, however surgical drainage of the abscess was needed in case 1. Identical strains were found from the breast abscess material as well as the lesional and the nonlesional skin of the patients through matrixassisted laser desorption/ionization time-of-flight analysis. We characterized the differential abundance of Firmicutes phylum in patients' skin in microbiota analysis. In particular, S. aureus, a member of Firmicutes, differed significantly between the lesional and the normal-appearing skin. Our cases demonstrate the potential severity of bacterial deep tissue infection in AD and the dysbiosis of skin microbiota may be involved in inflammation in AD.

Predictors of outcomes in managing breast abscesses-A large retrospective single-center analysis

We have retrospectively examined a wide range of clinical characteristics, sonographic features, microbiology, and antibiotic regimens in patients with breast abscesses to seek predictive features related to outcome. Because consensus for optimal treatment of breast abscesses has moved toward minimally invasive management using single or repeated needle aspiration (ASP) coupled with adjuvant antibiotics, we assessed whether any factors correlate with the need for repeat procedures by analyzing the number of ASPs and/or surgical incision and drainage (I&D) per abscess. We examined 127 abscesses in 114 patients from a single urban public hospital, and among clinical characteristics, we found that only smoking history (P = .021) and the presence of nipple rings (P = .005) were associated with greater likelihood of necessitating repeat for abscess resolution procedures. Neither diabetes, lactational status, and HIV nor ultrasound features imaging of an abscess including size >3 cm, multiloculation, rind thickness, or central vs peripheral location were correlated with the need for a repeat procedure. Likewise, no specific micro-organisms predicted a greater likelihood of requiring repeat procedures, and no specific initial antibiotic regimen (gram-positive and/or gram-negative or multiresistance coverage) impacted clinical outcomes. Our data indicate that no specific imaging abscess characteristics, type of micro-organism, or initial choice of antibiotics affect outcomes, and therefore, these features should not preclude attempts at conventional therapy by repeated aspiration and antibiotic treatment. While a smoking history and presence of a nipple ring may increase the risk of a prolonged course, the decision to change antibiotics or repeat aspiration should rely instead on clinical evaluation and judgment by experienced physicians.

Impact on Clinical Management of After-Hours Emergent or Urgent Breast Ultrasonography in Patients with Clinically Suspected Breast Abscesses

Newly diagnosed breast abscesses are generally treated as a medical emergency that may necessitate immediate interventional treatment. At our institution, there is no in-house after-hours coverage for breast ultrasonography. We could find no peer-reviewed studies on the cost-effectiveness or clinical management impact of on-call ultrasound technologist coverage for imaging of breast abscesses. The purposes of this study were to determine the incidence of breast abscess in patients with clinical findings highly suggestive of abscess, identify clinical factors associated with breast abscess in such patients, and determine the impact of after-hours emergent or urgent breast ultrasonography on the clinical management of breast abscesses in both outpatients and inpatients. We retrospectively reviewed 100 after-hours breast ultrasound studies performed at our tertiary care center from 2011 to 2015 for evaluation of a suspected breast abscess. Only 26% of our patients with clinically suspected abscess ultimately had a confirmed abscess. Factors associated with breast abscess were a palpable abnormality and a history of breast surgery within the eight weeks before presentation. After-hours diagnosis of an abscess was associated with after-hours clinical intervention. Of the 74 patients in whom after-hours ultrasound imaging showed no evidence of abscess, only three patients underwent after-hours drainage. Our findings support overnight and weekend breast ultrasound coverage in large tertiary care centers.

Subareolar breast abscess in male patients: a report of two patients with a literature review

Background

Subareolar breast abscess (SBA) is a rare infectious disease of the breast in male patients.

Case presentation

Herein, we report two male patients with SBA. Patient 1 was initially diagnosed with a malignant tumor based on imaging findings; ultrasonography revealed a hypoechoic mass with blood flow. Patient 2 was diagnosed with inflammatory changes to his nipple; ultrasonography findings supported the diagnosis with an irregular hypoechoic mass with blood flow. Both patients received a cytological or histological biopsy preoperatively, which showed an abscess without malignant cells.

Conclusion

These cases serve as an important reminder to consider complete resection of the tumor including the responsible mammary duct (tumor and duct resection (TDR)) for curative therapy of SBA.

Radiologic-Pathologic Correlation for Benign Results After MRI-Guided Breast Biopsy

OBJECTIVE

The majority of MRI-guided breast biopsies yield benign pathology. The purpose of this article is to provide a comprehensive overview of benign pathologic entities commonly encountered at MRI-guided breast biopsy.

CONCLUSION

Proper radiologic-pathologic correlation is an integral component of MRI-guided breast biopsy. Familiarity with the spectrum of MRI findings and key histopathologic features of common benign entities will enhance the radiologist's confidence in determining concordance and lead to improved patient management recommendations.

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

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.

Actinomyces Species Isolated from Breast Infections

Actinomycosis is a chronic infection caused by Actinomyces species characterized by abscess formation, tissue fibrosis, and draining sinuses. The spectrum of infections caused by Actinomyces species ranges from classical invasive actinomycosis to a less invasive form of superficial skin and soft tissue infection. We present a review detailing all Actinomyces species isolated from breast infections in NHS Lothian between 2005 and 2013, Actinomyces species isolated from breast infections referred to the United Kingdom Anaerobe Reference Unit between 1988 and 2014, and cases describing Actinomyces breast infections published in the medical literature since 1994. Actinomyces species are fastidious organisms which can be difficult to identify and are likely to be underascertained as a cause of breast infections. Due to improved diagnostic methods, they are increasingly associated with chronic, recurrent breast infections and may play a more significant role in these infections than has previously been appreciated.

A Review of Inflammatory Processes of the Breast with a Focus on Diagnosis in Core Biopsy Samples

Inflammatory and reactive lesions of the breast are relatively uncommon among benign breast lesions and can be the source of an abnormality on imaging. Such lesions can simulate a malignant process, based on both clinical and radiographic findings, and core biopsy is often performed to rule out malignancy. Furthermore, some inflammatory processes can mimic carcinoma or other malignancy microscopically, and vice versa. Diagnostic difficulty may arise due to the small and fragmented sample of a core biopsy. This review will focus on the pertinent clinical, radiographic, and histopathologic features of the more commonly encountered inflammatory lesions of the breast that can be characterized in a core biopsy sample. These include fat necrosis, mammary duct ectasia, granulomatous lobular mastitis, diabetic mastopathy, and abscess. The microscopic differential diagnoses for these lesions when seen in a core biopsy sample will be discussed.

Clinical experience with aspiration of breast abscesses based on size and etiology at an academic medical center

PURPOSE

Our purpose was to review needle aspiration of breast abscesses and identify factors associated with treatment by aspiration alone versus aspiration with surgical incision and drainage (I/D).

METHODS

This Institutional Review Board-approved, retrospective review of the breast ultrasound database from 2008 to 2010 identified 40 patients (41 abscesses) who underwent aspiration, with or without I/D. Demographics, imaging, number of aspirations, and microbiology were reviewed.

RESULTS

Twenty-two abscesses underwent aspiration only, 16 > 3 cm, 6 ≤ 3 cm (mean 4.3 cm, range 0.9-10 cm). Known risk factors included lactational (11), 3 weeks post partum (1), pregnancy (1), recent biopsy/lumpectomy (5). Nineteen abscesses underwent aspiration and I/D, 15 > 3 cm, 4 ≤ 3 cm (mean 4.1 cm, range 2.2-7.5 cm). Known risk factors included lactational (4), recurrent subareolar abscess (4), diabetes (3), hydradenitis suppuritiva (1), nipple piercing (2), smoking (1), pregnancy (1), HIV (1), and lumpectomy (1). Identified reasons for I/D included lack of improvement/recurrence (12), fistula (3), and one electively after clinical improvement of a recurrent subareolar abscess.

CONCLUSIONS

Abscesses associated with pregnancy and lactation or breast biopsy are effectively managed with aspiration, even when large. Recurrence, chronicity, or fistula may require surgical intervention.

Preventive care and evaluation of the adolescent with a breast mass

Adolescents have little knowledge of preventive breast care or breast screening, yet exposures in youth influence the risk of future breast disease.Nipple piercing increases the risk of trauma and breast infection. Alcohol consumption, smoking, nutrition, obesity, reproductive factors, previous cancer and chest radiotherapy, family history of breast cancer or genetic mutation increase the risk of breast cancer. Breast cancer is rare in adolescents and currently genetic testing is not recommended in those under 18 years, as medical surveillance is not usually recommended until around 25 years. Screening measures include clinical breast exam every 1 to 3 years, and breast self-awareness in healthy women from 20 years; and at least annual breast self examination, with annual clinical breast examination, mammography and magnetic resonance imaging in high-risk patients from 25 years. Breast ultrasound is used in diagnostic evaluation of breast masses in adolescents as mammography is less sensitive in young women.

[Operative risk related to tobacco in gynecology]

If tobacco has been recognized for many years as a major risk factor for cardiovascular, lung diseases and cancer in the general population, women are insufficiently aware of the consequences and the specific gynecological operative risks related to this intoxication. Thus, a regular tobacco consumption increases the risk for many gynecological conditions may require surgical treatment with in addition a significant negative impact on the healing process and the risk of postoperative complications. The operative risk must be explained by surgeons in daily practice gynecological, pelvic surgery or breast screening. The issue of smoking cessation should precede surgery has been established by a consensus conference of experts on perioperative smoking held in 2005. The implementation of these recommendations during the preoperative period requires improvement of staff training and better practices to allow smoking cessation effective and sustainable. It is lawful in this context to delay scheduled surgery of 6 to 8 weeks to allow an optimal smoking cessation and to continue smoking cessation for the time necessary for healing to reduce the excess operative risk associated with smoking.

Echogenic breast masses at US: to biopsy or not to biopsy?

At ultrasonography (US), purely or predominantly echogenic breast masses are rare. These lesions were once assumed to be benign, but recent data suggest that approximately 0.5% of malignant breast lesions appear echogenic. However, correlation with the mammographic appearance, lesion location, and clinical history allows the need for biopsy to be determined. An echogenic mass that is radiolucent at mammography is benign. An echogenic mass that is not radiolucent at mammography may represent a hematoma, complex seroma, silicone granuloma, abscess, galactocele, or fat necrosis when the appropriate clinical history is present. In these cases, biopsy can usually be avoided. If there is a clinical history of cancer or radiation therapy, biopsy is often indicated to assess for metastasis or angiosarcoma. An echogenic mass in an ectatic duct warrants biopsy to exclude carcinoma. An echogenic skin lesion is most likely benign and can occasionally have peripheral vascularity due to surrounding inflammation. However, a skin lesion with internal vascularity is concerning for metastasis or lymphoma. If there is no suspicious clinical history, suspicious sonographic features or mammographic findings would lead to a recommendation for biopsy. Lesions with nonspecific imaging or clinical features (eg, angiolipoma or pseudoangiomatous stromal hyperplasia) may require biopsy to exclude malignancy.

Failure of oral antibiotic therapy, including azithromycin, in the treatment of a recurrent breast abscess caused by Salmonella enterica serotype Paratyphi A

We report a case of recurrent, multifocal Salmonella enterica serotype Paratyphi A breast abscesses, resistant to ciprofloxacin, which relapsed despite surgery, aspiration and multiple courses of antibiotics, including co-trimoxazole and azithromycin. The patient was cured after a prolonged course of intravenous ceftriaxone.

Benign breast disease

This article presents an overview of the benign conditions that affect the breast for the practicing surgeon. The authors discuss the diagnosis and management of a variety of breast pathologic conditions, including those associated with infection and inflammation as well as proliferative and nonproliferative disorders. The authors also offer their experience with the integration of nurse practitioners in the care of patients with benign breast disease.

Body piercing: complications and prevention of health risks

Body and earlobe piercing are common practices in the USA today. Minor complications including infection and bleeding occur frequently and, although rare, major complications have been reported. Healthcare professionals should be cognizant of the medical consequences of body piercing. Complications vary depending on the body-piercing site, materials used, experience of the practitioner, hygiene regimens, and aftercare by the recipient. Localized infections are common. Systemic infections such as viral hepatitis and toxic shock syndrome and distant infections such as endocarditis and brain abscesses have been reported. Other general complications include allergic contact dermatitis (e.g. from nickel or latex), bleeding, scarring and keloid formation, nerve damage, and interference with medical procedures such as intubation and blood/organ donation. Site-specific complications have been reported. Oral piercings may lead to difficulty speaking and eating, excessive salivation, and dental problems. Oral and nasal piercings may be aspirated or become embedded, requiring surgical removal. Piercing tracts in the ear, nipple, and navel are prone to tearing. Galactorrhea may be caused by stimulation from a nipple piercing. Genital piercings may lead to infertility secondary to infection, and obstruction of the urethra secondary to scar formation. In men, priapism and fistula formation may occur. Women who are pregnant or breastfeeding and have a piercing or are considering obtaining one need to be aware of the rare complications that may affect them or their child. Though not a 'complication' per se, many studies have reported body piercing as a marker for high-risk behavior, psychopathologic symptoms, and anti-social personality traits. When it comes to piercing complications, prevention is the key. Body piercers should take a complete medical and social history to identify conditions that may predispose an individual to complications, and candidates should choose a qualified practitioner to perform their piercing. As body piercing continues to be popular, understanding the risks of the procedures as well as the medical and psychosocial implications of wearing piercing jewelry is important for the medical practitioner.

Breast inflammation: clinical examination, aetiological pointers

Red, hot, and painful breast inflammation can have a large number of causes. The history of the condition and clinical observations usually give a pointer to the aetiological diagnosis, which is based on the classic triad of clinical, radiological and histopathological examinations, and guide the choice of additional investigations for rapid therapeutic management of this breast emergency. In breastfeeding women, the cause is often mastitis or, more rarely, an abscess; in non-breastfeeding women, the problem may be mastitis or a periareolar abscess, inflammatory lesions sometimes with secondary infection, or more rarely a real abscess, regardless of a catalogue of various causes. In all cases, the possibility must be considered of inflammatory breast cancer.

Early use of negative pressure therapy in combination with silver dressings in a difficult breast abscess

Combining silver-based dressings with negative pressure therapy after radical excision of chronically infected breast disease is a novel application of two technologies. One patient with complex, chronic, infected breast disease underwent radical excision of the affected area and was treated early with a combination of silver-based dressings and topical negative pressure therapy. The wound was then assessed sequentially using clinical measurements of wound area and depth, pain severity scores and level of exudation. It is possible to combine accepted techniques with modern dressing technologies that result in a positive outcome. In this case, the combination of a silver-based dressing with negative pressure therapy following radical excision proved safe and was well tolerated by the patient. Full epithelisation of the wound was achieved and there was no recurrence of the infection for the duration of the treatment.

Mastitis: comparative etiology and epidemiology

Mastitis is broadly defined as the inflammation of the mammary gland; however, the concept of mastitis is customized to address its social and clinical impact in the case of humans and the health, welfare, and economic consequences for other mammals. There are many microbial, host, and environmental factors that influence the development of mastitis. Some are common to all mammals as well as inherent to each species. Together these factors influence the most prevalent etiological agents for each species and might determine the possibility of interspecies transmission with its consequences to public health. The present review will summarize and compare reports on mastitis etiology and its epidemiology in humans and food animal species.

Breast abscess after nipple piercing: sonographic findings with clinical correlation

The purpose of this series was to review the spectrum of clinical and sonographic features associated with infection after nipple piercing. Between 2002 and 2010, 6 patients presented to our breast center with a breast abscess after nipple piercing. A retrospective analysis of the imaging findings was performed with clinical and pathologic correlation. Patients with breast infections after nipple piercing tend to be young, and the timing since piercing varies from 2 weeks to 17 months. Sonography showed a complex or hypoechoic mass in 5 of 6 patients. Treatment of breast abscesses included surgical incision and drainage, percutaneous drainage, and antibiotic therapy. Surgical evacuation is commonly performed; however, sonographically guided aspiration may be an appropriate management strategy.