Incidence of and Risk Factors for Lactational Mastitis: A Systematic Review

Imaging enigma in mastitis: A comprehensive study of multifaceted causes, clinical and radiological presentations

BACKGROUND

Mastitis is an inflammatory condition of the breast which represents an array of underlying etiologies encompassing both infectious and non-infectious causes. Exacerbating factors include endemic infections, lack of awareness and suboptimal breastfeeding practices. Neglected cases lead to prolonged morbidity, recurrent episodes, and complications such as abscess or sinus formation, resulting in permanent breast disfigurement. Its overlapping clinical presentation with breast cancer necessitates an integrated multidisciplinary approach for diagnosis and treatment.

OBJECTIVES

The primary aim was to investigate demographic, radiological, and histopathological characteristics of mastitis. Objectives included correlating radiological and histopathological findings, classifying mastitis by etiology, identifying the clinical and imaging patterns across diverse clinical settings to enhance the understanding of mastitis.

MATERIAL AND METHOD

This is a retrospective observational study, analysing the clinical, radiological, and histopathological data from 65 patients with mastitis between February 2023 and February 2024.

RESULTS

The study included 65 patients, aged 18 to 65 years, with breast pain as the most prevalent clinical presentation. Cases were classified as infectious (47.6%) and non-infectious (52%). Acute puerperal mastitis (26.15%) and granulomatous mastitis (30%) were the most common subtypes. The commonest mammographic finding was focal asymmetry. On ultrasound, infectious mastitis showed oedema with other inflammatory changes, including diffuse skin thickening and collections; while non-infectious mastitis typically presented as solitary or multiple breast masses (p < 0.001). Surprisingly, idiopathic granulomatous mastitis constituted the largest percentage amongst various histopathological causes of mastitis in our study.

CONCLUSION

An integrated multidisciplinary approach with understanding of the pathogenesis is imperative for prompt diagnosis and optimizing treatment strategies, thereby improving patient outcome. Radiological imaging is critical for diagnosis, evaluating disease extent, conducting guided interventions, and monitoring treatment response.

Investigating the Anna Karenina principle of the breast microbiome

The relationship between the microbiome and disease has long been a central focus of research in human microbiome. Inspired by Leo Tolstoy's dictum, the Anna Karenina Principle (AKP) offers a framework for understanding the complex dynamics of microbial communities in response to perturbations, suggesting that dysbiotic individuals exhibit greater variability/heterogeneity in their microbiome compared to healthy counterparts. While some studies have proved the alignment of microbiome responses to disease with the AKP effect, it remains uncertain whether the human breast microbiome responds similarly to breast disease. This study used beta-diversity and similarity in Hill numbers, along with shared species analysis (SSA), to explore this issue. We observed that during mastitis, changes in both the taxa richness and composition in the breast milk microbiome align with the AKP effect, while alterations in abundant taxa exhibit an anti-AKP effect. The response of breast tissue microbiome to breast cancer differs from that of milk microbiome to mastitis. Breast cancer induce anti-AKP effects in taxa richness, and non-AKP effects in common taxa and taxa composition. Overall, our findings identified different responses to breast diseases across taxa abundance in the breast microbiome. Mastitis primarily involves increasing the heterogeneity of rare taxa in the breast milk microbiome, while breast cancer associates with decreased dispersion of rare taxa in the tissue microbiome.

Integrating the milk microbiome signatures in mastitis: milk-omics and functional implications

Mammalian milk contains a variety of complex bioactive and nutritional components and microorganisms. These microorganisms have diverse compositions and functional roles that impact host health and disease pathophysiology, especially mastitis. The advent and use of high throughput omics technologies, including metagenomics, metatranscriptomics, metaproteomics, metametabolomics, as well as culturomics in milk microbiome studies suggest strong relationships between host phenotype and milk microbiome signatures in mastitis. While single omics studies have undoubtedly contributed to our current understanding of milk microbiome and mastitis, they often provide limited information, targeting only a single biological viewpoint which is insufficient to provide system-wide information necessary for elucidating the biological footprints and molecular mechanisms driving mastitis and milk microbiome dysbiosis. Therefore, integrating a multi-omics approach in milk microbiome research could generate new knowledge, improve the current understanding of the functional and structural signatures of the milk ecosystem, and provide insights for sustainable mastitis control and microbiome management.

Immunological composition of human milk before and during subclinical and clinical mastitis

Mastitis, an inflammatory condition affecting more than 25% of breastfeeding women, is usually associated with reduced milk secretion, pain, and discomfort, which often leads to early cessation of breastfeeding. Although the etiology of mastitis is multifactorial, a pro-inflammatory state of the mammary gland might be a risk factor. However, changes in milk composition, and specifically in the milk immune profile, prior to and during mastitis have not been well described. To help close this research gap, we documented the immune profiles of milk produced by both breasts of 10 women experiencing clinical (CM) and 8 women experiencing subclinical (SCM) mastitis during the week of sign/symptom development as well as the week prior and compared them with milk produced by 14 healthy controls. CM was defined as having signs/symptoms of mastitis, whereas SCM was presumed if the participant did not have signs/symptoms of CM, but her milk had a somatic cell count >400,000 cell/mL and/or sodium-to-potassium (Na/K) ratio >1.0. Concentration of 36 immune factors (including immunoglobulins, cytokines, chemokines, and growth factors) was quantified via immunoassays. Milk produced by women who developed CM had distinct immune profiles the week prior to diagnosis, particularly elevated concentrations of pro-inflammatory cytokine IL-1β and regulatory cytokines IL-2, IL-4 and IL-10. In contrast, immune profiles in milk produced by women with SCM did not differ from that produced by healthy women or those with CM the week prior to mastitis onset. Once mastitis appeared, marked changes in milk's immune profile were observed in both CM and SCM groups. CM was characterized by elevated concentrations of 27 compounds, including pro-inflammatory cytokines (IL-1β, IL-1ra, and TNFα) and chemokines (including IL-8, eotaxin, IP-10, MCP-1, MIP1α, and MIP1β), compared to healthy controls. Milk's immune profile during SCM was intermediate, showing higher levels of IL-6, IFNγ, and MCP-1 compared to healthy controls, suggesting a milder, more controlled immune response compared to CM. Only milk produced by the mastitis-affected breast had altered immune profiles. Further research is needed to determine if these differences in milk's immune profiles can be used to improve mastitis risk prediction prior to onset of symptoms.

Pre-pregnancy body mass index and lactational mastitis: The Japan Environment and Children's Study

PURPOSE

The association between maternal physique and prevalence of lactational mastitis (LM) in a large study population has not been reported. In this study, we aimed to evaluate the association between pre-pregnancy body mass index (BMI) and LM prevalence.

METHODS

We analyzed data collected from participants enrolled in the Japan Environment and Children's Study, a nationwide birth cohort study conducted between 2011 and 2014. Data from women with singleton births at and after 22 weeks of gestation were analyzed. LM occurrence was identified from medical record transcripts obtained 1-month post-childbirth. Based on the pre-pregnancy BMI, participants were categorized into Group 1 (< 18.5 kg/m2), Group 2 (18.5-24.9 kg/m2), and Group 3 (≥ 25.0 kg/m2). Excluding participants who were not breastfeeding, multivariable logistic regression models were used to evaluate the odds ratios (ORs) for LM in women who were breastfeeding in each BMI category. Group 2 was designated as the reference group. Maternal demographic and socio-economic characteristics were used as confounding factors.

RESULTS

We analyzed 83,170 participants. The adjusted OR for LM in Group 3 was 0.752 (95% confidence interval, 0.606-0.932). The adjusted OR for LM in Group 1 was not significantly changed.

CONCLUSIONS

High pre-pregnancy BMI was associated with decreased LM prevalence compared with that in the reference group. The maternal preconception physique may be associated with LM prevalence.

Comprehensive genetic analysis and predictive evaluation of milk electrical conductivity for subclinical mastitis in Chinese Holstein cows

BACKGROUND

Bovine mastitis significantly impacts the dairy industry, causing economic losses through reduced milk production, lower milk quality, and increased health risks, and early detection is critical for effective treatment. This study analyzed milk electrical conductivity data from 9,846 Chinese Holstein cows over a two-year period, collected during three daily milking sessions, alongside smart collar data and dairy herd improvement test results. The aim was to conduct a comprehensive genetic analysis and assess the potential of milk electrical conductivity as a biomarker for the early detection of bovine subclinical mastitis.

RESULTS

The results revealed significant phenotypic and strong genetic correlations (-0.286 to 0.457) between milk electrical conductivity, somatic cell score, milk yield, activity quantity, and milking speed. Logistic regression models yielded area under the curve values ranging from 0.636 to 0.697 and odds ratio values from 9.70 to 10.69, demonstrating a certain predictive capability of milk electrical conductivity for identifying subclinical mastitis. Various factors influencing milk electrical conductivity, including lactation stage, environmental conditions, age at first calving, parity, and body condition score, were identified. The random regression model demonstrated moderate to high heritability of milk electrical conductivity (0.458 to 0.487), particularly during the early to mid-lactation periods, with all estimates exceeding 0.35 However, after day 275 of lactation, the heritability decreased to below 0.2. Notably, shifts in genetic factors affecting milk components were observed around 60 and 270 days into lactation, with increased environmental sensitivity to milk electrical conductivity during these periods.

CONCLUSIONS

This study demonstrates that milk electrical conductivity is influenced by multiple factors, such as age at first calving, parity, and body condition score, and exhibits significant phenotypic associations with somatic cell score, milk yield, activity quantity, and milking speed. Although milk electrical conductivity showed moderate to high heritability and potential as a predictor for subclinical mastitis, its low genetic correlations with SCS limit its effectiveness as a standalone indicator. Future research should focus on combining EC with other indicators to improve the accuracy of mastitis detection.

Whole-genome sequencing of bacteria accountable for lactational mastitis in humans combined with an examination of their antibiotic resistance profiles

Lactational mastitis, a common condition affecting nursing mothers, is characterized by mammary gland inflammation during lactation. This inflammatory response typically occurs due to bacterial infection. The discomfort and pain associated with lactational mastitis can significantly impact a mother's ability to breastfeed comfortably and may lead to the cessation of breastfeeding altogether if left untreated. Antibiotics are commonly prescribed to target the bacteria causing the infection and alleviate symptoms, aiming to treat the infection. Nevertheless, a notable worry linked to antibiotic use is the emergence of antibiotic resistance, compounded by the possible persistence of antibiotics in milk. Additionally, lactational mastitis is characterized by its polymicrobial nature. In this study, bacteria were isolated from infected breast milk samples and whole-genome sequencing was performed on eleven isolates to accurately identify the bacteria and assess their antibiotic resistance profiles. Using Galaxy tools and the ResFinder database, we identified Bacillus paraanthracis, Bacillus altitudinis, Staphylococcus aureus, Bacillus cereus, Escherichia coli, Alcaligenes faecalis, and Bacillus licheniformis, along with antibiotic-resistant genes like fosB1, cat86, erm (D), blaZ, and mdf (A). ABRicate aided in antimicrobial resistance (AMR) gene analysis, and CARD visualized their distribution. Our study demonstrates that the severity of infection is directly proportional to an increase in somatic cell count (SCC). This research sheds light on microbial diversity in lactational mastitis milk and provides crucial insights into antibiotic-resistance genes. Utilizing bioinformatics tools, such as those employed in this study, can inform the design of effective treatment strategies for lactational mastitis infections.

Sepsis in obstetric care for the emergency clinician: A review

Sepsis remains a leading cause of mortality among pregnant and recently pregnant patients, rendering it a subject of vital importance to emergency clinicians in the US. However, death by sepsis has been found to be largely preventable with prompt and appropriate intervention. This narrative review provides a summary of the physiologic, epidemiologic, and systemic factors specific to obstetric sepsis that contribute to delays in diagnosis and treatment. Additionally, it provides a framework for emergency department providers to approach infection identification, antimicrobial selection, and appropriate resuscitation prior to disposition.

Breastfeeding outcomes at 3 months for women with diabetes in pregnancy: Findings from the Diabetes and Antenatal Milk Expressing randomized controlled trial

BACKGROUND

Women with diabetes in pregnancy have decreased exclusivity and duration of breastfeeding compared with women without diabetes, and their infants are at increased risk of hypoglycemia. Clinicians often suggest pregnant women with diabetes to express breastmilk, and studies have reported increased breastfeeding exclusivity in the early postnatal period for patients who have expressed. Little is known about longer term outcomes. We investigated whether advising low-risk women with diabetes in pregnancy to express beginning at 36 weeks of pregnancy increased exclusivity and maintenance of breastfeeding at 3 months.

METHODS

We conducted a multicenter, two-group, randomized controlled trial at six hospitals in Melbourne, Australia, between 2011 and 2015. Women were randomized to either standard maternity care or advised to hand express for 10 min twice daily, in addition to standard care. Women were telephoned at 12-13 weeks postpartum and asked a series of questions about feeding their baby, perceptions of their milk supply, and other health outcomes.

RESULTS

Of 631 women in the study, data for 570 (90%) were analyzed at 12-13 weeks. After adjustment, we found no evidence that women allocated to antenatal expressing were more likely to be giving only breastmilk (aRR 1.07 [95% CI 0.92-1.22]) or any breastmilk (aRR 0.99 [95% CI 0.92-1.06]) at 12-13 weeks postpartum compared with women in the standard care group.

CONCLUSION

While the practice of antenatal expression for low-risk women with diabetes during pregnancy is promising for increasing exclusivity of breastmilk feeding in hospital, at 12-13 weeks, there was no association with breastfeeding outcomes.

Do inexperienced nurses in the lactation period experience workplace violence? A qualitative study

Introduction

Among clinical healthcare personnel, nurses face the highest proportion of workplace violence, which has a significant impact on their physical and mental well-being as well as their personal and professional lives. However, little is known about the effects of workplace violence on inexperienced breastfeeding nurses and their experiences during and after breastfeeding when they return to work. This study aimed to explore the experiences of inexperienced breastfeeding nurses who encountered workplace violence and its resulting impacts.

Methods

This study employed a descriptive qualitative design. Semi-structured in-depth interviews were conducted with 20 nurses working in various positions and departments at three tertiary hospitals. Purposive and maximum variation sampling techniques were employed. The interview data were analyzed using Colaizzi's method, and the research findings were reported according to Consolidated Criteria for Reporting Qualitative Studies (COREQ)standards.

Results

Inferences regarding workplace violence and risks for inexperienced breastfeeding nurses included physical labor (such as lifting heavy objects and performing cardiopulmonary resuscitation), conflicts, inadequate job skills, role confusion, occupational exposure risks, patient violence, and pressure from older adults. An inductive thematic investigation revealed the "Challenges faced during breastfeeding," "Conflicting professional and family roles," "Out of balance," and "Coping strategies."

Conclusion

Inexperienced breastfeeding nurses experience several negative consequences due to workplace violence. Therefore, it is essential to plan and implement preventive strategies and management programs that specifically target workplace violence among inexperienced breastfeeding nurses.

Trends in clinical management of lactational mastitis among women attending Australian general practice: a national longitudinal study using MedicineInsight, 2011-2022

OBJECTIVE

To examine longitudinal trends in clinical management of lactational mastitis in women attending general practice.

DESIGN

Open cohort study.

SETTING

Australian general practice using data from MedicineInsight.

PARTICIPANTS

Women aged 18 to 44 years with one or more clinical encounters for lactational mastitis between January 2011 and July 2022.

PRIMARY AND SECONDARY OUTCOME MEASURES

The primary outcome measure was the proportion of prescribed oral antibiotics based on the antibiotic type. Secondary outcome measures were the proportion of women prescribed other medications (eg, antifungals, lactation suppressants) or ordered selected clinical investigations including breast ultrasound, blood test, breast milk culture, nipple swab culture or breast aspirate. Outcomes were examined based on the calendar year and individual- or clinical practice-level characteristics.

RESULTS

Among 25 002 women who had one or more clinical encounters related to mastitis, 90.9% were prescribed oral antibiotics. While the proportion of women prescribed an oral antibiotic remained consistent from 2011 to 2022 (91.1% vs 92.5%), there were changes in the proportion receiving prescriptions for di/flucloxacillin (46.1% vs 60.4%) and cefalexin (38.6% vs 26.5%). Fewer than 12% of women were clinically investigated for their mastitis encounter, most commonly a breast ultrasound (7.1%), followed by a selected blood test (3.8%). Requests for breast milk cultures, nipple swab cultures or breast aspirates occurred in less than 1.1% of individuals. Significant increases were evident with respect to ordering of all clinical investigations, with rates at least doubling between 2011 and 2022 (6.6% vs 14.7%). Large variability in clinical management was evident according to both individual- (eg, concessional status) and clinical practice-level characteristics (eg, remoteness).

CONCLUSIONS

Australian general practitioners commonly prescribe oral antibiotics to women with mastitis and largely in line with clinical guidelines. Their use of clinical investigations as part of mastitis management has increased over the last decade.

General practitioners' management of mastitis in breastfeeding women: a mixed method study in Australia

BACKGROUND

Mastitis is a common reason new mothers visit their general practitioner (GP). In Australia, the Therapeutic Guidelines: Antibiotic provides practical advice to GPs managing a range of infections, including mastitis. It is not known if Australian GPs prescribe antibiotics and order investigations as recommended for the management of mastitis.

METHODS

A convergent mixed methods design integrated quantitative analysis of a general practice dataset with analysis of interviews with GPs. Using the large-scale primary care dataset, MedicineInsight, (2021-2022), antibiotics prescribed and investigations ordered for mastitis encounters were extracted. Mastitis encounters were identified by searching 'Encounter reason', 'Test reason' and 'Prescription reason' free text field for the term 'mastitis'; 'granulomatous mastitis' was excluded. Clinical encounters for mastitis occurring within 14 days of a previous mastitis encounter were defined as belonging to the same treatment episode. Semi-structured interviews were conducted with 14 Australian GPs using Zoom or telephone in 2021-2022, and analysed thematically. The Pillar Integration Process was used to develop a joint display table; qualitative codes and themes were matched with the quantitative items to illustrate similarities/contrasts in findings.

RESULTS

During an encounter for mastitis, 3122 (91.7%) women received a prescription for an oral antibiotic; most commonly di/flucloxacillin ([59.4%]) or cefalexin (937 [27.5%]). Investigations recorded ultrasound in 303 (8.9%), blood tests (full blood examination [FBE]: 170 [5.0%]; C-reactive protein [CRP]: 71 [2.1%]; erythrocyte sedimentation rate [ESR]: 34 [1.0%]) and breast milk or nipple swab cultures in approximately 1% of encounters. Analysis using pillar integration showed consistency between quantitative and qualitative data regarding mastitis management. The following themes were identified: - GPs support continued breastfeeding. - Antibiotics are central to GPs' management. - Antibiotics are mostly prescribed according to Therapeutic Guidelines. - Analgesia is a gap in the Therapeutic Guidelines. - Low use of breast milk culture.

CONCLUSIONS

Prescribing antibiotics for mastitis remains central to Australian GPs' management of mastitis. Interview data clarified that GPs were aware that antibiotics might not be needed in all cases of mastitis and that delayed prescribing was not uncommon. Overall, GPs followed principles of antibiotic stewardship, however there is a need to train GPs about when to consider ordering investigations.

Stepwise transvenous lead extraction due to pacemaker pocket infection following lactational mastitis complicated with breast abscess

BACKGROUND

Lactational mastitis is a common painful and debilitating inflammation of breast tissue, generally treated conservatively or with pus puncture in case of breast abscess. However, treating mastitis in patients with implantable surgical material located in the affected breast region can be extremely challenging. We present an unusual case of lactational mastitis complicated by pacemaker pocket infection in a breastfeeding mother.

CASE PRESENTATION

A 35-year-old pacemaker-dependent female developed lactational mastitis seven weeks postpartum. Initially, the condition was treated conservatively with analgesics and antibiotics. After abscess formation, pus was aspirated using fine-needle aspiration technique. Four weeks after mastitis resolution, pacemaker pocket infection developed. According to current cardiovascular implantable electronic device infection treatment guidelines a complete surgical extraction of the entire electronic system, followed by targeted antibiotic treatment and reimplantation of a new device after infection resolution, was recommended. However, after thorough discussion with the young woman and her family and after detailed review of surgery-related risks, she declined a potentially high-risk surgical procedure. Thus, only the pulse generator was explanted; pacing leads positioned in the sub-pectoral pocket; new pacemaker implanted on the contralateral side and broad-spectrum antibiotic therapy continued for six weeks. After breastfeeding cessation, and with chronic fistula development at the primary pacemaker implantation site, the possibility of delayed surgical intervention including complete extraction of retained pacemaker leads was again thoroughly discussed with her. After thoughtful consideration the woman consented to the proposed treatment strategy. A surgical procedure including transvenous lead extraction through the primary implantation venous entry site, using hand-powered bidirectional rotational sheaths, was successfully performed, removing all retained leads through the left subclavian venous entry site, and leaving the fully functional and clinically uninfected pacemaker on the contralateral site intact.

CONCLUSION

Although patients' decisions for delayed extraction in a case of cardiovascular implantable electronic device infection should be discouraged by attending physicians and members of interdisciplinary teams, our case shows that a stepwise treatment strategy may be successful as a bailout clinical scenario in patients with specific requests, demands and / or clinical needs.

Enhanced protein-metabolite correlation analysis: To investigate the association between Staphylococcus aureus mastitis and metabolic immune pathways

Mastitis is a disease characterized by congestion, swelling, and inflammation of the mammary gland and usually caused by infection with pathogenic microorganisms. Furthermore, the development of mastitis is closely linked to the exogenous pathway of the gastrointestinal tract. However, the regulatory mechanisms governing the gut-metabolism-mammary axis remain incompletely understood. The present study revealed alterations in the gut microbiota of mastitis rats characterized by an increased abundance of the Proteobacteria phylum. Plasma analysis revealed significantly higher levels of L-isoleucine and cholic acid along with 7-ketodeoxycholic acid. Mammary tissue showed elevated levels of arachidonic acid metabolites and norlithocholic acid. Proteomic analysis showed increased levels of IFIH1, Tnfaip8l2, IRGM, and IRF5 in mastitis rats, which suggests that mastitis triggers an inflammatory response and immune stress. Follistatin (Fst) and progesterone receptor (Pgr) were significantly downregulated, raising the risk of breast cancer. Extracellular matrix (ECM) receptors and focal adhesion signaling pathways were downregulated, while blood-milk barrier integrity was disrupted. Analysis of protein-metabolic network regulation revealed that necroptosis, protein digestion and absorption, and arachidonic acid metabolism were the principal regulatory pathways involved in the development of mastitis. In short, the onset of mastitis leads to changes in the microbiota and alterations in the metabolic profiles of various biological samples, including colonic contents, plasma, and mammary tissue. Key manifestations include disturbances in bile acid metabolism, amino acid metabolism, and arachidonic acid metabolism. At the same time, the integrity of the blood-milk barrier is compromised while inflammation is promoted, thereby reducing cell adhesion in the mammary glands. These findings contribute to a more comprehensive understanding of the metabolic status of mastitis and provide new insights into its impact on the immune system.

Emergency department use in the postpartum period: a retrospective cohort study

Background

Visits to the emergency room (ED) by women in the postpartum period may reflect gaps in postpartum care and disparities in access to obstetric and primary care services. This study aimed to characterize the patients who visited the ED in the first year after delivery, their reasons for coming to the ED, and the care they received.

Methods

The electronic health record was reviewed for all patients who delivered at University of Iowa Health Care between 2009 and 2023 and visited the ED within 365 days after delivery. Data drawn directly from the EHR included patient demographics and medical history, pregnancy and delivery information, and newborn characteristics. The charts were then reviewed manually for information regarding ED visits including time from delivery, chief complaint, diagnosis, and disposition.

Results

555 pregnancies had ED visits within one year of delivery, with a total 814 ED visits across the study sample. 46.7% of ED visits occurred in the first 30 days following delivery, and 35% of ED visits for obstetric complaints occurred in the first 2 weeks after delivery. Black patients visited the ED more often (mean=1.84 visits, SD=1.30) than white (mean=1.34, SD=0.92, p<0.001) or Hispanic patients (mean=1.35, SD=0.67, p = 0.004). The most common categories of chief complaint were obstetric (34.6%) and gastrointestinal (18.8%), while the most common categories of diagnosis were obstetric (31.8%) and immune/infectious (28.1%).

Conclusions

Visits to the ED are common in the year following delivery. Almost half of these visits occur in the first 30 days after birth. The plurality of postpartum ED visits are due to obstetric complaints, especially in the first few weeks. Black women are more likely to use the ED during this period, potentially due to disparities in healthcare access. These findings suggest that some of these ED visits may be preventable, and that there is room for improvement in post-delivery follow-up, communication between patients and the obstetrics team, and access to outpatient obstetric care.

Body conformation traits in early-lactation associated with clinical mastitis and lameness in lactating Chinese holstein cows

BACKGROUND

Comprehending the correlation between body conformation traits of cows at the early stages of lactation and prevalent lactation diseases might facilitate the execution of selection and feeding strategies that prioritize cow health. This study aimed to evaluate the impact of body conformation traits on the incidence of clinical mastitis and lameness in Chinese Holstein cows. From a pasture herd of 1472 early lactating Chinese Holstein cows, we evaluated 20 body conformation traits. During lactation, this pasture herd was visited weekly to gather clinical mastitis and lameness data. A nine-point scale was used to determine the conformation traits of cows to clarify their linear characters, including frame capacity, rump (RU), feet and leg (FL), mammary system (MS), and dairy character. A longitudinal binary disease (0 = healthy; 1 = diseased) data structure was created by allocating disease records to adjacent official test dates. The impact of body conformation traits on the risk of developing diseases (clinical mastitis and lameness) was analyzed using the logistic regression models.

RESULTS

Compared to cows with low total scores (75-79 points), those with high total scores (80-85 points) of body conformation traits had a significantly lower risk of mastitis (P < 0.001). The disease status (0 or 1: binary variable) of clinical mastitis in lactating cows was significantly impacted negatively by age (P < 0.05). The fore udder attachment (FUA), angularity, rear attachment height (RAH), and rear teat placement (RTP) were all significantly associated with clinical mastitis during lactation (P < 0.05). The rear leg-rear view (RLRV) was significantly correlated with correlated considerably (P < 0.05) with lameness during lactation. An ideal score of four points on the lameness risk dimension of the RLRV may indicate a low risk of lameness. Since the risk of mastitis decreased as this trait score increased, the RTP may be an ideal marker for mastitis risk.

CONCLUSIONS

According to the study, clinical mastitis and lameness risks in cows can be estimated using their body conformation traits. Cows with more centrally located rear teats have a lower risk of mastitis. These results may help dairy farmers identify cows at high risk of disease early in lactation and aid in breeding for disease resistance in cows.

Analysis of relevant factors influencing size of breast abscess cavity during lactation: a cross-sectional study

OBJECTIVE

The aim of this study was to investigate risk factors for the severity of breast abscess during lactation.

METHODS

A cross-sectional study was conducted using data from the Questionnaire survey of breast abscess patients. According to whether the maximum abscess diameter > 5 cm, the patients were divided into two groups for univariate and multivariate regression analysis.

RESULTS

1805 valid questionnaires were included. Univariate and Binary logistic regression analysis demonstrated that low education (OR = 1.5, 95% CI 1.1-2.0, P = 0.005), non-exclusive breastfeeding (OR = 0.7, 95% CI 0.6-0.9, P = 0.004), fever > 37.5 ℃ (OR = 0.7, 95% CI 0.6-0.9, P = 0.003), flat or inverted nipples (OR = 0.7, 95% CI 0.6-0.9, P = 0.005), antibiotic used (OR = 0.7, 95% CI 0.6-0.9, P = 0.006), and non-medical massage (OR = 0.3, 95% CI 0.2-0.4, P < 0.001) were the effective independent influencing factors for the maximum breast abscess diameter > 5 cm.

CONCLUSION

Low education, non-exclusive breastfeeding, fever > 37.5 ℃, inverted or flat nipples, antibiotic used, and non-medical massage history have adverse effects on the severity of breast abscess during lactation.

Body mass index and risk of inflammatory breast disease: a Mendelian randomization study

Introduction

Introduction: in previous studies, obesity was identified as a risk factor for inflammatory breast disease, but its causality is uncertain. In the present study, we performed a two-sample Mendelian randomization (TSMR) analysis to investigate the causal relationship between obesity and inflammatory breast disease. Methods: we use body mass index (BMI) as a measure of obesity. Data for single nucleotide polymorphisms (SNPs) associated with BMI were obtained from UK Biobank. Data for single nucleotide polymorphisms (SNPs) associated with mastitis were obtained from FinnGen Biobank. We used several MR analysis methods, such as inverse-variance weighting (IVW), MR-Egger, weighted median, simple mode and weighted mode to make our results more convincing. We also performed MR-PRESSO test, MR-Egger test, heterogeneity test, pleiotropy test and leave-one-out analysis to make our analysis results more robust and credible. We used odds ratio (OR) to evaluate the causal relationship between BMI and mastitis. Results: based on the IVW random effects model, we found that a one-standard deviation (SD) increase in BMI increased the risk of mastitis by 62.1 % (OR = 1.621, 95 % CI: 1.262-2.083, p = 1.59E-4), which is almost consistent with the results of several other methods. Conclusions: in European individuals, an increase in the number of BMI increases the risk of inflammatory breast disease. People with high BMI need to control their weight to reduce the incidence of inflammatory breast disease.

Neglected medium-term and long-term consequences of labour and childbirth: a systematic analysis of the burden, recommended practices, and a way forward

Over the past three decades, substantial progress has been made in reducing maternal mortality worldwide. However, the historical focus on mortality reduction has been accompanied by comparative neglect of labour and birth complications that can emerge or persist months or years postnatally. This paper addresses these overlooked conditions, arguing that their absence from the global health agenda and national action plans has led to the misconception that they are uncommon or unimportant. The historical limitation of postnatal care services to the 6 weeks after birth is also a contributing factor. We reviewed epidemiological data on medium-term and long-term complications arising from labour and childbirth beyond 6 weeks, along with high-quality clinical guidelines for their prevention, identification, and treatment. We explore the complex interplay of human evolution, maternal physiology, and inherent predispositions that contribute to these complications. We offer actionable recommendations to change the current trajectories of these neglected conditions and help achieve the targets of Sustainable Development Goal 3. This paper is the third in a Series of four papers about maternal health in the perinatal period and beyond.

Breast Imaging and Intervention during Pregnancy and Lactation

Physiologic changes that occur in the breast during pregnancy and lactation create challenges for breast cancer screening and diagnosis. Despite these challenges, imaging evaluation should not be deferred, because delayed diagnosis of pregnancy-associated breast cancer contributes to poor outcomes. Both screening and diagnostic imaging can be safely performed using protocols based on age, breast cancer risk, and whether the patient is pregnant or lactating. US is the preferred initial imaging modality for the evaluation of clinical symptoms in pregnant women, followed by mammography if the US findings are suspicious for malignancy or do not show the cause of the clinical symptom. Breast MRI is not recommended during pregnancy because of the use of intravenous gadolinium-based contrast agents. Diagnostic imaging for lactating women is the same as that for nonpregnant nonlactating individuals, beginning with US for patients younger than 30 years old and mammography followed by US for patients aged 30 years and older. MRI can be performed for high-risk screening and local-regional staging in lactating women. The radiologist may encounter a wide variety of breast abnormalities, some specific to pregnancy and lactation, including normal physiologic changes, benign disorders, and malignant neoplasms. Although most masses encountered are benign, biopsy should be performed if the imaging characteristics are suspicious for cancer or if the finding does not resolve after a short period of clinical follow-up. Knowledge of the expected imaging appearance of physiologic changes and common benign conditions of pregnancy and lactation is critical for differentiating these findings from pregnancy-associated breast cancer. ©RSNA, 2023 Online supplemental material is available for this article. Quiz questions for this article are available through the Online Learning Center.

Predictive Risk Factors for Childbirth-Associated Breast Infections in the United States: A 10-Year Perspective

Infectious mastitis is a common condition that affects up to 33% of lactating women. Several risk factors have been suggested to be strongly associated with breast abscess, nipple infection, and non-purulent mastitis associated with childbirth. In this retrospective cohort study, we gathered data from the National Inpatient Sample (NIS) between 2005 and 2014 and utilized data stratification and backward linear regression to analyze the predictive factors associated with patients hospitalized with breast infection after childbirth, with special consideration of risk factors affecting hospital length of stay (LOS). In the ten-year period, 4614 women were hospitalized with a primary diagnosis of breast abscess, nipple infection, or non-purulent mastitis associated with childbirth. Mean (SD) age was 26.75 (6) years. The highest frequency distribution of cases was observed in patients aged 22-30 years (49.82%). Mean (SD) LOS was 2.83 (1.95) days. Mean (SD) LOS in patients with procedure was 3.53 (2.47) days, which was significantly longer than that in those with no procedure (2.39 (1.36) days, p < 0.001). Primary diagnosis of breast abscess and occurrence of a hospital procedure were most significantly associated with prolonged LOS. Factors such as age, socioeconomic position, severity of functional loss, as well as comorbidities were also contributing risk factors to the development of breast infection and increased hospital LOS. Further studies should examine these findings, as they relate to breastfeeding practices and concentrate on establishing best practices for risk reduction and prevention of childbirth-associated breast and nipple infections and hospitalizations.

Breastfeeding Outcome and Complications in Females With Breast Implants: A Systematic Review and Meta-Analysis

Breast augmentation is a commonly performed cosmetic procedure. We set out to determine whether there was any effect on breastfeeding in females after breast implants. The aim of this study was to perform a systematic review and meta-analysis of the current evidence on breastfeeding outcome and complications in females with breast augmentation. A systematic review was performed utilizing MEDLINE, EMBASE, and all evidence-based medicine reviews from their respective inception dates to November 7, 2022, to assess outcomes of breastfeeding in females with breast implants (PROSPERO ID: CRD42022357909). This review was in accordance with both the Cochrane Handbook for Systematic Review of Interventions and the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Eleven studies (4 prospective and 7 retrospective) in total were included in the review. A total of 8197 out of 9965 (82.25%) patients were successfully able to breastfeed after breast implants. Of 5 studies that included a control group, 343,793 of 388,695 (88.45%) women without breast implants successfully breastfed. A meta-analysis of 5 comparative studies showed a significant reduction of breastfeeding in females with breast implants, n = 393,686, pooled odds ratio = 0.45 (95% CI, 0.38 to 0.53). Complications described included pain, mastitis, insufficient or excessive lactation, and nipple inversion. There may be impairment in ability to breastfeed for females who receive breast implants when compared with those without. Additional studies on the topic are needed to further clarify the relationship.

Risk Factors, Symptoms, and Treatment of Lactational Mastitis

This JAMA Insights Clinical Update reviews the risk factors for and symptoms of lactational mastitis and provides a potential treatment algorithm.

Human Milk Sodium and Potassium as Markers of Mastitis in Mothers of Preterm Infants

Introduction: This prospective longitudinal study examined changes in milk sodium concentration (Na) and sodium:potassium ratio (Na:K), microbiological culture, milk production, and breast health in relation to mastitis after preterm birth. Methods: We studied women who gave birth at 29-34 weeks of gestation in a tertiary obstetric hospital in Perth, Western Australia. Milk samples, 24-hour milk production, and breast health data were collected every second day to day 10 postpartum, then every third day until infant discharge from the neonatal unit. Milk Na and K were measured at point of care (POC) using handheld ion selective meters, and Na:K calculated. Cultures were performed on postnatal days 8, 13, and every 6 days thereafter. For episodes of mastitis, milk was cultured at onset, and Na and Na:K measured daily until resolution. Women were followed up at 4 and 8 weeks postpartum. Results: In a sample of 44 women, 4 mastitis cases were detected in 3 women during their infants' neonatal stay; all had elevated milk Na and Na:K that resolved within 48 hours; 2/4 experienced reduced milk production and 1/4 had heavy growth of Staphylococcus epidermidis. A further 2 mastitis cases were reported in 39 women followed up to 8 weeks postpartum. Four women had elevated milk Na and Na:K without clinical signs of mastitis; three also had reduced milk production. Conclusions: POC testing of milk Na and/or Na:K may offer a useful indicator of breast health. Mastitis may cause an acute reduction in milk production regardless of the presence of culture-positive infection.

Associations Between Mothers' Adverse Childhood Experiences, Material Hardship, and Breastfeeding Challenges in the United States

BACKGROUND

Breastfeeding is the biological norm and is associated with numerous superior health outcomes for children and mothers when compared to human milk substitutes. Yet, breastfeeding difficulties and the inability to meet one's breastfeeding goals are common in the United States and maybe more common among mothers who have experienced trauma.

RESEARCH QUESTIONS

(1) Are mothers' adverse childhood experiences, and current experiences of discrimination, material hardship, and decreased social support associated with breastfeeding challenges; and (2) are these experiences associated with the number of breastfeeding challenges reported?

METHODS

A prospective, non-probability, cross-sectional study design with a diverse sample who had delivered a live baby within the previous year (N = 306) was conducted.

RESULTS

Over 70% of participants reported breastfeeding challenges and 45.2% reported material hardship. Among those who attempted breastfeeding (n = 286), 74.1% had at least one adverse childhood experience; 30.3% had four or more. Logistic and negative binomial regression models determined that adverse childhood experiences, experiences of discrimination, material hardship, and decreased social support were not associated with experiencing any breastfeeding challenges. However, adverse childhood experiences were associated with the number of breastfeeding challenges reported. (The adjusted rate ratio was 1.05; 95% CI [1.00, 1.09], p = .034).

CONCLUSION

We recommend further research on adverse childhood experiences and potential relationships with discrimination, material hardship, and social support to prevent and intervene in cases of breastfeeding challenges to maximize infant, maternal, and public health.

Candida guilliermondii as an agent of postpartum subacute mastitis in Rio de Janeiro, Brazil: Case report

Candida spp. can cause mild-to-severe human infections. Certain species have been described as the etiologic agent of human mastitis, inflammation of the breast tissue. Mastitis affects millions of lactating women and can be a source of disease transmission to the infant. In this work, we report the detection of the unusual etiologic agent of human mastitis, Candida guilliermondii, isolated from the milk of a puerperal woman with subacute mastitis in Rio de Janeiro, Brazil. Species identification was performed by MALDI-TOF MS and genetic sequencing. The patient had a full recovery after antifungal therapy.

The preventive and therapeutic effects of probiotics on mastitis: A systematic review and meta-analysis

Acute mastitis is one of the main reasons why breastfeeding women stop breastfeeding, and medication should be used with caution. Considering the uncertainty of mastitis infection and the indications of antibiotic use, as well as the problem of drug resistance and the safety of medication during lactation, probiotics have become an alternative treatment choice. However, a meta-analysis of the effects of probiotics in preventing and treating lactational mastitis is still lacking. Therefore, we searched six electronic databases and the sites of clinical trial registration, a total of six randomized controlled trials were included in this meta-analysis, which showed that oral probiotics during pregnancy can reduce the incidence of mastitis (RR: 0.49, 95% CI: 0.35 to 0.69; p<0.0001). After oral administration of probiotics, the counts of bacteria in the milk of healthy people and mastitis patients were both significantly reduced (in healthy people: MD: -0.19, 95% CI: -0.23 to -0.16, p<0.00001; in mastitis patients: MD: -0.89, 95% CI: -1.34 to -0.43, p = 0.0001). These indicate that to a certain extent, probiotics are beneficial in reducing the incidence rate of mastitis during lactation and some related mastitis symptoms. However, high-quality multicenter clinical trials are still needed to support this result.

Acute Quadriplegia in a Lactating Woman With Mastitis and Breast Abscess

BACKGROUND

Puerperal mastitis, as well as breast abscess, are common complications that can arise during the breastfeeding period. Acute-onset quadriplegia has been described as a complication of bacterial or viral infections. Here we report a case of puerperal breast abscess with transient acute-onset staphylococcal mediated quadriplegia.

MAIN ISSUE

A 28-year-old lactating Caucasian woman presented at our tertiary perinatal center 31 days postpartum with weakness of all four limbs, the signs and symptoms of mastitis in her left breast and a possible breast abscess with redness, a painful breast lump, and fever. A few hours after admission, the participant developed a proximal quadriplegia.

MANAGEMENT

The participant was admitted to the intensive care unit for monitoring. The neurologists treated her as a possible case of Guillain-Barré syndrome and administered intravenous immunoglobulin therapy for 5 days. The breast abscess was diagnosed via ultrasound and treated by regular aspiration of pus and intravenous antibiotic therapy with ampicillin and sulbactam as Staphylococcus aureus was isolated from breast abscess fluid. Fifteen days after the first symptoms the participant recovered completely and could breastfeed her son exclusively, even though she developed a galactocele on the affected side.

CONCLUSION

We report a possible association between mastitis and abscess formation, common breastfeeding issues, and transient acute onset staphylococcal mediated quadriplegia. To the best of our knowledge this is the only case in the medical literature. Independent of the systemic complications, antibiotic treatment and regular abscess aspirations have proven to be a key strategy to the resolution of puerperal mastitis and breast abscess.

Adaptation of a clinical reasoning model for use in inflammatory conditions of the lactating breast: a retrospective mixed-methods study

Background

Many potential factors associated with Inflammatory Conditions of the Lactating Breast (ICLB) have been reported in the literature, by lactating mothers and clinicians. Clinicians, including general practitioners, lactation consultants and physiotherapists, require a clinical reasoning model that summarises associated or linked factors, to aid in the assessment, treatment, and prevention of ICLB. Thus, we aimed to adapt the existing Breastfeeding Pain Reasoning Model (BPRM), for use in the management of ICLB, using prior research and clinical audit data to guide adaptation. The existing BPRM categorises contributing factors for breastfeeding nipple pain, rather than ICLB.

Methods

Factors linked with ICLB were identified from prior research and considered for inclusion into the existing model. Clinical data from a retrospective audit of ICLB patient notes at a private physiotherapy practice were also examined. Any factors identified from prior research that could not be identified in the clinical notes were not considered for inclusion into the existing model. Additional factors from the clinical notes that appeared repeatedly were considered for inclusion into the adaptation of the BPRM. A draft adapted model was created comprising all eligible factors, considering their counts and percentages as calculated from the clinical data. The research team iteratively examined all factors for appropriate categorisation and modification within the adapted model.

Results

Prior research and data from 160 clinical notes were used to identify factors for inclusion in the adapted model. A total of 57 factors, 13 pre-existing in the BPRM and 44 extra identified from the prior research or clinical audit, comprised the draft adapted model. Factor consolidation and terminology modification resulted in a total of 34 factors in the final proposed adapted ICLB model. The three main categories, CNS modulation, External influences and Local stimulation, from the existing model were maintained, with one minor terminology change to the former Local stimulation category, resulting in 'Local influences' category. Terminology for five subcategories were modified to better reflect the types of factors for ICLB. The most common factors in the adapted model, calculated from the clinical audit population of mothers with ICLB, were employment (85%), high socioeconomic status (81%), antibiotic use during breastfeeding (61%), history of an ICLB (56%), any breast pump use (45%), multiparity (43%), birth interventions (35%), decreased milk transfer (33%), breastfeeding behaviour and practices (33%), nipple pain (30%) and fit and hold (attachment and positioning) difficulty (28%).

Conclusion

An ICLB-specific linked factors model is proposed in this paper. Clinicians treating mothers with ICLB can use this model to identify influencing and determining factors of ICLB clinical presentations and provide targeted education and effective treatment plans.

Staphylococcus epidermidis' Overload During Suckling Impacts the Immune Development in Rats

Mastitis is an inflammation of the mammary gland occurring in 3-33% of the breastfeeding mothers. The majority of mastitis cases have an infectious etiology. More than 75% of infectious mastitis are caused by Staphylococcus epidermidis and Staphylococcus aureus and involves breast milk microbiota alteration, which, may have an impact in lactating infant. The aim of this study was to analyze in rats during the suckling period and later in life the impact of a high and a low overload of Staphylococcus epidermidis, similarly as it occurs during the clinical and the subclinical mastitis, respectively. From days 2 to 21 of life, suckling rats were daily supplemented with low (Ls group) or high (Hs group) dose of S. epidermidis. Body weight and fecal humidity were periodically recorded. On days 21 and 42 of life, morphometry, hematological variables, intestinal gene expression, immunoglobulin (Ig) and cytokine profile and spleen cells' phenotype were measured. Although no differences were found in body weight, Ls and Hs groups showed higher body length and lower fecal humidity. Both doses induced small changes in lymphocytes subpopulations, reduced the plasma levels of Ig and delayed the Th1/Th2 balance causing a bias toward the Th2 response. No changes were found in cytokine concentration. The low dose affected the Tc cells intestinal homing pattern whereas the high dose had an impact on the hematological variables causing leukocytosis and lymphocytosis and also influenced the intestinal barrier maturation. In conclusion, both interventions with Staphylococcus epidermidis overload during suckling, affects the immune system development in short and long term.

Academy of Breastfeeding Medicine Clinical Protocol #36: The Mastitis Spectrum, Revised 2022

A central goal of the Academy of Breastfeeding Medicine is the development of clinical protocols for managing common medical problems that may impact breastfeeding success. These protocols serve only as guidelines for the care of breastfeeding mothers and infants and do not delineate an exclusive course of treatment or serve as standards of medical care. Variations in treatment may be appropriate according to the needs of an individual patient. The Academy of Breastfeeding Medicine recognizes that not all lactating individuals identify as women. Using gender-inclusive language, however, is not possible in all languages and all countries and for all readers. The position of the Academy of Breastfeeding Medicine (https://doi.org/10.1089/bfm.2021.29188.abm) is to interpret clinical protocols within the framework of inclusivity of all breastfeeding, chestfeeding, and human milk-feeding individuals.

Newborn Weight Loss as a Predictor of Persistence of Exclusive Breastfeeding up to 6 Months

Objectives

To investigate the association between neonatal weight loss and persistence of exclusive breastfeeding up to 6 months.

Study Design

An observational cohort study in the setting of a Baby Friendly Hospital, enrolling 1,260 healthy term dyads. Neonatal percentage of weight loss was collected between 48 and 72 h from birth. Using a questionnaire, all mothers were asked on the phone what the infant's mode of feeding at 10 days, 42 days and 6 months (≥183 days) from birth were. The persistence of exclusive breastfeeding up to 6 months and the occurrence of each event that led to the interruption of exclusive breastfeeding were verified through a logistic analysis that included 40 confounders.

Results

Infants with a weight loss ≥7% were exclusively breastfed at 6 months in a significantly lower percentage of cases than infants with a weight loss <7% (95% CI 0.563 to 0.734, p < 0.001). Weight loss ≥7% significantly increases the occurrence of either sporadic integration with formula milk (95% CI 0.589 to 0.836, p < 0.001), complementary feeding (95% CI 0.460 to 0.713, p < 0.001), exclusive formula feeding (95% CI 0.587 to 0.967, p < 0.001) or weaning (95% CI 0.692 to 0.912, p = 0.02) through the first 6 months of life.

Conclusions

With the limitations of a single-center study, a weight loss ≥7% in the first 72 h after birth appears to be a predictor of an early interruption of exclusive breastfeeding before the recommended 6 months in healthy term exclusively breastfed newborns.

Effects of prenatal professional breastfeeding education for the family

Mastering the correct breastfeeding posture remains a challenge for many new mothers. Generalized pregnancy breastfeeding education plays a role in helping mothers master breastfeeding positions and prevent nipple damage. This study prospectively analyzed the effects of prenatal professional breastfeeding education for the family on mastering the lactation latch and preventing nipple damage. Medical records of pregnant women in the authors' hospital from April 2020 to July 2020 were prospectively analyzed. A total of 342 patients were enrolled and divided into experimental and control groups according to whether or not they had received prenatal professional breastfeeding education for the family by the random number table method. The difference in the mastery rate of the postpartum breastfeeding posture and nipple damage was examined three days postpartum. The mastery rate in the experimental group (88.5%) was significantly higher than that in the control group (63.8%), whereas the rate of nipple damage in the experimental group (23.1%) was significantly lower than that in the control group (46.9%). Prenatal professional breastfeeding education for the family can promote mothers' mastery of breastfeeding latch skills and reduce the risk of nipple damage.

Application Value of Health Education Combined with Aerobic Exercise in Nursing of Patients with Mastitis Found in Physical Examination

Objective

To explore the application value of health education combined with aerobic exercise in patients with mastitis found in physical examination.

Methods

The clinical data of 100 patients with mastitis who underwent physical examination in the physical examination center of our hospital from October 2020 to October 2021 were retrospectively analyzed. According to the order of physical examination, they were equally split into experimental group and control group. The control group received the routine clinical intervention, while the experimental group received health education combined with aerobic exercise to evaluate the clinical effects of different intervention modes on patients with mastitis.

Results

Compared with the control group, the experimental group after intervention achieved notably higher scores of CD-RISC, self-management ability, and mastitis-related knowledge (P < 0.001), lower scores of breast pain, skin color, and local mass diameter (P < 0.001), and a higher SF-36 score (P < 0.001).

Conclusion

The clinical intervention combining health education with aerobic exercise in patients with mastitis found in the physical examination is an effective method to improve their mood state and self-management ability, and further research will help provide a good solution for such patients.

Prevalence of and factors associated with lactational mastitis in eastern and southern Africa: an exploratory analysis of community-based household surveys

Background

Lactational mastitis is an extremely painful and distressing inflammation of the breast, which can seriously disrupt breastfeeding. Most of the evidence on the frequency of this condition and its risk factors is from high-income countries. Thus, there is a crucial need for more information on lactational mastitis and its associated factors in Sub-Saharan Africa (SSA).

Methods

We used data from representative, community-based cross-sectional household surveys conducted in 2020 with 3,315 women from four countries (Ethiopia, Kenya, Malawi, and Tanzania) who reported ever-breastfeeding their last child born in the two years before the survey. Our measure of lactational mastitis was self-reported and defined using a combination of breast symptoms (breast redness and swelling) and flu-like symptoms (fever and chills) experienced during the breastfeeding period. We first estimated country-specific and pooled prevalence of self-reported lactational mastitis and examined mastitis-related breastfeeding discontinuation. Additionally, we examined factors associated with reporting mastitis in the pooled sample using bivariate and multivariable logistic regression accounting for clustering at the country level and post-stratification weights.

Results

The prevalence of self-reported lactational mastitis ranged from 3.1% in Ethiopia to 12.0% in Kenya. Close to 17.0% of women who experienced mastitis stopped breastfeeding because of mastitis. The adjusted odds of self-reported lactational mastitis were approximately two-fold higher among women who completed at least some primary school compared to women who had no formal education. Study participants who delivered by caesarean section had 1.46 times higher odds of reporting lactational mastitis than women with a vaginal birth. Despite wide confidence intervals, our models also indicate that young women (15 – 24 years) and women who practiced prelacteal feeding had higher odds of experiencing lactational mastitis than older women (25 + years) and women who did not give prelacteal feed to their newborns.

Conclusions

The prevalence of lactational mastitis in four countries of SSA might be somewhat lower than estimates reported from other settings. Further studies should explore the risk and protective factors for lactational mastitis in SSA contexts and address its negative consequences on breastfeeding.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13006-022-00464-x.

Incidence, antibiotic treatment and outcomes of lactational mastitis: Findings from The Norwegian Mother, Father and Child Cohort Study (MoBa)

BACKGROUND

Mastitis is a common and distressing maternal postpartum condition, but the relationship between mastitis timing and antibiotic treatment and breastfeeding outcomes and postnatal mental health is unclear.

OBJECTIVES

To describe the incidence of mastitis and treatment with antibiotics in first 6 months postpartum, and to investigate the impact of mastitis timing and antibiotic treatment on breastfeeding practices and postnatal mental health.

METHODS

This study is based on 79,985 mother-infant dyads in the Norwegian Mother, Father and Child Cohort Study (MoBa). Women were classified according to self-reported mastitis within first month ('early') or 1-6 months ('later') postpartum and antibiotic treatment. Breastfeeding outcomes included predominant or any breastfeeding and abrupt breastfeeding cessation until 6 months postpartum. Maternal mental health was assessed by self-report at 6 months postpartum.

RESULTS

The incidence of mastitis was 18.8%, with 36.8% reporting treatment with antibiotics. Women reporting early mastitis were less likely to report predominant breastfeeding (adjustedd relative risk [aRR] 0.92, 95% confidence interval [CI] 0.86, 0.99) and any breastfeeding for 6 months (aRR 0.97, 95% CI 0.96, 0.98) than women who did not report mastitis, and more likely to report abrupt breastfeeding cessation (aRR 1.37, 95% CI 1.23, 1.53). Late-onset mastitis was not associated with poorer breastfeeding outcomes. Among women reporting mastitis, the risk of abrupt breastfeeding cessation was higher in those also reporting antibiotic use. Mastitis was associated with an increased risk of mental health problems postpartum which was highest among those reporting no antibiotic use (aRR 1.29, 95% CI 1.18, 1.41), in contrast to those also reporting antibiotic use (aRR 1.08, 95% CI 0.96, 1.22).

CONCLUSIONS

Lactational mastitis and its associated treatment with antibiotics are common. Early (<1 month postpartum) mastitis appears to be a modest risk factor for suboptimal breastfeeding outcomes. In addition, mastitis is associated with poorer mental health.

Breastfeeding Mother and Child Clinical Outcomes After COVID-19 Vaccination

BACKGROUND

Pre-approval clinical trials of the Pfizer/BioNTech messenger RNA COVID-19 vaccine, BNT162b2 did not include participants who were breastfeeding. Therefore, there is limited evidence about outcomes of breastfeeding mother-child dyads and effects on breastfeeding after vaccination.

RESEARCH AIMS

To determine: (1) solicited adverse effects (e.g., axillary lymphadenopathy, mastitis, and breast engorgement), which are unique to lactating individuals; and (2) systemic and local adverse effects of COVID-19 mRNA vaccine on mothers and potential effects on their breastfed infants.

METHOD

This was a prospective cohort study of lactating healthcare workers (N = 88) in Singapore who received two doses of BNT162b2 vaccination (Pfizer/BioNTech). The outcomes of mother-child dyads within 28 days after the second vaccine dose were determined through a participant-completed questionnaire.

RESULTS

Minimal effects related to breastfeeding were reported by this cohort; three of 88 (3.4%) participants had mastitis, one (1.1%) participant experienced breast engorgement, five of 88 (5.7%) participants reported cervical or axillary lymphadenopathy. There was no change in human milk supply after vaccination. The most common side effect was pain/redness/swelling at the injection site, which was experienced by 57 (64.8%) participants. There were no serious adverse events of anaphylaxis or hospital admissions. There were no short-term adverse effects reported in the infants of 67 lactating participants who breastfed within 72 hr after BNT162b2 vaccination.

CONCLUSIONS

BNT162b2 vaccination was well tolerated in lactating participants and was not associated with short-term adverse effects in their breastfed infants.

STUDY PROTOCOL REGISTRATION

The study protocol was registered at clinicaltrials.gov (NCT04802278).

Interactions between human milk oligosaccharides, microbiota and immune factors in milk of women with and without mastitis

Lactational mastitis is an excellent target to study possible interactions between HMOs, immune factors and milk microbiota due to the infectious and inflammatory nature of this condition. In this work, microbiological, immunological and HMO profiles of milk samples from women with (MW) or without (HW) mastitis were compared. Secretor status in women (based on HMO profile) was not associated to mastitis. DFLNH, LNFP II and LSTb concentrations in milk were higher in samples from HW than from MW among Secretor women. Milk from HW was characterized by a low bacterial load (dominated by Staphylococcus epidermidis and streptococci), high prevalence of IL10 and IL13, and low sialylated HMO concentration. In contrast, high levels of staphylococci, streptococci, IFNγ and IL12 characterized milk from MW. A comparison between subacute (SAM) and acute (AM) mastitis cases revealed differences related to the etiological agent (S. epidermidis in SAM; Staphylococcus aureus in AM), milk immunological profile (high content of IL10 and IL13 in SAM and IL2 in AM) and milk HMOs profile (high content of 3FL in SAM and of LNT, LNnT, and LSTc in AM). These results suggest that microbiological, immunological and HMOs profiles of milk are related to mammary health of women.

The efficacy and safety of Chinese massage in the treatment of acute mastitis: A protocol for systematic review and meta-analysis of randomized controlled trials

BACKGROUND

The incidence of acute mastitis (AM) in lactating women has been increasing year by year. If there is no timely and appropriate treatment, AM may develop into mammary abscess and septicemia. This special situation has aroused social attention. Chinese massage has been widely used in the treatment of AM in recent years, but there is no systematic review of the effect of Chinese massage on AM. We plan to explore the efficacy and safety of Chinese massage in the treatment of AM.

METHODS

We will use a computer to search the following 8 electronic databases (PubMed, Web of Science, Cochrane, Embase, Sinomed, China National Knowledge Infrastructure, Chongqing VIP Information, WanFang Data) on November 30, 2021. Randomized controlled trials (RCT) of Chinese massage therapy for AM were screened. Primary outcome measure: overall clinical response rate, breast pain score. Secondary outcome measures: milk secretion, temperature, mass size and time to resolution, White blood cell count, C-reactive protein, and the incidence of adverse reactions. According to the inclusion criteria and exclusion criteria, the included literature will be independently evaluated by two researchers using the RCT bias risk assessment tool in the Cochrane evaluation manual Handbook5.4, and meta-analysis will be performed by RevMan5.4 software. Funnel plots were used to analyze whether the study had publication bias.

RESULTS

We will evaluate the clinical effect of Chinese massage therapy on AM based on RCTs.

CONCLUSION

This study will provide evidence-based evidence for the effectiveness and safety of Chinese massage in the treatment of AM.

PROTOCOL REGISTRATION NUMBER

INPLASY2021120019.

Breast Pumps and Mastitis in Breastfeeding Women: Clarifying the Relationship

Mastitis is a debilitating condition that can impact around 20% of mothers and is characterized by fever, flu-like symptoms and tender, swollen areas of the breasts. Despite the emerging evidence that breast milk dysbiosis is an underlying cause of mastitis, breast pumps have been implicated as a predisposing risk factor in the pathophysiology of mastitis in breastfeeding mothers. Previous studies have suggested that the use of a breast pump increases a mother's risk for developing mastitis, however, incidence rates of mastitis over the stages of lactation do not match breast pump usage rates. Furthermore, breast pumps, even when used at low vacuum, still promote some breast drainage, thus avoiding milk stasis, which is considered a key factor in the development of mastitis. As a consequence, these data suggest that the literature association of breast pumps with mastitis is more a case of reverse causation and not direct association. Moreover, it is important to note that breast pumps are actually a part of the conservative management of mastitis. In combination, these data show that the breast pump should not be considered a driver in the pathophysiology of mastitis in women.

Re-thinking benign inflammation of the lactating breast: Classification, prevention, and management

Despite the known benefits of breastfeeding for both infant and mother, clinical support for problems such as benign inflammation of the lactating breast remain a research frontier. Breast pain associated with inflammation is a common reason for premature weaning. Multiple diagnoses are used for benign inflammatory conditions of the lactating breast which lack agreed or evidence-based aetiology, definitions, and treatment. This article is the second in a three-part series. This second review analyses the heterogeneous research literature concerning benign lactation-related breast inflammation from the perspectives of the mechanobiological model and complexity science, to re-think classification, prevention, and management of lactation-related breast inflammation. Benign lactation-related breast inflammation is a spectrum condition, either localized or generalized. Acute benign lactation-related breast inflammation includes engorgement and the commonly used but poorly defined diagnoses of blocked ducts, phlegmon, mammary candidiasis, subacute mastitis, and mastitis. End-stage (non-malignant) lactation-related breast inflammation presents as the active inflammations of abscess, fistula, and septicaemia, and the inactive condition of a galactocoele. The first preventive or management principle of breast inflammation is avoidance of excessively high intra-alveolar and intra-ductal pressures, which prevents strain and rupture of a critical mass of lactocyte tight junctions. This is achieved by frequent and flexible milk removal. The second preventive or management principle is elimination of the mechanical forces which result in high intra-alveolar pressures. This requires elimination of conflicting vectors of force upon the nipple and breast tissue during milk removal; avoidance of focussed external pressure applied to the breast, including avoidance of lump massage or vibration; and avoidance of other prolonged external pressures upon the breast. Three other key preventive or management principles are discussed. Conservative management is expected to be effective for most, once recommendations to massage or vibrate out lumps, which worsen micro-vascular trauma and inflammation, are ceased.

Re-thinking benign inflammation of the lactating breast: A mechanobiological model

Despite the known benefits of breastfeeding for both infant and mother, clinical support for problems such as inflammation of the lactating breast remains a research frontier. Breast pain associated with inflammation is a common reason for premature weaning. Multiple diagnoses are used for inflammatory conditions of the lactating breast, such as engorgement, blocked ducts, phlegmon, mammary candidiasis, subacute mastitis, mastitis and white spots, which lack agreed or evidence-based aetiology, definitions and treatment. This is the first in a series of three articles which review the research literature concerning benign lactation-related breast inflammation. This article investigates aetiological models. A complex systems perspective is applied to analyse heterogeneous and interdisciplinary evidence elucidating the functional anatomy and physiology of the lactating breast; the mammary immune system, including the human milk microbiome and cellular composition; the effects of mechanical forces during lactation; and the interactions between these. This analysis gives rise to a mechanobiological model of breast inflammation, in which very high intra-alveolar and intra-ductal pressures are hypothesized to strain or rupture the tight junctions between lactocytes and ductal epithelial cells, triggering inflammatory cascades and capillary dilation. Resultant elevation of stromal tension exerts pressure on lactiferous ducts, worsening intraluminal backpressure. Rising leucocyte and epithelial cell counts in the milk and alterations in the milk microbiome are signs that the mammary immune system is recruiting mechanisms to downregulate inflammatory feedback loops. From a complex systems perspective, the key mechanism for the prevention or treatment of breast inflammation is avoidance of excessively high intra-alveolar and intra-ductal pressures, which prevents a critical mass of mechanical strain and rupture of the tight junctions between lactocytes and ductal epithelial cells.

Inflammatory diseases of the breast

Inflammatory disorders of the breast are common benign breast conditions. Lactational mastitis occurs in breastfeeding women and may be associated with breast abscess in severe cases. Non-lactational inflammatory disorders are less common and include idiopathic granulomatous mastitis, periductal mastitis, and tuberculous mastitis. While these disorders have some similarities in their presentation, each disorder requires a specific treatment regimen for resolution, and correct diagnosis is crucial for appropriate treatment. In this chapter, we will review the presentation, diagnosis, and management of each of these distinct clinical entities.

Construct validity and internal consistency of the Breast Inflammatory Symptom Severity Index in lactating mothers with inflammatory breast conditions

Background

Inflammatory Conditions of the Lactating Breast (ICLB) affect more than one in five lactating mothers, yet no fully validated outcome measures exist to aid clinicians in their patient-centred care of women with ICLB. The Breast Inflammatory Symptom Severity Index (BISSI) is an ICLB-specific clinician administered patient-reported outcome measure, currently used by Australian clinicians, who treat mothers with ICLB. To date the BISSI has undergone partial psychometric development. This study, therefore, aimed to undertake the next stage of psychometric development by determining the construct validity and internal consistency of the BISSI.

Methods

A retrospective audit was conducted on patient records of 160 mothers who were treated for ICLB, at a private physiotherapy practice in Melbourne, Australia. An electronic data capture tool was used to collate BISSI scores and associated ICLB assessment variables. Construct validity was determined through factor analysis and discriminant performance. Reliability was determined by assessing measures of internal consistency.

Results

Factor analysis established that BISSI items (n = 10) loaded on to four factors, Wellness, Pain, Physical Characteristics of Affected Area (PCAA), and Inflammation, which together, explained 71.2% of variance. The remaining item (‘Wellness/sickness unspecified’) did not load. Wellness, Pain, PCAA and Inflammation factors individually and collectively displayed the ability to discriminate symptom severity, as scores were significantly higher in mothers with high symptom severity (assessed via AUC close to or >0.7 and P value <0.005 for each factor). The BISSI demonstrated internal consistency with an overall Cronbach alpha of 0.742.

Conclusions

The BISSI has adequate construct validity, demonstrating behaviour consistent with theoretical constructs of inflammation severity, via its dimensionality and ability to discriminate symptom severity. The BISSI also has adequate internal consistency demonstrating reliability. Therefore, clinicians can have confidence that the BISSI is valid, the individual item scores are correlated, and the concepts are consistently measured.

Ligilactobacillus salivarius PS2 Supplementation during Pregnancy and Lactation Prevents Mastitis: A Randomised Controlled Trial

Mastitis is considered one of the main reasons for unwanted breastfeeding cessation. This study aimed to investigate the preventive effect of the probiotic strain Ligilactobacillus salivarius PS2 on the occurrence of mastitis in lactating women. In this multicountry, multicenter, randomized, double-blind, placebo-controlled trial, 328 women were assigned to the probiotic or the placebo group. The intervention started from the 35th week of pregnancy until week 12 post-partum. The primary outcome was the incidence (hazard) rate of mastitis, defined as the presence of at least two of the following symptoms: breast pain, breast erythema, breast engorgement not relieved by breastfeeding, and temperature > 38 °C. The probability of being free of mastitis during the study was higher in the probiotic than in the placebo group (p = 0.022, Kaplan-Meier log rank test) with 9 mastitis cases (6%) vs. 20 mastitis cases (14%), respectively. The hazard ratio of the incidence of mastitis between both study groups was 0.41 (0.190-0.915; p = 0.029), indicating that women in the probiotic group were 58% less likely to experience mastitis. In conclusion, supplementation of L. salivarius PS2 during late pregnancy and early lactation was safe and effective in preventing mastitis, which is one of the main barriers for continuing breastfeeding.

25 Years of Research in Human Lactation: From Discovery to Translation

Researchers have recently called for human lactation research to be conceptualized as a biological framework where maternal and infant factors impacting human milk, in terms of composition, volume and energy content are studied along with relationships to infant growth, development and health. This approach allows for the development of evidence-based interventions that are more likely to support breastfeeding and lactation in pursuit of global breastfeeding goals. Here we summarize the seminal findings of our research programme using a biological systems approach traversing breast anatomy, milk secretion, physiology of milk removal with respect to breastfeeding and expression, milk composition and infant intake, and infant gastric emptying, culminating in the exploration of relationships with infant growth, development of body composition, and health. This approach has allowed the translation of the findings with respect to education, and clinical practice. It also sets a foundation for improved study design for future investigations in human lactation.

Risk factors for lactation mastitis in China: A systematic review and meta-analysis

Background

Lactation mastitis (LM) affects approximately 3% to 33% of postpartum women and the risk factors of LM have been extensively studied. However, some results in the literature reports are still not conclusive due to the complexity of LM etiology and variation in the populations. To provide nationally representative evidence of the well-accepted risk factors for LM in China, this study was aimed to systematically summary the risk factors for LM among Chinese women and to determine the effect size of individual risk factor.

Material and methods

Six major Chinses and English electronic literature databases (PubMed, Web of Science, Chinese Biomedical Literature Database, China National Knowledge Infrastructure, Wan fang Database and China Science Technology Journal Database) were searched from their inception to December 5st, 2020. Two authors extracted data and assessed the quality of included trials, independently. The strength of the association was summarized using the odds ratio (OR) with 95% confidence intervals (CI). The population attributable risk (PAR) percent was calculated for significant risk factors.

Results

Fourteen studies involving 8032 participants were included. A total of 18 potential risk factors were eventually evaluated. Significant risk factors for LM included improper milking method (OR 6.79, 95%CI 3.45–13.34; PAR 59.14%), repeated milk stasis (OR 6.23, 95%CI 4.17–9.30; PAR 49.75%), the first six months postpartum (OR 5.11, 95%CI 2.66–9.82; PAR 65.93%), postpartum rest time less than 3 months (OR 4.71, 95%CI 3.92–5.65; PAR 56.95%), abnormal nipple or crater nipple (OR 3.94, 95%CI 2.34–6.63; PAR 42.05%), breast trauma (OR 3.07, 95%CI 2.17–4.33; PAR 15.98%), improper breastfeeding posture (OR 2.47, 95%CI 2.09–2.92; PAR 26.52%), postpartum prone sleeping position (OR 2.46, 95%CI 1.58–3.84; PAR 17.42%), little or no nipple cleaning (OR 2.05, 95%CI 1.58–2.65; PAR 24.73%), primipara (OR 1.73, 95%CI 1.25–2.41; PAR 32.62%), low education level (OR 1.63, 95%CI 1.09–2.43; PAR 23.29%), cesarean section (OR 1.51, 95%CI 1.26–1.81; PAR 18.61%), breast massage experience of non-medical staff (OR 1.51, 95%CI 1.25–1.82; PAR 15.31%) and postpartum mood disorders (OR 1.47, 95%CI 1.06–2.02; PAR 21.27%).

Conclusions

This review specified several important risk factors for LM in China. In particular, the incidence of LM can be reduced by controlling some of the modifiable risk factors such as improper breastfeeding posture, improper milking method, repeated milk stasis, nipple cleaning, breast massage experience of non-medical staff and postpartum sleeping posture.