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

Analysis of risk factors leading to multiple breast abscesses during lactation

We investigated 1805 cases of breast abscesses during lactation to estimate the risk factors for multiple breast abscesses during lactation. A total of 2000 cases of breast abscesses during lactation were investigated using an online questionnaire, and 1805 cases with complete data were analyzed. The survey response rate was 90%. According to the number of abscesses, the patients were divided into 2 groups: single breast abscess (number = 1298) and multiple breast abscess (number = 507). Pearson chi-square test was used to compare the 15 risk factors between the 2 groups. Risk factors with significant differences were substituted into a binary logistic regression model to analyze the independent risk factors associated with multiple breast abscesses during lactation. There were significant differences between the 2 groups in (1) weeks postpartum, (2) separated from the baby, (3) breastfeeding exclusivity, (4) nipple inversion, (5) fever, (6) breast redness/swelling, (7) nipple pain, (8) breast massage by nonmedical staff, with (1), (5), (6), and (8) being independent risk factors. Patients under 6 weeks postpartum, separated from the baby, not exclusively breastfeeding, having an inverted nipple on the affected side, fever, breast skin redness and swelling on the affected side, nipple pain, and having undergone a breast massage by nonmedical staff are more likely to develop multiple breast abscesses.

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.

The cause and effect of gut microbiota in development of inflammatory disorders of the breast

BACKGROUND

Inflammatory disorders of the breast (IDB) damages the interests of women and children and hinders the progress of global health seriously. Several studies had offered clues between gut microbiota (GM) and inflammatory disorders of the breast (IDB). The gut-mammary gland axis also implied a possible contribution of the GM to IDB. However, the causality between them is still elusive.

METHODS

The data of two-sample Mendelian randomization (MR) study related to the composition of GM (n = 18,340) and IDB (n = 177,446) were accessed from openly available genome-wide association studies (GWAS) database. As the major analytical method, inverse variance weighted (IVW) was introduced and several sensitive analytical methods were conducted to verify results.

RESULTS

Inverse variance weighted revealed Eubacterium rectale group (OR = 1.87, 95% CI: 1.02-3.43, p = 4.20E-02), Olsenella (OR = 1.29, 95% CI: 1.02-1.64, p = 3.30E-02), Ruminiclostridium-6 (OR = 1.53, 95% CI: 1.08-2.14, p = 1.60E-02) had an anti-protective effect on IDB. Peptococcus (OR = 0.75, 95% CI: 0.60-0.94, p = 1.30E-02) had a protective effect on IDB. The results were credible through a series of test.

CONCLUSIONS

We revealed causality between IDB and GM taxa, exactly including Ruminiclostridium-6, Eubacterium rectale group, Olsenella and Peptococcus. These genera may become novel biomarkers and supply new viewpoint for probiotic treatment. However, these findings warrant further test owing to the insufficient evidences.

Lactation mastitis: Promising alternative indicators for early diagnosis

Although lactation mastitis (LM) has been extensively researched, the incidence rate of LM remains a salient clinical problem. To reduce this incidence rate and achieve a better prognosis, early and specific quantitative indicators are particularly important. It has been found that milk electrolyte concentrations (chloride, potassium, and sodium) and electrical conductivity (EC) significantly change in the early stages of LM in an animal model. Several studies have evaluated EC for the detection of subclinical mastitis in cows. EC, chloride, and sodium content of milk were more accurate for predicting infection status than were other variables. In the early stages of LM, lactic sodium, chloride, and EC increase, but potassium decreases. However, these indicators have not been reported in the diagnosis of LM in humans. This review summarizes the pathogenesis and the mechanism of LM in terms of milk electrolyte concentration and EC, and aim to provide new ideas for the detection of sub-clinical mastitis in humans.

Risk factors and prognosis of acute lactation mastitis developing into a breast abscess: A retrospective longitudinal study in China

Background

Breast abscess is developed on the basis of acute mastitis, which will cause damage to the physical and mental health of lactating women and is an important factor affecting the rate of breastfeeding. This study examined the risk factors for mastitis to develop into breast abscess, and analyzed the distribution of pathogenic bacteria, bacterial resistance, and treatment outcome.

Methods

The medical records of 316 cases of mastitis and 219 cases of breast abscess were retrospectively collected. We analyzed the bacterial distribution of mastitis and breast abscess, and compared the differences of bacterial drug resistance. Univariate analysis and binary logistic regression were used to analyze the following aspects: age, primiparity or not, history of breast surgery, body temperature, puerperium or not, onset time, located in the nipple/areolar complexe area or not, history of massage by non-professionals, staphylococcus aureus/methicillin-resistant staphylococcus aureus (MRSA) infection or not, diabetes and white blood cell count.

Results

Of the 535 patients, 203 (37.9%) were positive for staphylococcus aureus. There were 133 (65.5%) cases of methicillin-sensitive staphylococcus aureus (MSSA) and 70 (34.5%) cases of MRSA. Concerning bacterial drug resistance, a statistical analysis showed that MSSA had high resistance rate to penicillin (96.2%), ampicillin (91%), clindamycin (42.9%) and erythromycin (45.9%). MRSA had a high resistance rate to penicillin (100%), ampicillin (98.6%), oxacillin (95.7%), erythromycin (81.4%), clindamycin (80%), and amoxicillin (31.7%). Risk factors for progression of mastitis to breast abscess include a body temperature<38.5°C, a postpartum time ≥ 42 days, an onset time ≥ 2 days, lesions in the nipple/areolar complex area, a history of massage by non-medical staff and bacterial cultures for milk or pus that test positive for staphylococcus aureus or MRSA (P < 0.001).

Conclusions

The most common pathogenic bacteria of mastitis and breast abscess is staphylococcus aureus. There are many risk factors for mastitis to develop into breast abscess. We should take effective measures for its risk factors and select sensitive antibiotics according to the results of bacterial culture to reduce the formation of breast abscess.