BACKGROUND
Mastitis is a breast infection that affects as much as a third of breastfeeding women (1), up to 11% of whom develop a complication of lactational breast abscess (2). Non-lactational mastitis and breast abscesses are infrequent (2, 3). Management of mastitis includes alleviation of milk stasis and antibiotics (1, 4). Ultrasound-guided needle aspiration is the recommended method of treatment for breast abscesses (5) with incision and drainage reserved for complicated, large or necrotising abscesses (6).
Despite guideline recommendations, there is evidence to suggest significant variation in practice, particularly concerning antibiotic prescribing, rates of incision and drainage and length of inpatient treatment. At least 40% of women are prescribed inappropriate antibiotics (6, 7) and one in three women are admitted for inpatient treatment (6). However, the rate of incision and drainage is of particular interest as the incidence differs dramatically between studies from 1% (6) to over 85% (8). Inappropriate antibiotic prescribing not only delays treatment but can result in significant infection and hospital admission. Unnecessary operative intervention carries increased risk of cosmetic disfigurement and has significantly higher cost, compared to outpatient ultrasound-guided aspiration. Unnecessary hospital admission is not only wasteful of limited NHS resources but is very disruptive to mother and baby. Considering that the majority breast surgeons are no longer participating in the on-call rota and the acute presentation of primary breast infections, we hypothesise that such variation in practice indeed exists across the UK where patients are treated by the non-specialist general surgeons. However, in order to improve current practice, we need to confirm our hypothesis.
STUDY DESIGN & METHODOLOGY
International trainee collaborative will be established with the assistance of the Mammary Fold Academic and Research Committee and will be the driving force behind this project. The trainee collaborative will be supported by the academic clinicians, MAMMA Steering Committee and methodologists from Imperial College London. All study data will be collected and managed using REDCap electronic data capture tool. This study will be carried out in 3 phases:

- Guidelines and Audit Implementation Network (GAIN). Guidelines on the Treatment, Management & Prevention of Mastitis 2009 [Available from: https://rqia.org.uk/RQIA/files/68/681b5723-6972-4e11-8a09-24cea893d430.pdf.
- Lam E, Chan T, Wiseman SM. Breast abscess: evidence based management recommendations. Expert Rev Anti Infect Ther. 2014;12(7):753-62.
- Trop I, Dugas A, David J, El Khoury M, Boileau JF, Larouche N, et al. Breast abscesses: evidence-based algorithms for diagnosis, management, and follow-up. Radiographics. 2011;31(6):1683-99.
- World Health Organization.Mastitis. Causes and Management Geneva: WHO; 2000 [Available from: https://apps.who.int/iris/bitstream/handle/10665/66230/WHO_FCH_CAH_00.13_eng.pdf?sequence=1.
- Guidelines and Audit Implementation Network (GAIN). Guidelines on the Treatment, Management & Prevention of Mastitis 2009 [Available from: https://rqia.org.uk/RQIA/files/68/681b5723-6972-4e11-8a09-24cea893d430.pdf.
- Patani N, MacAskill F, Eshelby S, Omar A, Kaura A, Contractor K, et al. Best-practice care pathway for improving management of mastitis and breast abscess. Br J Surg. 2018;105(12):1615-22.
- Saboo A, Bennett I. Trends in non-lactation breast abscesses in a tertiary hospital setting. ANZ J Surg. 2018;88(7-8):739-44.
- Barron AU, Luk S, Phelan HA, Williams BH. Do acute-care surgeons follow best practices for breast abscess management? A single-institution analysis of 325 consecutive cases. J Surg Res. 2017;216:169-71.