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

INTRODUCTION: Primary breast abscesses occur in <1% of non-lactating women, rising to 11% in women with lactational mastitis. In patients undergoing breast cancer surgery, the inflammatory response to post-operative surgical site infection (SSI) has been implicated in recurrence. Anti-microbial resistance increasingly hampers treatment in each group. AIMS: Describe the demographic and predisposing characteristics of patients with primary breast abscesses and secondary infections, identify the microbial and antimicrobial patterns and formulate an evidence-based protocol for treating breast infections. METHODS: Retrospective cohort study of all breast infections (primary and post-operative) treated at UHL from 2014 to 2017. Data collected from microbiology databases and patient records was analysed using Minitab V18. RESULTS: 537 cultures from 108 patients were analysed. 47 (43.5%) had primary abscesses, 12 (11.1%) were lactational and 49 (45.4%) were post-operative SSI. For primary infections, the mean age was 41.9 (±12.2) and reinfection rate 33%. For SSIs the mean age was 51.8 (±14.52) and reinfection rate 11.8%. Overall, 29.3% were smokers, 6.4% diabetic and 2.9% pregnant. 60 (43%) patients required radiological drainage and 2 (1%) surgical drainage. 57.5% had mixed growth. The most common isolate was Staphylococcus aureus; cultured in 16.7% of primary abscesses and 24% of SSIs. 13 empiric antibiotic regimes were prescribed before 26.4% of patients changed to 12 different targeted regimes. CONCLUSION: Breast infections are frequently polymicrobial with a wide variety of organisms isolated, suggesting the need for broad spectrum coverage until culture results become available. Based on our local culture results, the addition of clindamycin to flucloxacillin would provide excellent empiric coverage for all categories of breast infection. An evidence-based treatment guideline is required and should be formulated in close collaboration with microbiology specialists.

Upper limb lymphedema in breast cancer patients in the era of Z0011, sentinel lymph node biopsy and breast conservation.

INTRODUCTION: Surgical techniques in breast cancer (BCa) have seen a dramatic change recently with breast-conserving surgery (BCS) and sentinel lymph node biopsy (SLNB). The ACOSOG-Z0011 trial reported equivalence in outcomes for certain patients with SLN metastases treated with axillary lymph node dissection (ALND) or SLNB alone. Our aim was to investigate changes in lymphedema referral patterns in BCa patients over the last 3 years in a specialist unit and to elucidate effects of SLNB, BCS, and Z0011 trial publication on such patterns. METHODS: A retrospective study was performed over a 3-year period (May 2012-May 2015). Patients were identified using a prospectively maintained lymphedema database and newly referred BCa patients with data availability were included. RESULTS: Overall lymphedema incidence was 11% (19.2% in ALND and 5.1% in SLNB cohort). There was a statistically significant difference in lymphedema referral patterns after Z0011, new referrals reduced by 20% (chi-sq; p = 0.001). Volume of referrals post ALND was reduced by 40% with concomitant 31% rise in those post SLNB alone, reflecting changing surgical patterns. There was a significant change in extent of lymphnode dissection during ALND (p = 0.003). CONCLUSION: The Z0011 trial in association with wider implementation of SLNB has led to significant changes in the lymphedema referral patterns and extent of ALND.

Chylothorax.

BACKGROUND: Chylothorax is a condition that is debilitating to the point of threatening life. There is controversy over its management, in particular the relative merits of conservative measures and the timing of surgical intervention. METHOD: The literature is reviewed from the basic sciences of chyle composition and flow, to diagnostic approaches, the complications of chyle loss and appropriate management strategies. RESULTS AND CONCLUSION: Prompt diagnosis is essential to institute an effective therapeutic regimen. Surgery achieves fast, safe and effective reversal of this dire situation. Minimally invasive thoracoscopic techniques are gaining wide recognition. Early intervention, which should be aggressive and complete to avoid the immune and nutritional consequences of extended chyle depletion, is recommended.