The susceptibility of sporadic nonpuerperal breast infections: a changing epidemiologic distribution!

Author(s):
Morgan Lane; Jason Sciarretta; John Davis

Background:

Nonpuerperal breast abscesses (NPBA) traditionally isolate aerobic and facultative bacterial cultures however changing biograms have altered therapy. Our study investigates the variation in bacteriology of sporadic nonpuerperal breast infections, compares antibiotic susceptibility, and reviews patient risk factors.

Hypothesis:

We hypothesize that the changing variability in cultured pathogens in nonpuerperal breast infections requires expanded antimicrobial coverage as patients are at risk for inadequate coverage with initiation of empiric antibiotics.

Methods:

Our institutional National Surgical Quality Improvement Project (NSQIP) database was queried during a 4-year period (2015-2018), from which surgical patients completing an incision and drainage of the breast were identified. Data collected included age, gender, race, body mass index (BMI), number of risk factors, location of abscess (central versus peripheral), and culture isolates.

Results:

Eleven patients were identified in the study. The median age was 31 ± 14 years (range, 23- 69) and patients were predominately caucasian (72.7%). Identified risk factors included: smoking tobacco (45.5%), polysubstance abuse (27.3%), diabetes (27.3%) and obesity with a median body mass index (BMI) of 29.4 kg/m2 (range, 22 – 57 kg/m2). One patient had no reported medical history. Incision and drainage was most commonly right sided (63.6%), commonly supra-areolar (54.5%) while the remaining were sub-areolar/inframmmary (45.5%). None of the abscesses recurred on 30 day follow-up. Intraoperative cultures were predominately a single organism (54.5%), most commonly MRSA (66.7%). Mixed anaerobes were identified in four patients (36.4%), including Finegoldi and Prevatella sp. One patient developed Finegoldi magna bacteremia (9%). No deaths occurred in these subset of patients. Two patients failed outpatient oral antibiotic prior to inpatient surgical consultation. Initial antibiotic coverage did not account for adequate anaerobic coverage in four patients (27.3%).

Conclusions:

A small subset of patients with nonpuerperal breast infections demonstrated anaerobic isolates and therefore broader empire antibiotic therapy should be strongly consider in this patient population.