Abscess Drainage with or Without Antibiotics in Lactational Breast Abscess: Study Protocol for a Randomized Controlled Trial.

Background: Lactational breast abscess, a complication from lactational mastitis, is a common cause of breastfeeding discontinuation. No consensus has been reached regarding the necessity of antibiotics in this disease. The purpose of this trial is to determine if surgical drainage is non-inferior to drainage together with a standard course of antibiotics, in the treatment of lactational breast abscess.

Methods: Breastfeeding females with breast abscess from 18 to 50 years old are eligible for study inclusion. An expected number of 306 patients will be randomly allocated in parallel to the intervention arm (simple drainage without antibiotics) or the control arm (abscess drainage with standard 5-day-course of antibiotics). The primary outcomes include the time to resolution of breast abscess and disease recurrence rate. Secondary outcomes of interests are 3-day-improvement proportion, rate of continuing breastfeeding, treatment failure rate, procedural-related complications, and length of hospital stay. An expected non-inferiority margin for the difference in the primary outcome of interest is set at 1 day, on the basis of a one-sided 97.5% confidence interval.

Discussion: This trial will provide first-hand evidence on whether simple abscess drainage is non-inferior to drainage together with a standard course of antibiotics, in lactational mothers with breast abscess. The indication of antibiotic prophylaxis could be revised if non-inferiority is set up, and guidelines for lactational breast abscess require amendments correspondingly.

Trial Registration: This study has been registered in the Chinese Clinical Trial Registry, and the trial registration number is ChiCTR1900024008.