Delayed Infection of Tissue Expanders in Immediate Two-Stage Implant-Based Breast Reconstruction

Abstract While surgical site infection (SSI) is a major complication of implant-based breast reconstruction, delayed infections remain underrecognized despite their clinical significance. This study aimed to identify the risk factors of delayed infection and compare the clinical outcomes of acute and delayed SSI after tissue expander insertion. Patients who underwent immediate tissue expander-based breast reconstruction between March 2016 and February 2021 were reviewed. Acute SSI (<30 days) and delayed SSI (>60 days) were analyzed and compared with the no-infection group. Among 146 breasts (140 patients), 26 SSIs occurred; 50% (n = 13) were delayed. Multivariable analysis identified wound complication as the sole independent risk factor for delayed SSI. Compared with acute SSI, delayed infection was associated with a significantly longer interval from symptom onset to diagnosis (4.15 vs. 0.33 days, p = 0.0181) and a lower salvage rate (31% vs. 83%), showing borderline significance (p = 0.057). Delayed SSI is not rare after expander-based breast reconstruction. Because salvage is challenging due to diagnostic delay, surgeons and patients should remain vigilant, particularly when risk factors for delayed infection of the tissue expander remain.