Enterobacter-Related Deep Sternal Wound Infection After Cardiac Surgery with Delayed Negative-Pressure Wound Therapy Success: A Case Report

Deep sternal wound infection (DSWI) is an uncommon but potentially life-threatening complication after median sternotomy and coronary artery bypass grafting (CABG). Prompt recognition and coordinated surgical-medical management are essential to prevent mediastinal extension, prolonged hospitalization, and reconstructive morbidity.

We report a 70-year-old man with multiple comorbidities (including diabetes mellitus, chronic obstructive pulmonary disease and hypertension) and a history of heavy tobacco exposure. He underwent CABG with an initially uncomplicated postoperative course. Twenty days after discharge, he re-presented with systemic deterioration and severe sternal wound dehiscence with necrotic tissue and clinical sternal instability, consistent with DSWI. Deep-tissue cultures isolated Enterobacter spp, enabling culture-directed antimicrobial therapy. Species-level identification was not available in the archived records, and definitive radiologic confirmation of mediastinitis or sternal osteomyelitis was unavailable. Because of delayed presentation and ongoing wound complexity, negative-pressure wound therapy (NPWT) was initiated as an adjunct strategy. The patient subsequently demonstrated progressive clinical improvement and wound stabilization, without immediate need for flap reconstruction, with plastic surgery input for delayed closure planning.

This case highlights that Gram-negative organisms such as Enterobacter can cause DSWI and supports the importance of deep microbiologic sampling to guide therapy. It also illustrates the use of NPWT as an adjunct following delayed presentation. Although clinical wound stabilization was observed after NPWT initiation, the effectiveness of delayed NPWT cannot be inferred from a single case or limited follow-up.