Abstract: Objective To compare the surgical site infection rate of scar tissue and normal tissue; To determine the difference of leading pathogens colonization and their resistance to common antibiotics between scar tissue and normal tissue. Methods A prospective cohort study was conducted among 129 patients who received plastic and reconstructive surgery and were divided into scar group or non-scar group according to whether scars were involved in their surgery or not. Data on background information, risk factor for bacterial colonization and related confounding factors were collected. The diagnose criteria of SSI was in consistence with the guideline of the Ministry of Health. Microorganism specimen was taken before the surgery. Further identification was undertaken to determine the colonization pattern by antibiotics sensitivity analysis. Multiple Logistic regression analysis was conducted to investigate the association between risk factors and bacterial colonization profile. Results Scar tissue was featured with more surgical site infection (2.3 times, 4.8% vs. 2.1%, P<0.05) and bacterial colonization (1.4 times, 73.2%vs. 53.2%, P<0.05) than normal tissue. Bacterial colonization of scar tissue was significantly connected with factors such as electricity, trauma, chemical injury, site of head and neck. Staphylococcus aureus, as the most common leading pathogen, accounted for 22.4% of all the pathogens and 19.4% of it was found multiple antibiotic resistant. Conclusion Scar tissue is an independent risk factor for surgical site infection with more antibiotic resistant bacteria than normal tissue. Bacterial colonization was significantly related to several etiological factors and anatomic site.

Key words: Scar tissue, Surgical site infection, Bacterial colonization