Male urethral stricture is one of the common diseases in urology, with risk factors including a history of hypospadias surgery, indwelling urinary catheterization or instrumental manipulation, trauma, transurethral surgery, and prostate cancer treatment. Its main clinical manifestations are dysuria, weak urinary stream and frequent micturition, which seriously affect patients' quality of life.

Surgery is the main treatment for moderate to severe urethral stricture. Among various surgical procedures, lingual mucosal urethroplasty and end-to-end urethral anastomosis are widely used in clinical practice due to their high long-term patency rates. However, postoperative complications still plague patients. According to reports, the incidence of urinary tract infection within 30 days after surgery ranges from 6.7% to 21%, and the incidence of surgical site infection (SSI) reaches 4.1%. SSI not only impairs surgical efficacy, but also may prolong hospital stay, increase medical costs and even lead to poor prognosis. As defined by the U.S. Centers for Disease Control and Prevention (CDC), SSI refers to surgery-related infections occurring within 30 days after surgery (or up to 1 year if an implant is present), which are specifically classified into three types: superficial incisional SSI, deep incisional SSI, and organ/space SSI. There are significant regional differences in the global incidence of SSI: it is approximately 2.8% in developed countries, while it can be as high as 22.8% in resource-limited regions, indicating an urgent need to optimize perioperative infection prevention and control strategies.

The World Health Organization (WHO) has identified standardized preoperative skin preparation as one of the key measures for preventing SSI. The skin is the main source of bacterial colonization in the surgical area. In particular, the perineum, due to its moist environment, numerous folds and easy accumulation of secretions, is prone to becoming a breeding ground for opportunistic pathogens such as Escherichia coli, Klebsiella pneumoniae, Staphylococcus epidermidis and Enterococcus faecalis-all of which are common pathogenic bacteria causing postoperative infections in male patients with urethral stricture.

Effective preoperative skin cleansing can significantly reduce the local microbial load and the risk of intraoperative contamination, thereby lowering the probability of postoperative infection. Therefore, preoperative skin preparation is not only a routine nursing procedure, but also a crucial component of perioperative infection control. Traditional preoperative skin preparation mostly involves wiping with warm water or normal saline, which can remove surface dirt but lacks sustained antibacterial effects and is difficult to effectively inhibit bacterial regrowth. In recent years, chlorhexidine gluconate (CHG) has gradually become the preferred product for preoperative skin disinfection due to its broad-spectrum antibacterial activity, rapid bactericidal effect and persistent residual action. A number of high-quality studies have confirmed that preoperative showering or local wiping with CHG can significantly reduce the incidence of SSI in orthopedic surgery, cesarean section and implantation of cardiac electronic devices.

However, in the field of urology, especially for complex urethral reconstructive surgeries involving the perineal region (such as lingual mucosal urethroplasty and end-to-end urethral anastomosis), studies on the inhibitory effect of local CHG application on skin bacterial colonization and its clinical value remain scarce. Such surgeries are classified as "clean-contaminated" procedures, characterized by long operative time and extensive tissue exposure. In addition, some surgical techniques require tissue harvesting from the oral cavity, which brings the risk of multiple infection sources and imposes higher requirements for aseptic management of the surgical area. Existing studies mostly take postoperative infection rate as the endpoint indicator, and few focus on the impact of preoperative interventions on the dynamic changes of skin microorganisms. Quantitative detection of colony-forming units (CFU) and bacterial species distribution in key anatomical sites can more objectively evaluate the immediate and sustained bacteriostatic effects of different skin preparation methods, thereby revealing their underlying mechanisms of action.

Therefore, this study intends to conduct a prospective research to compare the bacteriostatic effects of different preoperative skin preparation methods in the target population, so as to provide clinical practice with more evidence-based guidelines for perioperative skin preparation procedures.

Inclusion Criteria:

Male patients aged ≥18 years with a clinically confirmed diagnosis of urethral stricture, who are scheduled to undergo lingual mucosal urethroplasty or end-to-end urethral anastomosis.

Possess normal cognitive and communication abilities, and be able to cooperate with preoperative cleaning procedures and postoperative follow-up.

No history of topical antimicrobial therapy on the perineal region before surgery, and no systemic antibiotic administration within 1 week prior to surgery.

Voluntarily participate in this study and sign the informed consent form.

Exclusion Criteria:

Complicated with severe systemic infectious diseases, or suffering from immunodeficiency diseases (e.g., AIDS, long-term use of immunosuppressants).

Presence of skin damage, ulcers, eczema or other dermatoses on the perineal skin, which may interfere with cleaning procedures and bacterial sample collection.

A definite history of allergy to chlorhexidine gluconate (CHG) or study-related supplies.

Having surgical contraindications such as severe hepatic and renal insufficiency, or coagulation dysfunction.

Inability to cooperate with preoperative cleaning procedures, or failure to complete postoperative follow-up due to personal reasons