Ghahramani L, et al. – Researchers here determined the role of postoperative antibiotics in the prevention of fistula in–ano after incision and drainage of perianal abscess. Findings suggested an important role of postoperative prophylactic antibiotic therapy including ciprofloxacin and metronidazole play in preventing fistula in–ano formation. Considering the complications of fistula in–ano formation and the minor side effects of antibiotic therapy, based on the results, researchers advised a 7–10 course of postoperative antibiotics after incision and drainage of perianal abscess.

Methods

• Authors performed a randomized single blind clinical trial study; they selected 307 patients randomly from those referring for incision and drainage of perianal abscess at Shahid Faghihi Hospital, Shiraz, Iran, during September 2013 to September 2014.
• Random allocation was performed of patients either to receive 7 days of oral metronidazole and ciprofloxacin in addition to their standard care or to only receive standard care without any antibiotics after they were discharged from the hospital.
• They followed the patients for 3 months and evaluated final results.

Results

• In this study, 7 patients were lost to follow-up.
• Significantly lower rates of fistula formation was observed among those who used prophylactic antibiotics (n = 155) compared with those who did not use any medication (n = 144; P < .001).
• Higher rates of fistula formation were observed in men (P = .002).
• Higher rates of fistula development was observed among patients who used more cigarettes (P = .001).
• Univariate analysis indicated that only postoperative antibiotic use had a protective role against fistula formation (odds ratio = 0.426; confidence interval, 0.206–0.881).
• In the regression analysis, postoperative antibiotic use seemed protective against fistula development (odds ratio = 0.371; confidence interval, 0.196–0.703), in addition, male sex presented as a risk factor for developing fistula in-ano (odds ratio = 3.11; confidence interval, 1.31–7.38).