Single-dose metronidazole vs 5-day multi-drug antibiotic regimen in excision of pilonidal sinuses with primary closure: a prospective, randomized, double-blinded pilot study.

AIM: To compare infection-related wound complications following excision of pilonidal sinuses with primary closure using either single-dose intravenous (i.v.) administration of metronidazole preoperatively or a broad-spectrum multi-drug regimen. PATIENTS AND METHODS: This is a double-blinded study wherein 50 patients were randomized into receiving either single-drug (metronidazole 500 mg i.v.) prophylaxis preoperatively or multi-drug cover (cefuroxime 1.5 g i.v. and metronidazole 0.5 g i.v. preoperatively, and co-amoxiclav 375 mg orally 8-hourly postoperatively for 5 days). They were reviewed at 1, 2 and 4 weeks postoperatively. Wounds were graded as follows: I, healthy; II, redness and swelling of edges; III, abscess in relation to a suture; IV, spreading wound infection; and V, wound breakdown. Other factors considered were the distance from the lowest wound margin to the anal verge and previous local surgery.
RESULTS: Fifty patients (38 men and 12 women, mean age 27 years) underwent pilonidal sinus surgery. At week 1, there was no difference in wound infection rates (p=0.9). However, there were significantly more wound infections in the single-drug group at week 2 (p<0.0001) and week 4 (p=0.03). Seventy-two per cent of all patients had complete wound healing at week 4. Distance from the anal verge and previous surgery did not affect wound infection rates (p> or =0.2). Treating such complications costs 73,219.20 dollars per 100 patients.
CONCLUSION: A broad-spectrum 5-day regimen is superior to 'single-shot' antibiotic prophylaxis in preventing infection-related wound complications. However, this study needs to be conducted in a larger number of patients to have statistical power.

RCT Entities:   Population Interventions Outcomes