Are antibiotics administered in acute appendicitis?

From the Guidelines

Yes, antibiotics are given in appendicitis, with a single preoperative dose of broad-spectrum antibiotics recommended for patients with acute appendicitis undergoing appendectomy, and postoperative antibiotics suggested for patients with complicated acute appendicitis, especially if complete source control has not been achieved. The standard approach involves starting antibiotics as soon as appendicitis is diagnosed, typically before surgery. For uncomplicated appendicitis, common regimens include cefazolin 2g IV every 8 hours or ceftriaxone 1-2g IV daily plus metronidazole 500mg IV every 8 hours. For complicated appendicitis (perforated or gangrenous), broader coverage is needed with piperacillin-tazobactam 3.375g IV every 6 hours or meropenem 1g IV every 8 hours.

Key Considerations

• Antibiotics are typically continued for 24 hours after uncomplicated appendectomy, while complicated cases require 3-5 days of treatment, as recommended by 1 and 1.
• The optimal course of antibiotics remains to be identified, but current evidence suggests that longer postoperative courses do not prevent surgical site infections (SSI) compared with 2 days of antibiotics, as shown in 1.
• Discontinuation of antibiotics after 24 hours seems safe and is associated with shorter length of hospital stay and lower costs, as demonstrated in 1.
• In patients with intra-abdominal infections who had undergone an adequate source control, the outcomes after fixed-duration antibiotic therapy (approximately 3–5 days) are similar to those after a longer course of antibiotics, as stated in 1.

Recommendations

• A single preoperative dose of broad-spectrum antibiotics is recommended for patients with acute appendicitis undergoing appendectomy 1.
• Postoperative antibiotics are suggested for patients with complicated acute appendicitis, especially if complete source control has not been achieved, as recommended by 1 and 1.
• The use of pre-operative broad-spectrum antibiotics in elderly patients undergoing appendectomy for acute appendicitis is strongly recommended, as stated in 1.
• In elderly patients operated on for uncomplicated acute appendicitis, post-operative antibiotics are not recommended, while in those operated for complicated acute appendicitis, post-operative broad-spectrum antibiotics are suggested, as recommended by 1.

From the FDA Drug Label

Piperacillin and Tazobactam for Injection is indicated in adults and pediatric patients (2 months of age and older) for the treatment of appendicitis (complicated by rupture or abscess) and peritonitis caused by beta-lactamase producing isolates of Escherichia coli or the following members of the Bacteroides fragilis group: B. fragilis, B. ovatus, B. thetaiotaomicron, or B. vulgatus.

Yes, antibiotics, such as piperacillin-tazobactam, are given in the treatment of appendicitis, specifically for complicated cases (e.g., rupture or abscess) caused by certain bacteria 2.

From the Research

Antibiotic Use in Appendicitis

• Antibiotics can be used as an alternative to immediate appendectomy in adults with uncomplicated acute appendicitis, with a success rate of around 70% 3, 4.
• The use of broad-spectrum antibiotics, such as piperacillin-tazobactam monotherapy or combination therapy with either cephalosporins or fluoroquinolones with metronidazole, has been shown to be effective in treating uncomplicated acute appendicitis 4.
• However, the use of antibiotics as first-line therapy is not without risks, and patients with high-risk CT findings, such as appendicoliths or a dilated appendix, may be more likely to experience treatment failure 4.

Patient Selection

• Patient selection is crucial when considering antibiotic therapy as an alternative to appendectomy, and factors such as the presence of appendicoliths, mass effect, or a dilated appendix should be taken into account 4.
• Unfit patients without high-risk CT findings may be suitable for an antibiotics-first approach, while those with high-risk CT findings may require surgical management 4.

Duration of Antibiotic Therapy

• The optimal duration of antibiotic therapy for complicated appendicitis is not well defined, but studies suggest that 3-6 days of antibiotic use may be sufficient 5.
• Simplifying the first-line antibacterial regimen for complicated appendicitis in children has been shown to improve adherence to guidelines and reduce the use of antibiotics 6.

Complications and Outcomes

• Antibiotic therapy has been shown to have fewer immediate complications than appendectomy, but may be associated with a higher risk of subsequent failures 3.
• The risk of post-operative complications, such as superficial surgical site infection and deep space infection, can be minimized with appropriate antibiotic use and surgical technique 5.