What are the medical management and surgical indications for acute appendicitis?

From the Guidelines

Medical management of uncomplicated acute appendicitis is a viable alternative to surgery, with a recommended initial intravenous antibiotics regimen followed by oral antibiotics, as outlined in the 2020 update of the WSES Jerusalem guidelines 1. The standard antibiotic regimen consists of intravenous antibiotics for 1-3 days, such as amoxicillin/clavulanate 1.2-2.2 g 6-hourly, ceftriaxone 2 g 24-hourly + metronidazole 500 mg 6-hourly, or ertapenem 1 g 24-hourly, followed by oral antibiotics to complete a 7-10 day course, including options like amoxicillin-clavulanate or ciprofloxacin + metronidazole 1. Some key points to consider in medical management include:

• Close monitoring for clinical improvement within 24-48 hours, including decreasing pain, fever resolution, and normalizing white blood cell count
• Surgery becomes indicated if patients show clinical deterioration, persistent or worsening pain, increasing fever, or signs of perforation
• Surgery is the primary treatment for complicated appendicitis, appendicitis in pregnancy, immunocompromised patients, and those with significant comorbidities
• The success rate of antibiotic therapy ranges from 65-85%, with recurrence rates of 15-30% within one year Laparoscopic appendectomy is recommended as the preferred approach over open appendectomy for both uncomplicated and complicated acute appendicitis, where laparoscopic equipment and expertise are available 1. Some key points to consider in surgical management include:
• Laparoscopic appendectomy offers significant advantages over open appendectomy, including less pain, lower incidence of surgical site infection, decreased length of hospital stay, earlier return to work, and better quality of life scores
• Conventional three-port laparoscopic appendectomy is recommended over single-incision laparoscopic appendectomy due to shorter operative times, less postoperative pain, and lower incidence of wound infection
• Outpatient laparoscopic appendectomy for uncomplicated acute appendicitis is feasible and safe, provided that an ambulatory setting is available 1.

From the FDA Drug Label

1. 1 Intra-abdominal Infections 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.

INTRA‑ABDOMINAL INFECTIONS, including peritonitis, intra‑abdominal abscess, and liver abscess, caused by Bacteroides species including the B. fragilis group (B. fragilis, B. distasonis, B. ovatus, B. thetaiotaomicron, B vulgatus), Clostridium species, Eubacterium species, Peptococcusniger, and Peptostreptococcus species.

The medical management of acute appendicitis includes the use of antibiotics such as piperacillin-tazobactam 2 and metronidazole 3. Surgical indications for acute appendicitis include:

• Complicated appendicitis (e.g. rupture or abscess)
• Peritonitis
• Intra-abdominal abscess Medical management is typically used in conjunction with surgical intervention.

From the Research

Medical Management of Acute Appendicitis

• The medical management of acute appendicitis involves the use of broad-spectrum antibiotics, such as piperacillin-tazobactam monotherapy or combination therapy with either cephalosporins or fluroquinolones with metronidazole 4.
• Approximately 70% of patients with uncomplicated acute appendicitis can be successfully treated with antibiotics 4.
• The risk of recurrence at 1 year with antibiotics-first treatment is around 15.8% (95% confidence interval, 12.05-118.63) 5.
• Recurrence rates of non-operated patients within 1 year are as high as 20-30% 6.

Surgical Indications for Acute Appendicitis

• Laparoscopic appendectomy remains the most common treatment for acute appendicitis 4.
• Surgical management is recommended in patients with CT findings of appendicolith, mass effect, or a dilated appendix who are fit for surgery 4.
• Patients with complicated acute appendicitis should undergo timely surgical intervention 7.
• Certain patient populations, such as pregnant patients and immunosuppressed patients, should undergo timely surgical intervention to decrease the risk of complications 7.
• Interval appendectomy (IA) may be considered in patients with a contained appendiceal perforation on initial presentation, wherein an initial nonoperative approach is preferred 8.

Non-Operative Management of Acute Appendicitis

• Non-operative management (NOM) with antibiotics is a valid treatment option for healthy adults with uncomplicated acute appendicitis 8.
• NOM is also ideal for poor surgical candidates 8.
• Patients presenting with a large appendiceal abscess or phlegmon should undergo percutaneous drainage and antibiotic management 7.
• The decision to delay appendectomy for a few hours on index admission should be made based on the patients' baseline health status and severity of appendicitis 8.