Table 11 Clinical pathway for patients with acute diverticulitis is illustrated

Clinical signs and symptoms

Diagnosis

 • Abdominal pain in the left lower quadrant of the abdomen without vomiting

 • Elevated temperature

 • Tenderness localized in the left lower quadrant

Laboratory markers

 • Increased white blood cell count

 • Leucocyte shift to left (> 75%)

 • C-reactive protein

Imaging

 • US

 • CT

Uncomplicated acute diverticulitis

Treatment

 • Conservative treatment without antibiotics in patients with CT diagnosis of uncomplicated acute diverticulitis.

 • Antibiotic therapy for 5–7 days in patients with CT diagnosis of uncomplicated acute diverticulitis is reserved for immunocompromised patients and patients with signs of sepsis

Abdominal abscess

 • Antibiotic therapy alone in patients with small diverticular abscesses. Percutaneous drainage combined with antibiotic therapy for 3–5 days in large diverticular abscesses.

 • Whenever percutaneous drainage of the abscess is not feasible or not available, based on the clinical conditions, unless emergency surgery is needed, antibiotics could be considered the primary treatment.

Diffuse peritonitis

 • Primary resection and anastomosis with or without a diverting stoma (in clinically stable patients with no co-morbidities)

 • Hartmann’s procedure (HP) (in critically ill patients and/or in patients with multiple major comorbidities).

 • Laparoscopic peritoneal lavage and drainage in patients with purulent (but not fecal) peritonitis due to complicated diverticulitis. Very controversial.

+

Antibiotic therapy for 4 days

 • A damage control surgical strategy may be useful for patients in physiological extremis from abdominal sepsis

Amoxicillin/clavulanate 2.2 g every 8 h +/− gentamicin 5–7 mg/Kg every 24 h

Antibiotic therapy

Avoid Amoxicillin/clavulanate if local Enterobacteriaceae resistances > 20%.

Piperacillin/tazobactam 6 g/0.75 g LD then 4 g/0.5 g every 6 h or 16 g/2 g by

continuous infusion +/− gentamicin 5–7 mg/Kg every 24 h (in critically ill patients)

Ceftriaxone 2 g every 24 h + metronidazole 500 mg every 8 h

Cefotaxime 2 g every 8 h + metronidazole 500 mg every 8 h

or

In patients with beta-lactam allergy

A fluoroquinolone-based regimen

Ciprofloxacin 400 mg every 8/12 h + metronidazole 500 mg every 8 h

or

An aminoglycoside-based regimen

Amikacin 15–20 mg/kg every 24 h + metronidazole 500 mg every 8 h

or

In patients at high risk for infection with community-acquired ESBL-producing

Enterobacteriaceae

One of the following antibiotics

Tigecycline 100 mg LD, then 50 mg every 12 h (carbapenem-sparing strategy)

Ertapenem 1 g every 24 h

Meropenem 1 g every 8 h (only in patients with septic shock)

Doripenem 500 mg every 8 h (only in patients with septic shock)

Imipenem/cilastatin 500 mg every 6 h (only in patients with septic shock)

In patients at high risk for infection from enterococci including immunocompromised patients or patients with recent antibiotic exposure, consider the use of ampicillin 2 g every 6 h if patients are not being treated with Piperacillin/tazobactam or imipenem/cilastatin (active against ampicillin-susceptible enterococci) or tigecycline.