Location: usually located in the left lower quadrant (LLQ), due to involvement of the sigmoid colon
Abdominal pain may occur in the suprapubic region: in cases cases with redundant sigmoid colon
Abdominal pain may occur in the right lower quadrant (RLQ): in cases with redundant sigmoid colon or in cases with right-sided cecal diverticulitis (which is more common in Asian populations)
Character
Abdominal pain is usually constant
Abdominal pain is often present for several days prior to presentation
50% of patients have had one or more prior episodes of similar abdominal pain
Chronic Abdominal Pain: approximately 20% of patients with prior acute diverticulitis will develop chronic abdominal pain
May be due to underlying irritable bowel syndrome
May be due to low-grade/smoldering diverticulitis (with persistent diverticular inflammation)
Change in Bowel Habits/Stools
Constipation (see Constipation, [[Constipation]]): present on 50% of cases
Diarrhea (see Diarrhea, [[Diarrhea]]): present in 25-35% of cases
Positive Stool Occult Blood: may be present (although hematochezia is rare)
Urinary Frequency/Urgency/Dysuria (see Dysuria, [[Dysuria]]): occurs in 10-15% of cases (due to bladder irritation from adjacent inflammed sigmoid colon)
Loop of small intestine becomes entrapped in a peri-colonic inflammatory mass
Localized irritation with associated ileus
Colonic Perforation (see Colonic Perforation, [[Colonic Perforation]]): due to rupture of diverticular abscess into peritoneal space
Epidemiology: only 1-2% of acute diverticulitis cases result in colonic perforation with purulent/fecal peritonitis
However, these cases are associated with an approximate 20% mortality rate
Diverticular Abscess
Epidemiology
Abscess occurs in 17% of patients hospitalized with acute diverticulitis
Abscess occurs in 16% of patients with acute diverticulitis without peritonitis
Clinical
May be noted on initial CT scan or may develop precipitously
Abscess should be suspected in patients with uncomplicated diverticulitis without clinical response (in abdominal pain and fever) to 3 days of antibiotics
Fistula
Epidemiology: occurs in 20% of patients with surgically-treated diverticulitis
Mechanism: colonic inflammation -> fistulization between the colon and adjacent viscera (most commonly the bladder)
Clinical
Colovesical Fistula: may result in pneumaturia, fecaluria, dysuria
Colovaginal Fistula: may result in vaginal passage of feces or flatus
Epidemiology: rare (usually associated with perforation and/or peritonitis)
Recurrent Diverticulitis
Recurrence Rates
Recurrence Rate After First Episode of Acute Diverticulitis: 33%
Recurrence Rate After Second Episode of Acute Diverticulitis: 33%
Complication Rates with Recurrent Diverticulitis: recurrent episodes of diverticulitis are not associated with higher incidence of complications than the first episode
Treatment
Antibiotics
General Principles
Coverage: provide coverage for Gram-negative organisms and anerobes
Recovery of More Than One Organism: indicates presence of polymicrobial infection
In which case, anaerobic coverage should be continued (even if no anaerobes are isolated)
First-Choice Antibiotic Regimens
Ampicillin-Sulbactam (Unasyn) (see Ampicillin-Sulbactam, [[Ampicillin-Sulbactam]])
All Patients with Acute Diverticulitis: 20% of patients with require surgical intervention at some point during the course of the disease
Almost all patients who undergo surgical intervention have either had complicated diverticulitis or experienced several recurrent episodes of diverticulitis
Systematic Review of Sigmoid Diverticulitis (2014) [MEDLINE]: in recurrent diverticulitis, the incidence of chronic pain is 5-25% in patients managed operatively vs 20-35% in patients managed non-operatively
Absolute Indications for Surgical Management
Abscess with Failure to Respond to Percutaneous Drainage
Clinical Deterioration or Failure to Improve with Medical Therapy
Enterocutaneous Fistula
Inability to Exclude Colon Cancer
Intractable Symptoms
Bowel Obstruction
Peritonitis
Recurrent Diverticulitis
Relative Indications for Surgical Management
Age <40 y/o
Immunosuppression
Right-Sided Diverticulitis
Symptomatic Stricture
Technique
Laparoscopic Resection: probably best suited for patients with resolved acute diverticulitis and in patients with Hinchey stage I/II disease
Open Resection: may be required
Hinchey’s Classification of Peritoneal Contamination
Stage I: pericolic or mesenteric peritonitis
Stage II: walled-off pelvic abscess
Stage III: generalized purulent peritonitis
Stage IV: generalized fecal peritonitis
Surgical Mortality Rate
Mortality Rate: 1.3-5% (depends on severity of illness and presence of co-morbid conditions)
References
Sigmoid diverticulitis: a systematic review. JAMA. 2014 Jan 15;311(3):287-97. doi: 10.1001/jama.2013.282025 [MEDLINE]
