Definition
A.Diverticulum is the saclike protrusion of mucosa through the muscular colonic wall. Protrusions occur in weakened areas of the bowel wall. Diverticulosis is the presence of diverticula within the colon, but it does not imply a pathologic condition, and may remain asymptomatic. Diverticulitis occurs when the diverticula become plugged and inflamed. Diverticular bleeding occurs due to injury of the blood vessel within the diverticulum and subsequent rupture into the lumen. Diverticular disease occurs over a continuum including simple asymptomatic diverticular disease, uncomplicated symptomatic diverticulitis, and complicated symptomatic diverticulitis. Complicated diverticulitis includes problems arising from abscess, perforation, fistula, peritonitis, and sepsis.
B.An increased risk of developing diverticular disease is associated with a diet that is high in red meat and total fat content. This risk can be reduced by a diet high in fiber content, especially with fruits and vegetables (cellulose; see Table B.7).
C.Diverticulosis is often diagnosed as an incidental finding on a barium enema (BE) or sigmoid/colonoscopy.
D.Recurrent attacks of diverticulitis can result in the formation of scar tissue, leading to narrowing and obstruction of the colonic lumen.
Incidence
Diverticulosis is very common and increases with age:
A.Prevalence by age:
1.20% by age 40.
2.60% by age 60.
B.No significant difference in prevalence by gender. Male preponderance in diverticular patients less than 50 years old and female preponderance in patients greater than age 70.
C.Diverticulosis becomes symptomatic in 70% of cases. It leads to diverticulitis in 5% to 25% and is associated with bleeding in 5% to 15%. The sigmoid colon is commonly affected in Western countries whereas right sided involvement is more commonly seen among Asian entities.
D.Diverticulitis can be separated into two groups:
1.Simple, with no complications; responds to treatment such as dietary changes without the need for surgery.
2.Complicated, with abscesses, fistula, obstruction, perforation, and peritonitis leading to sepsis; usually requires surgery.
Pathogenesis
A.The formation of diverticula is multifactorial. Patients with diverticula have been shown to have higher colonic segmental pressures, which cause the mucosa to herniate through the colonic wall. The increased pressure might be due to upregulation of smooth muscle receptors, and combined with production of abnormal collagen, luminal narrowing, abnormal elastin deposits within the colonic wall, lead to the development of the herniation. Diverticulitis occurs due to micro- or macroperforation of the diverticular wall, which is a result of persistent increased pressure and retained food particles that erode the wall. The perforation is followed by inflammation and localized necrosis. Diverticular bleeding occurs when the blood vessel contained within the diverticulum becomes weakened due to structural repositioning and ruptures into the colon lumen.
Predisposing Factors
A.Advanced age.
B.Obesity (84%–96%).
C.Dietary factors:
1.Low residue.
2.High red meat and total fat content.
D.Complicated diverticular disease is increased in the following:
1.Smokers.
2.Chronic nonsteroidal anti-inflammatory drugs (NSAIDs) use.
3.Acetaminophen use (especially paracetamol).
E.Physical inactivity.
F.Indication that genetics are a predisposing factor:
1.Left-sided diverticula is predominant in the United States.
2.Right-sided (cecal) diverticula is predominant in Asia.
Common Complaints
A.Diverticulosis is usually asymptomatic.
B.Painless rectal bleeding is the hallmark of diverticular bleeding, with intermittent passage of maroon or bright red blood.
C.Common diverticulitis symptoms:
1.Left lower quadrant (LLQ). pain.
2.Constipation.
Other Signs and Symptoms
A.Back pain.
B.Flatulence.
C.Periodic abdominal distension.
D.Borborygmi, or loud, prolonged gurgles caused by hyperactive intestinal peristalsis.
E.Diarrhea.
F.Nausea or vomiting.
G.Dysuria.
H.Tenderness on palpation, possible guarding.
I.Low-grade fever.
Subjective Data
A.Review onset, duration, and course of symptoms, including size, color, consistency, and frequency of stools.
B.Ask the patient if constipation is a chronic or acute problem, and if it alternates with diarrhea.
C.Review the patient’s daily diet and fluid intake.
D.Ask the patient about medication use, including iron supplements, NSAIDs, and acetaminophen.
E.Inquire about the color, amount, and frequency of rectal bleeding. Does the patient strain when having a bowel movement (BM)?
F.Review the patient’s history of pain with defecation.
Physical Examination
A.Check temperature, pulse, respirations, blood pressure (BP), and weight.
B.The physical examination may be relatively unremarkable but most commonly reveals abdominal tenderness or a mass.
C.Inspection:
1.Observe the general overall appearance for signs of pain.
2.Inspect the abdomen in detail, assessing for distension.
D.Auscultate the abdomen. Absent bowel sounds suggest peritoneal inflammation.
E.Percuss the abdomen.
F.Palpate:
1.Palpate the abdomen for rebound tenderness or masses signaling possible abscess and tenderness.
2.Palpate beneath right costal arch, checking for Murphy’s sign or pain on deep inspiration.
G.Rectal exam: Evaluate for hemorrhoids, masses, fissures, fistulas, inflammation, and stool in ampulla.
Diagnostic Tests
A.Labs:
1.Complete blood count (CBC)—leukocytosis supports the diagnosis of diverticulitis.
2.Comprehensive metabolic profile (CMP)—evaluate kidney function, liver enzymes, and electrolytes.
3.Urinalysis—sterile pyuria may occur.
4.Stool studies are only indicated for patients with diarrhea and are rarely indicated.
5.Human chorionic gonadotropin (HCG) in all females of childbearing age.
6.C-reactive protein (CRP) to assess for inflammation.
7.Stool hemoccult or fecal immunoassay.
B.Imaging:
1.CT contrasted of the abdomen and pelvis.
2.Ultrasonography—can show bowel wall thickening, abscess (with/without gas bubbles).
3.MRI—acceptable to avoid radiation.
4.Abdominal radiography—shows abnormality in 30% to 50% of symptomatic patients.
5.BE after infection subsides. Caution: A BE during the acute phase may increase intraluminal pressure and cause bowel perforation.
C.Endoscopy:
1.Colonoscopy.
2.Proctosigmoidoscopy.
Differential Diagnoses
A.Diverticulitis.
B.Diverticulosis.
C.Acute appendicitis.
D.Bowel obstruction.
E.Ischemic colitis.
F.Colon cancer.
G.Hemorrhoids.
H.Constipation or impaction.
I.Inflammatory bowel disease (IBD).
J.Urologic disorder: Pyelonephritis.
K.Pelvic inflammatory disease (PID).
L.Ectopic pregnancy.
Plan
A.Patients who have evidence of complicated diverticulitis (with perforation, fistula, obstruction, or abscess) need to be admitted to hospital and treated as inpatients. All inpatients are treated with intravenous (IV) fluid support, IV antibiotics, and pain control. Depending on the complication, other interventions may be undertaken by a specialist.
B.Patients who have uncomplicated diverticulitis but one of the following also should be treated as inpatients: microperforation, fever over 102.5°F, significant leukocytosis, severe pain, inability to tolerate oral intake, immunosuppression, significant comorbidities, poor support system, or outpatient treatment failure.
C.Patients with uncomplicated diverticulitis and none of the earlier characteristics may be treated as outpatients.
D.Antibiotic therapy should be continued for 7 to 10 days. Choices include the following:
1.Cipro 500 mg q12h + Metronidazole 500 mg q8h.
2.Bactrim DS one tablet every 12 hours + metronidazole 500 mg every 8 hours.
3.Augmentin 875 mg every 12 hours.
4.Moxifloxacin 400 mg daily if beta-lactam and/or metronidazole not tolerated.
Check local resistance patterns. If resistance is greater than 10% to one agent, choose alternative regimen.
E.Outpatient diet. No evidence to support dietary restrictions during acute episode of diverticulitis.
F.Long-term dietary management:
1.High-fiber diet, including bran, beans, fruits, and vegetables.
2.Bulk agents if unable to tolerate bran.
3.There is no evidence to support the avoidance of foods such as corn, seeds, or nuts.
G.Relapse: Approximately one-third of patients with an initial episode of diverticulitis will experience a second episode and one-third of those patients will progress to have a third recurrence. Whereas surgical management used to be considered based on the number of episodes of diverticulitis, currently surgical management is not dependent on the number of uncomplicated episodes but rather the presence of a complicating problem. Furthermore, there is no evidence to support the idea that uncomplicated episodes progress or worsen over time.
Follow-Up
A.Outpatients should be reevaluated after 3 days of therapy and every week until resolution of symptoms. Generally reimaging is not indicated or recommended.
B.A colonoscopy should be performed from 6 weeks after recovery to evaluate the extent of the diverticulosis/rule out other manifestations such as colon cancer.
Emergent Issues/Instructions
Arrange for prompt hospitalization and surgical consultation if the patient’s temperature rises above 102.5°F, the patient’s pain worsens, peritoneal signs develop, or white blood cell (WBC) continues to rise. Surgery consultation is required for abscess, peritonitis, obstruction, fistula, or failure to improve after several days of medical management.
Consultation/Referral
A.Consult a physician if the patient has mild diverticulitis: temperature less than 101°F; WBC less than 13,000 to 15,000.
Individual Considerations
A.Geriatrics:
1.For the older adult with existing diverticulosis, nurse practitioner (NPs) should practice special consideration of the following geriatric syndromes:
a.Pain—poorly relieved pain is an important cause of functional impairment at any age group:
i.Elderly patients have a diminished sensorium, allowing pathology to advance to a dangerous point prior to symptom development.
ii.Elderly with abdominal pain may present with altered mental status. Cognitive impairment can make assessment and diagnosis of pain more difficult.
iii.For dementia or noncommunicative patients: The American Medical Directors Association has endorsed the Pain Assessment in Advanced Dementia (PAINAD) Scale scores for the following items:
•Breathing: Examples include normal, labored, hyperventilation.
•Negative vocalization: Examples include moaning, negative language, crying.
•Facial expression: Examples include smiling, frowning, grimacing.
•Body language: Examples include relaxed, tense, rigid, or striking out.
•Consolability: Examples include extent to which a caregiver is able to console, distract, or reassure.