Cirugía 2025 18/09/2025

Summary

Marcelo Pontillo presents a lecture on colonic diverticular disease, focusing on how diverticula form, how acute diverticulitis is classified and treated, and how to recognize its other complications.

1. Diverticulosis and How Diverticula Form

• Diverticulosis means diverticula are present in the colon. They most commonly occur in the sigmoid colon, though they can affect other parts or, less often, the entire colon.
• Colonic diverticula are generally pseudodiverticula: the mucosa and submucosa protrude through the muscular wall. This differs from a true diverticulum, which involves all layers of the intestinal wall.
• Diverticula tend to form at weak points where blood vessels pass through the colon’s muscle layer.
• The lecture describes two central contributors:
  • Increased pressure inside the colon, associated with segmental contractions and a low-fiber diet.
  • A thicker, less flexible colon wall, associated with aging and changes to collagen and elastic fibers.
• Other potential risk factors discussed include obesity, genetic factors, neuromuscular changes, and connective-tissue disorders.

Diverticulosis is often found incidentally. The lecturer estimates that many people with diverticula have no symptoms, a smaller proportion experience mild symptoms, and only a minority develop complications. Its frequency increases with age.

For symptomatic diverticulosis, the lecture recommends a fiber-rich diet and physical activity. It also discusses cyclical rifaximin and probiotics for some symptomatic patients. Avoiding seeds or legumes is described as a common recommendation, but there is no evidence that it prevents complications.

2. Acute Diverticulitis

Acute diverticulitis is inflammation or infection involving a diverticulum. The lecture explains that repeated impaction of hard stool can injure the diverticular lining, provoke inflammation and bacterial growth, and sometimes cause a small perforation. A small perforation may seal off; a larger one can lead to widespread contamination of the abdomen.

Symptoms and Assessment

Common features include:

• Persistent abdominal pain, usually in the left lower abdomen.
• Fever or low-grade fever, nausea, vomiting, reduced appetite, or a change in bowel habits.
• Localized tenderness, and sometimes guarding or a palpable mass.
• Urinary symptoms, which can occur if an inflamed sigmoid colon lies against the bladder.

A long or mobile sigmoid colon can make the pain appear in a different location. Other diagnoses, including appendicitis, may therefore need to be considered.

Assessment may include blood tests for inflammation and imaging. Ultrasound can help, but its usefulness depends on equipment and operator skill. CT with intravenous contrast is presented as the preferred imaging test, because it can show inflammation, collections, and free gas.

Important alternative diagnoses include colorectal cancer, inflammatory or infectious colitis, appendicitis, and epiploic appendagitis.

Modified Hinchey Stages Discussed

The lecturer presents a CT-based classification and clarifies the distinction between the two stage-2 categories:

• Stage 0: Diverticula with bowel-wall thickening and inflammation in the surrounding fat, but no collection or free gas.
• Stage 1A: Small amounts of pericolic gas or fluid close to the inflamed segment, without an abscess.
• Stage 1B: A small abscess, less than 4 cm.
• Stage 2A: An abscess larger than 4 cm.
• Stage 2B: Gas distant from the inflamed segment, without diffuse free fluid.
• Stage 3: Diffuse fluid consistent with purulent peritonitis, without distant free gas.
• Stage 4: Diffuse fluid plus distant free gas, suggesting a major perforation and fecal peritonitis.

Treatment Approach

Uncomplicated Disease (Stage 0)

• The lecture describes initial bowel rest and a liquid diet, followed by a temporary low-residue diet until the pain settles, then a return to a high-fiber diet.
• Paracetamol is preferred over non-steroidal anti-inflammatory drugs in the approach described.
• Antibiotics are not considered necessary for every otherwise healthy patient with uncomplicated disease. The lecturer recommends them when there are concerning features, such as significant systemic symptoms, relevant comorbidities, immune compromise, elevated inflammatory markers, or free fluid.
• Outpatient follow-up is generally planned within 48–72 hours. Patients needing closer monitoring may be admitted for intravenous treatment.

Stage 1A: Small, Nearby Pericolic Gas or Fluid

• The lecturer recommends admission, intravenous antibiotics, and close clinical monitoring in most cases.
• Selected patients may be managed through home-hospital services if adequate monitoring is available.
• Gas near the colon does not automatically mean surgery is required.

Stage 1B: Abscess Smaller Than 4 cm

• This is usually treated with hospital admission and intravenous antibiotics.
• The lecture reports that many such abscesses respond without a procedure.

Stage 2A: Abscess Larger Than 4 cm

• Give antibiotics and consider image-guided percutaneous drainage as the preferred next step when a safe route is available.
• If drainage is not feasible or fails, laparoscopic drainage may be considered.
• Surgery, including sigmoid resection, may be needed if the patient deteriorates, develops organ dysfunction or diffuse peritonitis, or does not respond to less invasive treatment.
• The lecturer emphasizes considering the patient’s condition alongside the CT findings.

Stage 2B: Distant Gas Without Diffuse Fluid

• In carefully selected, stable patients without diffuse peritonitis or organ dysfunction, the lecture supports an initial non-operative approach with intravenous antibiotics and close monitoring.
• This approach can fail, so ongoing reassessment is important. The lecturer notes that free gas alone is not necessarily an indication for immediate surgery.

Stage 3: Purulent Peritonitis

The options discussed are laparoscopic lavage and drainage, or sigmoidectomy.

During lavage, the surgeon checks for a larger perforation. If one is found, bowel resection is required; if not, drainage may be sufficient initially. Lavage may avoid immediate bowel resection in some patients, but recurrence or later intervention is possible. The choice depends on patient selection and operative findings.

Stage 4: Fecal Peritonitis

The lecture describes emergency open surgery and a Hartmann-type operation as the standard approach for this severe presentation.

3. Other Complications

Diverticular Bleeding

• Diverticular disease is described as an important cause of lower gastrointestinal bleeding in older adults.
• Bleeding can occur when a vessel associated with a diverticulum is damaged.
• The lecturer says most episodes stop spontaneously; severe or persistent bleeding may require further investigation or intervention.

Fistulas

• A diverticular abscess or persistent inflammation can erode into a neighboring organ.
• The most common example discussed is a colovesical fistula, which may cause recurrent urinary infections, pneumaturia (air in the urine), or fecaluria (stool in the urine).
• Evaluation should identify the cause—particularly by distinguishing diverticular disease from cancer—and locate the fistula. The lecture mentions cystoscopy and imaging.
• Treatment generally involves resecting the diseased colon segment and addressing the affected organ. Other possible fistulas include connections to bowel or skin.

Stenosis

• Repeated inflammation and healing can produce fibrosis and narrowing of the colon.
• Symptoms may include abdominal distension, cramping, difficulty passing stool or gas, and potentially bowel obstruction.
• Colorectal cancer must be excluded. The lecture identifies sigmoidectomy as the effective treatment for symptomatic diverticular stenosis.

4. Follow-Up and Planned Surgery

• An elective sigmoidectomy is not automatically required after one episode. It may be considered for patients with repeated episodes, hospitalizations, prolonged treatment, or a substantial effect on quality of life.
• Colonoscopy is used to help exclude underlying colorectal cancer. The lecturer advises waiting roughly six to eight weeks after an acute episode, especially after complicated diverticulitis, rather than performing it while the colon is inflamed.
• The lecture notes that diverticula most often affect the sigmoid colon and are not expected in the rectum.

Speakers and Sources Featured

• Marcelo Pontillo — lecturer; identified himself as an assistant in Surgical Unit F.
• Unidentified course participants — asked questions and commented during the online lecture.
• Sources and frameworks cited by the lecturer: the Hinchey classification, a modified CT-based classification associated with 2020 guidance, and unspecified studies or articles from 2011, 2014, and 2020. No other named speakers are featured.