Diverticular Disease

Diverticular Disease - Gut's Little Pockets

• Definition: Outpouchings of intestinal wall.
  • True: All gut layers (e.g., Meckel's).
  • False (Pseudo): Mucosa & submucosa herniate through muscularis propria. 📌 "False lacks Muscle".
• Epidemiology: Affects elderly (>60 yrs), associated with Western diet (low fiber).
• Pathophysiology:
  • Low fiber → ↓ stool bulk → ↑ intraluminal pressure & segmentation.
  • Occurs at weak points (vasa recta penetration).
  • Law of Laplace: $P = 2T/R$.
• Most Common Site: Sigmoid colon (>90%).

  ⭐ Sigmoid colon is the most common site for diverticula (>90%) due to its narrowest lumen, leading to the highest intraluminal pressure according to Laplace's Law. oka

Clinical Features & Diagnosis - Pouch Problems Unveiled

• Diverticulosis: Majority asymptomatic; often an incidental finding.
• Symptomatic Uncomplicated Diverticular Disease (SUDD): Recurrent LLQ abdominal pain, bloating, altered bowel habits (constipation/diarrhea). No signs of acute inflammation.
• Acute Diverticulitis:
  • Classic: Left Lower Quadrant (LLQ) pain, tenderness.
  • Systemic: Fever, chills, ↑leukocytosis.
  • Associated: Nausea, vomiting, change in bowel habits.
• Diverticular Bleeding:
  • Abrupt, painless, large-volume hematochezia (bright red blood per rectum).
  • Often self-limiting; colonoscopy may be needed for localization/treatment.

⭐ CT scan (abdomen/pelvis with IV and oral contrast) is the investigation of choice for suspected acute diverticulitis, showing bowel wall thickening, pericolic fat stranding, and potential abscess/perforation.

Classification & Complications - When Pockets Go Rogue

Modified Hinchey Classification

Complications:

• Abscess: Localized pus collection. Percutaneous drainage if >4 cm.
• Phlegmon: Cellulitis/inflammation of pericolic fat without discrete abscess.
• Fistula: Abnormal tract.
  • Colovesical (most common): Colon to bladder ➔ pneumaturia, fecaluria. 📌 Mnemonic: "Bladder Breathes & Poops" (Pneumaturia & Fecaluria).
  • Colovaginal, coloenteric, colocutaneous.
• Stricture: Fibrotic narrowing leading to obstruction.
• Perforation: Free rupture into peritoneum.
• Obstruction: Bowel blockage from stricture or inflammation.
• Bleeding: Lower GI hemorrhage, often painless.

⭐ Colovesical fistula is the most common type of internal fistula in complicated diverticulitis, classically presenting with pneumaturia and fecaluria.

Management Strategies - Taming the Outpouchings

• Asymptomatic Diverticulosis: High-fiber diet to prevent progression.
• Symptomatic Uncomplicated Diverticular Disease (SUDD): High-fiber diet; antispasmodics for pain.
• Acute Uncomplicated Diverticulitis:
  • Outpatient (mild): Clear liquids, oral antibiotics (e.g., ciprofloxacin + metronidazole).
  • Inpatient (severe/comorbid): IV antibiotics, bowel rest, analgesia.
• Complicated Diverticulitis (abscess, perforation, etc.):
  • Hinchey I/II (small abscess <4cm): IV antibiotics.
  • Hinchey I/II (abscess >4cm): Percutaneous drainage + IV antibiotics.
  • Hinchey III/IV (peritonitis): Emergency surgery - Hartmann's or primary anastomosis ± diversion.
• Elective Colectomy:
  • Indications: After 1 complicated episode; ≥2 uncomplicated episodes needing hospitalization; immunosuppression.

⭐ Hartmann's procedure is often performed for Hinchey stage III/IV purulent or fecal peritonitis, involving resection of the diseased segment, end colostomy, and oversewing the rectal stump.

High‑Yield Points - ⚡ Biggest Takeaways

• Sigmoid colon: Most common site due to high intraluminal pressure.
• Low-fiber diet: Key risk factor for diverticulosis.
• Acute diverticulitis: LLQ pain, fever; CT scan is investigation of choice.
• Complications: Abscess, colovesical fistula (most common), perforation (Hinchey).
• Hinchey classification: Guides surgical management of perforated diverticulitis.
• Diverticular hemorrhage: Common cause of painless massive LGIB; often right-sided.
• Hartmann's procedure: Often performed for Hinchey III/IV or unstable patients_._