Diverticulosis vs. Diverticulitis: Distinguishing features
Authors: Sahil Prabhnoor Sidhu, Vadim Iablokov, Vina Fan Reviewers: Brandon Hisey, Laura Byford-Richardson, Raafi Ali Dr. Sylvain Coderre* * MD at time of publication
Local inflammation
Diverticulitis
Inflammation of diverticuli
Conditions causing inherent
weakness in bowel wall, i.e. aging, Ehlers-Danlos syndrome, Marfan syndrome
Risk factors (i.e. low fiber diet, obesity, inactivity, smoking) contributing to reduced gut motility
↑Intraluminal pressure in the colon
Herniation of colonic mucosa and submucosa through circular muscle at points of weakness to form outpouchings
Diverticulosis
Presence of outpouchings in the colon (diverticuli)
Note: In Western populations, most diverticulosis is left-sided, whereas in Asian populations, these outpouchings are more often right-sided.
Mucosal abrasion or micro-perforation by ↑ intraluminal pressure or dense food particles
Bacterial overgrowth,
dysbiosis and passage into the lamina propria
Feces collects in diverticuli
Gut bacteria metabolize undigested material and produce gas
Stretching of colon Bloating wall irritates and
visceral afferent flatulence nerves
Episodic abdominal discomfort and cramping
Blood vessels in
the mucosa and submucosa (vasa recta) are stretched over the diverticuli, and may rupture from ↑ pressure
Diverticular bleed
Painless hematochezia (passage of fresh blood from the rectum)
Inflammatory cytokines activate clotting factors
Clotting of blood in vessels supplying diverticula
Inflammatory cytokine release (IL-6, TNF-α)
Cytokines enter systemic circulation
Edema in the bowel wall
Irritation of adjacent parietal peritoneum and somatic nerves
Left lower quadrant (LLQ) pain, guarding
Small abrasions are walled off by pericolic fat and mesentery
↑WBC
Fever
Inflammation may spread to nearby organs, leading to ulceration and abnormal connections between organs
Pericolic abscess
No hematochezia
Local ischemia and focal necrosis resulting in loss of integrity of the bowel wall
Perforation
Generalized peritonitis
Colonic obstruction (rare)
Fistulae (rare): i.e. colovesical, coloenteric
Stricture/fibros is formation with healing
Legend:
Pathophysiology
Mechanism
Sign/Symptom/Lab Finding
Complications
Published October 12, 2016; Updated July 30, 2023 on www.thecalgaryguide.com