Signs and Symptoms of Diverticulitis
Abdominal pain in the left lower quadrant is the hallmark presenting symptom of diverticulitis, typically acute or subacute in onset. 1
Cardinal Clinical Features
Primary Symptom:
- Left lower quadrant abdominal pain is the most common presenting complaint, though right-sided pain can occur with right-sided diverticulitis 1, 2
- Pain is typically acute or subacute in onset rather than chronic 1
- Abdominal tenderness on examination, localized to the affected area (usually left lower quadrant) 2
Associated Symptoms and Signs
Systemic manifestations:
- Fever is a common accompanying feature 1, 2
- Change in bowel habits (either constipation or diarrhea) 1
- Nausea without vomiting is characteristic—the presence of vomiting suggests more severe disease or complications 1
Laboratory abnormalities:
Important Clinical Nuances
The clinical presentation alone is insufficient for diagnosis. Clinical suspicion of diverticulitis based solely on symptoms and physical examination is correct in only 40-65% of patients 1. The 2020 WSES guidelines explicitly recommend against diagnosis based on clinical examination alone, noting that positive and negative predictive values of clinical diagnosis are only 0.65 and 0.98 respectively 1.
A clinical decision rule exists that can increase diagnostic accuracy: the combination of (1) direct tenderness only in the left lower quadrant, (2) CRP >50 mg/L, and (3) absence of vomiting identifies diverticulitis with 97% accuracy when all three features are present 1.
Distinguishing Uncomplicated from Complicated Disease
Uncomplicated diverticulitis presents with the above symptoms plus imaging findings of colon wall thickening and peri-colonic inflammatory changes only 1.
Warning features suggesting complicated disease:
- Persistent vomiting (suggests obstruction or more severe inflammation) 1
- Severe pain score (≥8/10) at presentation 1
- Symptoms lasting >5 days prior to presentation 1
- Signs of peritonitis (diffuse tenderness, rigidity, rebound) 1
- Hemodynamic instability or sepsis 1
Critical Diagnostic Pitfall
CT imaging is essential for confirmation. The AGA strongly recommends CT scan of the abdomen and pelvis with oral and intravenous contrast to confirm the diagnosis in patients without prior imaging-confirmed diverticulitis, evaluate for complications in severe presentations, and assess patients who fail to improve with therapy 1. CT has 95-99% sensitivity and 99-100% specificity for diagnosing acute diverticulitis 2.
Do not rely on symptoms alone to make treatment decisions, as multiple conditions can mimic diverticulitis, and the distinction between uncomplicated and complicated disease—which fundamentally changes management—requires imaging confirmation 1.