Can appendicitis present without fever, particularly in certain populations such as the elderly, young children, and immunocompromised individuals?

Can Appendicitis Present Without Fever?

Yes, appendicitis frequently presents without fever, and the absence of fever should never be used to exclude the diagnosis—particularly in elderly patients where fever is present in only 30-80% of cases. 1

Key Clinical Reality

The classic triad of migrating right lower quadrant pain, fever, and leukocytosis is infrequently observed in actual clinical practice, especially in elderly patients. 1 Only a minority of patients present with all typical signs and symptoms together. 1

Population-Specific Presentations

Elderly Patients (>65 years)

• Fever is present in only 30-80% of elderly patients with confirmed appendicitis, meaning 20-70% present without fever. 1
• These patients more commonly present with signs of ileus or bowel obstruction rather than classic appendicitis symptoms. 1
• Right lower quadrant tenderness, nausea, and vomiting remain common even without fever. 1
• The World Journal of Emergency Surgery strongly recommends against basing the diagnosis of acute appendicitis in elderly patients only on clinical signs and symptoms (including fever). 1

Immunocompromised Patients

• The most frequent presenting symptom is fever, but it is followed by non-specific intermittent abdominal pain rather than classic presentation. 2
• These patients experience significant diagnostic delays (median 4 days) precisely because presentations are atypical. 2
• Appendicitis in immunosuppressed patients is associated with increased morbidity and mortality due to diagnostic difficulty. 2

General Adult Population

• The American College of Emergency Physicians explicitly states that laboratory test results (including markers of fever/inflammation) may be normal in the setting of appendicitis. 3
• Appendicitis can occur without elevated white blood cell count, and by extension, without fever. 3
• Early appendicitis may not yet demonstrate laboratory abnormalities or fever. 3

Critical Diagnostic Approach

What NOT to Do

• Never rule out appendicitis based solely on absence of fever. 3
• Do not rely on the "classic triad" as a requirement for diagnosis. 1
• Do not use clinical signs and symptoms alone (including fever status) to diagnose or exclude appendicitis, especially in elderly patients. 1

What TO Do

• Use clinical findings to risk-stratify patients rather than relying on presence or absence of individual symptoms like fever. 3
• Employ validated scoring systems (Alvarado, AIR score) that incorporate multiple clinical parameters, not just fever. 1, 3
• Proceed with imaging (CT or ultrasound) even when fever is absent if clinical suspicion exists. 3
• Recognize that intermediate-risk patients require systematic diagnostic imaging regardless of fever or laboratory values. 3

Common Pitfalls to Avoid

1. Anchoring bias on "classic presentation": The typical triad is actually uncommon in real practice, particularly in vulnerable populations. 1

2. Delayed diagnosis in afebrile patients: This is especially dangerous in elderly patients who already have 18-70% perforation rates compared to 3-29% in younger patients. 4

3. Gender bias: Women and girls presenting with abdominal pain without fever are at higher risk of missed appendicitis (AOR 1.68 for women, 1.64 for girls). 5

4. Comorbidity confusion: Patients with comorbidity index ≥2 presenting with abdominal symptoms without fever have 3-5 times higher odds of missed appendicitis. 5

Clinical Bottom Line

Fever is neither sensitive nor specific for appendicitis. Its absence should prompt the same rigorous diagnostic evaluation as its presence, using validated clinical scoring systems combined with appropriate imaging. This is particularly critical in elderly, immunocompromised, and female patients where atypical presentations are the norm rather than the exception. 1, 3, 5, 2