What is the most appropriate next step in management for a patient with suspected appendicitis, presenting with right lower quadrant pain, anorexia, RLQ tenderness, rebound tenderness, and leukocytosis?

Management of Suspected Appendicitis with Classic Presentation

The most appropriate next step is CT abdomen and pelvis with IV contrast (Option A), as this patient presents with classic appendicitis findings requiring diagnostic confirmation before surgical intervention. 1, 2

Clinical Context and Risk Stratification

This patient demonstrates the classic triad of appendicitis:

• Right lower quadrant pain with anorexia 2, 3
• Peritoneal signs (rebound tenderness) 4
• Leukocytosis 4

While these findings are highly suggestive, they are present in only approximately 50% of appendicitis cases and warrant imaging confirmation before proceeding to surgery. 2, 3

Why CT is the Appropriate Next Step

CT abdomen and pelvis with IV contrast is the primary diagnostic imaging modality for suspected appendicitis in adults, achieving sensitivities of 85.7-100% and specificities of 94.8-100%. 1, 2

Key Advantages of CT:

• Reduces negative appendectomy rate from 25% (clinical diagnosis alone) to 1.7-7.7% with preoperative imaging 1
• Identifies alternative diagnoses in 94.3% of non-appendicitis cases, including colitis, diverticulitis, ovarian pathology, and urolithiasis 1
• Detects perforation and complications such as abscess formation, which fundamentally changes management 1, 3
• No delay in perforation rates despite time for imaging 1

Technical Specifications:

• IV contrast without oral contrast is preferred to avoid delays in diagnosis and treatment, with sensitivities of 90-100% and specificities of 94.8-100% 1, 2
• CT signs with highest accuracy include appendiceal diameter >8.2 mm (sensitivity 88.8%, specificity 93.4%) and periappendiceal fat stranding 1

Why Other Options Are Inappropriate

Option B (IVF & Observation):

• Observation without imaging is unacceptable given the high clinical suspicion and risk of perforation with delayed diagnosis 1, 4
• Perforation occurs in 17-32% of appendicitis cases and is associated with increased morbidity, mortality, and length of stay 1, 4
• Clinical examination alone has an unacceptably high negative appendectomy rate of 25% 1

Option C (Open Appendectomy):

• Proceeding directly to surgery without imaging risks unnecessary operations, particularly in females where the negative appendectomy rate can reach 50% without CT 5
• CT findings of appendicolith, mass effect, or appendiceal diameter >13 mm identify patients at higher risk for complications and treatment failure with antibiotics, guiding appropriate surgical planning 3
• Imaging may reveal alternative diagnoses requiring different management 1

Option D (Discharge):

• Discharge is contraindicated with classic appendicitis presentation and would risk catastrophic perforation 4, 6

Clinical Decision Algorithm

For patients with Alvarado scores ≥7 (which this patient likely has):

• CT imaging is still recommended before surgery to confirm diagnosis, assess for perforation, and rule out alternative diagnoses 1, 6
• Surgical consultation should occur concurrently with imaging to expedite definitive management 4, 6

Critical CT findings that guide management:

• Appendiceal diameter ≥7 mm confirms appendicitis 3
• Appendicolith, mass effect, or diameter >13 mm indicate higher surgical risk and contraindicate antibiotics-first approach 3
• Periappendiceal abscess may warrant percutaneous drainage before interval appendectomy 1

Common Pitfalls to Avoid

• Do not rely on clinical scoring systems alone (Alvarado score) without imaging, as they have mixed results and cannot replace diagnostic confirmation 1, 6
• Do not delay imaging for oral contrast administration, as IV contrast alone is sufficient and avoids treatment delays 1, 2
• Do not assume ultrasound is adequate in adults, as sensitivities are only 51.8-81.7% compared to CT's 85.7-100% 2