What is the next step in managing a patient with symptoms of appendicitis, including nausea, vomiting, and positive rebound tenderness?

Next Step: Obtain Abdominal Imaging (CT or Ultrasound)

The next step is to obtain diagnostic imaging—specifically CT abdomen/pelvis with IV contrast (preferred) or ultrasound—before proceeding to surgery, as imaging is essential to confirm the diagnosis and guide appropriate management in this patient with suspected but not definitively diagnosed appendicitis. 1

Clinical Context and Diagnostic Uncertainty

This patient presents with incomplete classic appendicitis features:

• Present: Nausea, vomiting, positive rebound tenderness (peritoneal signs)
• Notably absent: Anorexia, fever, leukocytosis

The absence of anorexia is particularly significant, as the classic appendicitis sequence includes periumbilical pain, anorexia, nausea/vomiting, then migration to the right lower quadrant. 1, 2 The classic presentation occurs in only approximately 50% of patients, and the absence of fever and leukocytosis further increases diagnostic uncertainty. 1, 2

Why Imaging is Mandatory Before Surgery

Guideline-based imaging recommendations:

• Although no clinical findings are unequivocal in identifying appendicitis, a constellation of findings including characteristic abdominal pain, localized tenderness, and laboratory evidence of acute inflammation will generally identify most patients—but this patient lacks the laboratory inflammation markers. 1

• Helical CT of the abdomen and pelvis with intravenous contrast (without oral or rectal contrast) is the recommended imaging procedure for patients with suspected appendicitis, with sensitivity of 85.7-100% and specificity of 94.8-100%. 1, 2

• For patients with suspected appendicitis that can neither be confirmed nor excluded by clinical evaluation alone, careful follow-up is recommended, and patients may be hospitalized if the index of suspicion is high. 1

Imaging Algorithm

Primary imaging choice:

• CT abdomen/pelvis with IV contrast (no oral/rectal contrast): Sensitivity 90-100%, specificity 94.8-100%. This is the gold standard for adults. 1, 2

Alternative if CT unavailable or contraindicated:

• Ultrasound: Reasonable first-line option, though sensitivity is more variable (51.8-81.7%) and operator-dependent. The appendix is not visualized in up to 45% of cases. 1, 3

Why Other Options Are Incorrect

Open appendectomy without imaging would be premature and risks unnecessary surgery given the diagnostic uncertainty and absence of classic inflammatory markers. The historical negative appendectomy rate of 14.7% with clinical diagnosis alone has been reduced to 1.7-7.7% with preoperative CT. 1

Discharge with antibiotics is inappropriate—this patient has peritoneal signs (positive rebound tenderness) indicating potential surgical pathology that requires definitive diagnosis. 1

Admission for 24-hour observation alone without imaging is suboptimal. While observation is acceptable for equivocal cases, it should be combined with imaging to establish a diagnosis. 1 Patients with high clinical suspicion should receive imaging promptly rather than prolonged observation that delays definitive management. 1

Critical Management Points After Imaging

If imaging confirms appendicitis:

• Initiate broad-spectrum antibiotics immediately (covering gram-negative and anaerobic organisms) 1
• Proceed to appendectomy (laparoscopic or open) as soon as reasonably feasible 1, 4

If imaging is negative:

• 24-hour follow-up is mandatory due to measurable false-negative rates 1, 2
• Consider alternative diagnoses for the abdominal pain 1

If imaging is equivocal:

• Admit for observation with antimicrobial therapy and serial examinations 1
• Consider repeat imaging or diagnostic laparoscopy if clinical deterioration occurs 1

Common Pitfalls to Avoid

• Do not proceed to surgery based solely on rebound tenderness without imaging confirmation, especially when fever and leukocytosis are absent—this increases negative appendectomy rates. 1

• Do not delay imaging in favor of prolonged clinical observation when imaging is readily available—early imaging improves diagnostic accuracy and reduces perforation risk. 1, 5

• Do not assume absence of fever/leukocytosis excludes appendicitis, but recognize it increases diagnostic uncertainty and strengthens the need for imaging. 2, 5