What are the typical symptoms and treatment options for appendicitis?

Appendicitis: Clinical Presentation and Management

Classic Symptom Triad

The hallmark presentation of appendicitis consists of periumbilical pain migrating to the right lower quadrant, anorexia/nausea with intermittent vomiting, and low-grade fever, though this classic triad occurs in only approximately 50% of patients. 1, 2

Key Clinical Features in Adults

• Pain migration: Vague periumbilical pain that localizes to the right lower quadrant is the most reliable diagnostic feature 2, 3
• Right lower quadrant tenderness: Present in the majority of cases and highly predictive when combined with abdominal rigidity 3
• Anorexia and nausea: Nearly universal findings that precede vomiting 2
• Fever: Typically low-grade (ranges 30-80% in elderly), though absence does not exclude appendicitis 1
• Peritoneal signs: Rebound tenderness, guarding, and rigidity indicate more advanced disease 1, 3

Physical Examination Findings in Children

• Decreased or absent bowel sounds: Most reliable sign for ruling in appendicitis 3
• Psoas sign: Pain with right hip extension (positive when inflamed appendix irritates psoas muscle) 3
• Obturator sign: Pain with internal rotation of flexed right hip 3
• Rovsing sign: Right lower quadrant pain with left lower quadrant palpation 3

Atypical Presentations Requiring High Suspicion

In elderly patients (>65 years), the diagnosis is significantly more challenging with lower rates of correct preoperative diagnosis and higher perforation rates (55-70%) due to delayed presentation. 1

• Elderly patients may present with ileus or bowel obstruction symptoms rather than classic findings 1
• Women of childbearing age have broader differential diagnosis requiring mandatory imaging before surgery 4
• Pregnant patients require ultrasound or MRI to avoid radiation exposure 4

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Diagnostic Approach

Clinical Scoring Systems

Scoring systems like the Alvarado score are useful for excluding appendicitis with low scores, but should never be used alone to diagnose appendicitis. 1, 3

• The Alvarado score, Pediatric Appendicitis Score, and Appendicitis Inflammatory Response score stratify patients as low, moderate, or high risk 3
• Critical caveat: In elderly patients, scoring systems have conditional recommendation only for exclusion, not diagnosis 1

Laboratory Testing

Laboratory tests of inflammatory response (WBC, CRP) are strongest discriminators when combined with clinical findings, but cannot establish diagnosis alone. 1

• Two or more elevated inflammatory markers make appendicitis likely 1
• All normal inflammatory markers make appendicitis unlikely 1
• In elderly patients, normal WBC and CRP have 100% negative predictive value for excluding appendicitis 1
• Procalcitonin (AUC 0.94) helps identify complicated appendicitis 1

Imaging Strategy

Diagnostic imaging is now standard for most patients with suspected appendicitis and should be performed before surgery, except in males <40 years with classic presentation. 1

First-Line Imaging by Patient Population

• Non-pregnant adults: Contrast-enhanced CT (sensitivity 90.8%, specificity 94.2%) is preferred 1, 5
• Women of childbearing age: Pregnancy test first, then ultrasound, followed by MRI or low-dose CT if inconclusive 4
• Pregnant patients: Ultrasound first-line, MRI if ultrasound non-diagnostic 4
• Children: Point-of-care ultrasound (sensitivity 87.1%, specificity 89.2%) as first-line 4, 5

CT Protocol Specifications

Contrast-enhanced CT without enteral contrast is preferred, achieving sensitivity 90-100% and specificity 94.8-100% without delays from oral contrast administration. 1

• Low-dose CT protocols (2 mSv) achieve non-inferiority to standard-dose CT in patients 15-44 years 1
• CT findings predicting treatment failure with antibiotics: appendicolith, appendiceal diameter ≥13mm, mass effect 2

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Treatment Options

Surgical Management (First-Line for Most Patients)

Laparoscopic appendectomy is the preferred definitive treatment, offering shorter hospital stays, less pain, and lower surgical site infection rates compared to open surgery. 4, 1

Timing of Surgery

• Prompt surgical referral is warranted when diagnosis is clear 1, 3
• Delayed appendectomy (in-hospital delay) does not increase perforation risk in uncomplicated cases 1
• Perforation risk increases with prolonged symptom duration before presentation (17-32% perforation rate overall) 3

Antibiotic Prophylaxis for Surgery

A single preoperative dose of broad-spectrum antibiotics should be given 0-60 minutes before skin incision for uncomplicated appendicitis, with no postoperative antibiotics needed. 6

Recommended single-agent regimens (per Infectious Diseases Society of America): 6

• Ticarcillin-clavulanate
• Cefoxitin
• Ertapenem
• Moxifloxacin
• Tigecycline

Recommended combination regimens: 6

• Metronidazole PLUS (cefazolin, cefuroxime, ceftriaxone, levofloxacin, or ciprofloxacin)

Antibiotics to avoid: Ampicillin-sulbactam, cefotetan, clindamycin, aminoglycosides 6

Non-Operative Management (Selected Cases Only)

Antibiotic-only treatment successfully treats uncomplicated appendicitis in approximately 70% of patients, but carries a 27-37% recurrence rate within one year. 2, 4

Patient Selection Criteria for Antibiotics-First Approach

Non-operative management should only be considered in patients WITHOUT high-risk CT findings who strongly prefer to avoid surgery. 2, 4

Exclude from antibiotic-only approach (recommend surgery): 2

• Appendicolith on CT
• Appendiceal diameter ≥13mm
• Mass effect on CT
• Pregnant patients
• Immunosuppressed patients
• Elderly patients with peritoneal signs

Acceptable candidates for antibiotics-first: 2

• CT-proven uncomplicated appendicitis
• No appendicolith
• Appendiceal diameter <13mm
• Patient strongly prefers to avoid surgery
• Medically unfit for surgery without high-risk CT findings

Antibiotic Regimens for Non-Operative Management

Broad-spectrum coverage against gram-negative organisms and anaerobes is required, with piperacillin-tazobactam monotherapy or combination therapy (cephalosporin/fluoroquinolone PLUS metronidazole) as acceptable options. 2, 6

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Management of Complicated Appendicitis

Perforated Appendicitis with Abscess or Phlegmon

Non-operative management with antibiotics and percutaneous drainage (if accessible) is reasonable first-line treatment for appendiceal abscess, though laparoscopic surgery in experienced hands is equally safe. 1

• Percutaneous catheter drainage has 70-90% efficacy for mature abscesses >3cm 1
• After successful non-operative management, 80% of patients are cured without surgery 1
• Postoperative antibiotics should not exceed 3-5 days with adequate source control 6, 1

Interval Appendectomy Recommendations

Routine interval appendectomy is NOT recommended after successful non-operative management in young adults (<40 years) and children, as only 12-24% experience recurrence. 1

Interval appendectomy IS recommended for: 1

• Patients ≥40 years old (due to 3-17% incidence of appendiceal neoplasms)
• Patients with recurrent symptoms
• Colonoscopy and interval CT should be performed in patients ≥40 years treated non-operatively 1

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Critical Pitfalls to Avoid

• Never proceed to appendectomy in females without imaging confirmation due to broader differential diagnosis 4
• Do not base diagnosis on clinical signs alone in elderly patients (strong recommendation) 1
• Do not routinely cover Enterococcus in community-acquired appendicitis 6
• Avoid quinolones unless local E. coli susceptibility ≥90% 6
• Do not prolong antibiotics beyond 3-5 days postoperatively in complicated cases with adequate source control 6, 1
• Do not delay imaging in atypical presentations as perforation risk increases with diagnostic delay 3, 7