Acute appendicitis is an acute inflammation of the vermiform appendix.
Typically presents as acute abdominal pain starting in the mid-abdomen and later localizing to the right lower quadrant.
Associated with fever, anorexia, nausea, vomiting, and elevation of the neutrophil count.
Diagnosis is usually made clinically. If investigation is required, computed tomography scan or ultrasonography may show dilatation of the appendix outer diameter to more than 6 mm.
Definitive treatment is surgical appendectomy. A nonoperative, antibiotic-only approach may be feasible in select patient populations.
History and exam
Key diagnostic factors
- abdominal pain
- right lower quadrant tenderness
Other diagnostic factors
- age of occurrence
- diminished bowel sounds
- Rovsing sign
- psoas sign
- obturator sign
- <6 months of breastfeeding
- low dietary fiber
- improved personal hygiene
1st investigations to order
- abdominal and pelvic CT scan
- urinary pregnancy test
Investigations to consider
- abdominal ultrasound
- abdominal and pelvic MRI in pregnancy
uncomplicated acute appendicitis
ill with perforation or abscess
- Acute mesenteric adenitis
- Viral gastroenteritis
- Meckel diverticulitis
- ACR Appropriateness Criteria: right lower quadrant pain - suspected appendicitis
- WSES Jerusalem guidelines for diagnosis and treatment of acute appendicitis
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