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Acute appendicitis
Obstruction of the appendiceal lumen leads to inflammation, ischaemia and finally perforation; the diagnosis is clinical, supported by a risk score and imaging, and the standard treatment is laparoscopic appendectomy.
Why it matters in the exam
The exam mostly tests choices: when clinical assessment is enough and when imaging is needed, which imaging to choose in a child, a pregnant woman or an adult, and what to do when the scan shows an abscess around the appendix rather than "simple" appendicitis. Other questions test the classic signs — pain that starts around the umbilicus and migrates to the right lower quadrant, Rovsing's sign, the psoas sign and the obturator sign — and how the position of the appendix (retrocaecal, pelvic) changes the clinical picture.
A recurring topic in recent years is antibiotics alone for uncomplicated appendicitis: it is a legitimate option for a selected patient, but a sizeable share — roughly a third — eventually have an appendectomy, and an appendicolith predicts failure and complications. Candidates are also asked about an incidental neuroendocrine tumour of the appendix and its treatment by size, and about the difference between a phlegmon, a contained abscess and perforation with generalised peritonitis — three situations with three different treatments.
Key points
- Pain migrates from the umbilicus to the right lower quadrant; Rovsing, psoas and obturator signs support the diagnosis.
- Alvarado 4 or less — low probability; 7 or more — high probability.
- Ultrasound first in children and in pregnancy; contrast CT in adults.
- Uncomplicated — laparoscopic appendectomy; antibiotics alone are an alternative in a selected patient without an appendicolith.
- Abscess of 3 cm or more — percutaneous drainage; generalised peritonitis — urgent surgery.
Summary table
| Situation | Key finding | Treatment | Exam note |
|---|---|---|---|
| Uncomplicated appendicitis | Pain migrating to the right lower quadrant, tenderness at McBurney's point, leucocytosis | Laparoscopic appendectomy; antibiotics alone are an alternative in a selected patient | An appendicolith on imaging predicts failure of non-operative treatment |
| Contained abscess | Abscess of 3 cm or more on CT in a stable patient | Percutaneous drainage and antibiotics | Over age 40 — colonoscopy and CT later to exclude a tumour |
| Phlegmon | Inflammatory mass without a drainable collection | Antibiotics; surgery only if no improvement | Interval appendectomy is not routine |
| Perforation with generalised peritonitis | Tenderness over the whole abdomen, fever, toxic patient | Resuscitation, antibiotics and urgent surgery | After source control about 4 days of antibiotics are enough |
| Incidental neuroendocrine tumour | Finding on histology | Up to 1 cm — appendectomy is enough; over 2 cm — right hemicolectomy | At 1–2 cm, extend the operation only when risk features are present |
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Sources
- WSES Jerusalem guidelines for the diagnosis and treatment of acute appendicitis, 2020 — Diagnosis, non-operative management and surgical treatment
- CODA Collaborative, New England Journal of Medicine, 2020 — A randomized trial comparing antibiotics with appendectomy for appendicitis
- Sabiston Textbook of Surgery, 21st edition (2022) — The Appendix
Sources are given for further reading; the text is written afresh and not copied from them.
Reviewed by the Examqo AI Professor · 2026-11-02. The text may contain errors; when in doubt, check the source.