Acute Appendicitis
Direct answer
Acute appendicitis is obstruction-driven inflammation of the vermiform appendix, classically presenting with periumbilical pain that migrates to the right iliac fossa over hours, with anorexia, nausea and low-grade fever. Diagnosis is clinical, supported by ultrasound as the usual first imaging test (CT where available), and definitive treatment is appendicectomy — laparoscopic where feasible — with antibiotics covering the transition to surgery.
What you must remember
- Pain migration is the clue: visceral periumbilical pain (T10) shifts to the right iliac fossa once parietal peritoneum is inflamed; anorexia almost always accompanies onset.
- McBurney's point: one-third of the distance from the anterior superior iliac spine to the umbilicus — the site of maximal tenderness in the usual anatomical position.
- Signs by position: retrocaecal appendix irritates the psoas (psoas sign); pelvic appendix irritates the obturator (obturator sign); Rovsing's sign is right-sided pain on left-sided palpation.
- Scores: the Alvarado (MANTRELS) and AIR scores stratify probability and guide imaging and admission decisions.
- Imaging: ultrasound is the usual first-line test (children, pregnancy, resource-limited settings); CT abdomen is the most sensitive and specific where available; MRI if ultrasound is inconclusive in pregnancy.
- Treatment: laparoscopic appendicectomy is the standard; an antibiotic-first strategy is an accepted option for uncomplicated appendicitis in selected, counselled patients, accepting a risk of recurrence.
- Appendicular mass: initial conservative management with antibiotics, with interval appendicectomy considered selectively; a periappendicular abscess needs drainage.
Common confusion
Right iliac fossal pain has a crowded differential, and exam stems deliberately populate it: mesenteric adenitis (children, preceding viral illness), Meckel's diverticulitis, terminal ileitis of Crohn's disease, right-sided ureteric colic (pain radiating to groin, haematuria), and in women ovarian torsion, ruptured cyst and ectopic pregnancy — the reason a urine pregnancy test is mandatory in every woman of reproductive age with this presentation. Remember atypical appendicitis positions too: a pelvic appendix mimics gastroenteritis with diarrhoea and tenesmus, a retrocaecal appendix may have minimal anterior signs, and pregnancy displaces the appendix upward and outward, masking the classic picture. Elderly and diabetic patients often present late with subtle signs and a higher perforation rate.
Exam-focused takeaway
NEET-PG questions on appendicitis test recognition and steps: the pathophysiology of migratory pain, named signs and their mechanisms, components of the Alvarado score, the first-line imaging choice by patient group, and management forks — early appendicectomy versus conservative treatment of an appendicular mass, drainage of an abscess, and antibiotic-first selection for uncomplicated disease. Anatomy questions target blood supply (appendicular artery, an end artery prone to gangrene) and positions of the appendix. Image-based stems show the CT with a thickened, fat-stranded appendix or an appendicolith. Next-best-step vignettes hinge on the pregnancy test in women and on recognising perforation.
Practise previous-year and exam-style appendicitis questions inside the PrepElephant app — topic-wise practice, full-length mocks and revision tools that resurface your flagged stems.
Frequently asked questions
What is the classic pain sequence of appendicitis?
Periumbilical visceral pain migrating to the right iliac fossa as parietal peritoneum becomes inflamed, with anorexia, nausea and later fever.
Which imaging is first-line for suspected appendicitis?
Ultrasound in most settings, especially children and pregnancy; CT abdomen where available for uncertain cases in adults, MRI if still unsure in pregnancy.
What is McBurney's point?
One-third along the line from the anterior superior iliac spine to the umbilicus, marking maximal tenderness over the base of the appendix.
How is an appendicular mass managed?
Initially conservative — antibiotics, fluids, monitoring — with interval appendicectomy considered selectively; a formed abscess requires drainage.
Can appendicitis be treated with antibiotics alone?
Yes, selected uncomplicated cases may be managed antibiotic-first with careful follow-up, accepting a real risk of recurrence and missed progression.
Which position of the appendix is commonest?
The retrocaecal position is the commonest, which is why a psoas sign and a less typical presentation accompany it.
Practise this in the PrepElephant app
Question banks, previous-year questions, mock tests and revision tools — for Acute Appendicitis and Surgery. Free to start.