Appendicitis in Children
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Direct answer
Appendicitis in children is acute inflammation of the vermiform appendix, most often diagnosed in school-age children and adolescents, and harder to recognise in infants and toddlers. The classic picture is periumbilical pain migrating to the right iliac fossa, with anorexia, vomiting and fever. Clinical scores such as the Alvarado score and the Paediatric Appendicitis Score guide imaging, and perforation risk is highest in the very young.
What you must remember
- Classic sequence: periumbilical colicky pain migrating to the right lower quadrant, with anorexia and vomiting, is typical in older children but not universal.
- Young children: infants and toddlers present late with fever, irritability and generalised abdominal pain, and perforation is far more common.
- Alvarado score: a ten-point score built from migration, anorexia, nausea and vomiting, right iliac fossa tenderness, rebound, fever, leucocytosis and left shift, where higher totals raise suspicion.
- Paediatric Appendicitis Score: a score designed specifically for children, combining clinical and laboratory features.
- Ultrasound: graded compression ultrasonography is first-line imaging, and a non-compressible appendix more than 6 mm in diameter supports the diagnosis.
- CT: reserved for equivocal ultrasound, with low-dose protocols used to limit radiation exposure in children.
- Treatment: appendicectomy remains the standard, while antibiotics alone are an option in selected uncomplicated cases, depending on local practice.
A structured path from score to imaging to surgery
Appendicitis is a clinical diagnosis supported by scores and imaging, and young children often cannot describe their pain. Work through the steps in order rather than jumping straight to a scan.
- Clinical history: ask about the sequence of pain, anorexia, vomiting and fever, and note the timeline in hours rather than days.
- Examination: look for right lower quadrant tenderness, rebound, and the psoas and obturator signs, and note whether the child looks toxic.
- Blood tests: a raised total leucocyte count, neutrophilia and C-reactive protein support the diagnosis but do not confirm it, and a normal count does not exclude it.
- Score: the Alvarado or Paediatric Appendicitis Score grades the risk, with a low score making appendicitis unlikely and a high score favouring imaging and surgical review.
- Imaging: graded compression ultrasonography first, with CT of the abdomen when ultrasound is equivocal, weighing radiation carefully.
- Decide: surgical consultation for appendicectomy, or antibiotics and observation in selected cases, with perforation as the key risk to watch.
Where the exam tries to catch you
Appendicitis vignettes often hide the diagnosis behind vague symptoms or a reassuring laboratory value.
- Trap: dismissing a toddler with fever and generalised abdominal pain as viral gastroenteritis. Correct: appendicitis is atypical in young children and perforates earlier, so imaging should be considered early.
- Trap: relying on the Alvarado score alone in a child. Correct: the Alvarado score was derived in adults, whereas the Paediatric Appendicitis Score was designed specifically for children.
- Trap: taking a normal white cell count as excluding appendicitis. Correct: a normal count occurs in a sizeable minority of cases, so clinical and imaging assessment still decides.
Frequently asked questions
Which score was designed specifically for children with appendicitis?
The Paediatric Appendicitis Score, also called Samuel's score, was designed specifically for children with suspected appendicitis. It combines clinical and laboratory features, and it complements the adult Alvarado score, which was derived in adults.
What is the first-line imaging for appendicitis in children?
Graded compression ultrasonography is the first-line imaging for suspected appendicitis in children. A non-compressible appendix with a diameter over 6 mm supports the diagnosis, and the test avoids ionising radiation.
Why do infants with appendicitis perforate more often?
Infants with appendicitis perforate more often because their appendix is thin-walled, their omentum is underdeveloped and they cannot localise or describe pain well. Diagnosis is therefore often delayed, which allows perforation to occur.
What finding suggests an appendicular abscess?
A palpable right iliac fossa mass with persistent fever and raised inflammatory markers, often after several days of illness, suggests an appendicular phlegmon or abscess. Ultrasound or CT confirms the collection before management is planned.
What is the classic pain sequence in appendicitis?
Classic appendicitis begins with periumbilical colicky pain that migrates to the right lower quadrant over several hours, with anorexia and vomiting. Migration is one component of the Alvarado score, so it contributes directly to the score.