Abdominal pain, acute in children

Probability diagnosis

Infant ‘colic’ (2–16 weeks)

Gastroenteritis (all ages)

Mesenteric adenitis

Serious disorders not to be missed

Infection:

• acute appendicitis (mainly 5–15 years)

• pneumonia (esp. right lower lobe)

• pyelonephritis

• peritonitis

Cancer:

• colon cancer (rare)

Other:

• intussusception (peaks at 6–9 months)

• bowel obstruction

• coeliac disease

• strangulated inguinal hernia

Pitfalls (often missed)

Child abuse

Constipation

Torsion of testes

Lactose intolerance

Peptic ulcer

Infection: mumps, tonsillitis, pneumonia (esp. right lower lobe), EBM, UTI, hepatitis

Adnexal disorders in females (e.g. ovarian)

Rarities:

• Meckel diverticulitis

• Henoch–Schönlein purpura

• inflammatory bowel disease

• sickle crisis

• lead poisoning

Masquerades checklist

Diabetes mellitus

Drugs

UTI

Psychogenic consideration

Important cause

Key history

Differentiate the severe problems demanding surgery from the non-surgical ones. About 1 in 15 will have a surgical cause for pain. The causes are often age specific so a family history is important.

Key examination

• Note general appearance, vital signs and oral cavity

• Abdominal examination: inspection, auscultation, palpation and percussion (in that order)

• Rectal examination is mandatory: look for constipation including impacted faeces

• Examine lungs, especially if lower lobe pneumonia suspected

• Consider gentle abdominal palpation with a soft toy

Key investigations

• Rule out urinary infection with urinalysis. Blood, protein and leucocytes may all be present with acute appendicitis. Nitrites are more specific for UTIs

• FBE/ESR/CRP

• Scanning according to findings

• Imaging (e.g. oxygen/barium enema) as appropriate

Diagnostic tips

• Consider mesenteric adenitis in a flushed febrile child with an URTI or tonsillitis.

• Vomiting occurs in at least 80% of children with appendicitis and diarrhoea in about 20%.

• A pale infant with severe colic and vomiting indicates acute intussusception.