| Age group | Cause of pain | Diagnostic clues | 
|---|
| 0-2 years | Pyloric stenosis* | Jet-like vomiting; age 2-8 weeks | 
 | Invagination* | Paroxysmal pain, some diarrhoea, "meat water" and empty rectal ampulla at DRE | 
 | Incarcerated hernia* | Reposition is neither easy nor successful | 
 | Testis torsion* | Testicular pain, visible swelling (but intra-inguinal torsion is possible in retention) | 
 | Gastroenteritis | Diarrhoea or vomiting are the first and dominant symptoms | 
 | Otitis media | Ear status | 
 | Urinary tract infection or other serious infection | Fever and vomiting without evident diarrhoea; urine test | 
| 3-11 years | Appendicitis* | Transfer of pain, pin-point tenderness, jumping test | 
 | Dolores abdominis NUD | The most common entity; important to differentiate from appendicitis | 
 | Mesenterial lymphadenitis | Clues do not differ from those of appendicitis | 
 | Gastroenteritis | Diarrhoea at onset, non-existent or slight tenderness on palpation | 
 | Constipation | History, hard stools; pain is often severe | 
 | Pneumonia | Cough, findings on auscultation, chest radiograph | 
 | Sinusitis | Local symptoms, ultrasonography, sinus radiograph | 
 | Tonsillitis | Inspection of the pharynx | 
 | Urinary tract infection | Urine test | 
 | Henoch-Sch�nlein purpura | Petechial rash | 
| >11 years | Appendicitis* | See above | 
 | Gastroenteritis | See above | 
 | Salpingitis | Only in the sexually active | 
 | Ovarian cyst | May burst at exertion | 
 | Urinary tract infection | Urine test |