Acute Abdominal Pain in Children
This causes significant worry in parents, often about the possibility of appendicitis. Some of the causes listed here (such as infant colic and constipation) can cause recurrent or chronic pain – this is a less common presentation, but one which, in children, still has a tendency to be presented as an ‘acute’ problem, either because of a perceived deterioration or parental anxiety. If managing children is within your scope of professional practice, more details about recurrent childhood abdominal pain can be found in the section of the same name.
Differential diagnosis
Common Diagnoses
- Constipation
- Infant Colic
- Gastroenteritis
- Urinary Tract Infection
- Appendicitis
Occasional Diagnoses
- Functional/IBS
- Stress/Malingering (e.g. School Problems, Bullying)
- Gastritis/GORD/Peptic Ulcer
- Mesenteric Adenitis
- CMPI
- Muscular Strain
Rare Diagnoses
- Inflammatory Bowel Disease
- Pneumonia
- Meckel’s Diverticulum
- Intussusception
- Coeliac Disease
- Intestinal Obstruction
- Testicular Torsion
- Henoch–Schönlein Purpura
- Sickle Cell Crises
- Lead Poisoning/Porphyria
- Renal Causes (Stones, Hydronephrosis)
- Diabetic Ketoacidosis
Ready reckoner
Key distinguishing features of the most common diagnoses
| Constipation | Infant Colic | Gastroenteritis | UTI | Appendicitis | |
|---|---|---|---|---|---|
| Child Under 6 Months | Possible | Yes | Possible | Possible | Possible |
| Recurrent | Possible | Yes | No | Possible | No |
| Child Acutely Unwell | No | No | Possible | Possible | Yes |
| Pain Constant | No | No | No | No | Yes |
| Urinary Symptoms | Possible | No | No | Yes | No |
Possible investigations
Likely: Urinalysis, MSU.
Possible: FBC, ESR/CRP, U&E, abdominal ultrasound.
Small Print: Coeliac screen, haemoglobinopathy screen.
- Urinalysis: Positive nitrite, leucocytes and/or blood support a clinical diagnosis of UTI; blood alone may indicate a stone (rare); urinalysis will also reveal sugar and ketones in diabetic ketoacidosis.
- FBC: May be iron deficiency in IBD.
- U&E: May occasionally be deranged in renal cause.
- Abdominal ultrasound: If renal causes suspected.
- Coeliac screen: Anti-endomysial and anti-gliadin antibodies suggest coeliac disease.
- Haemoglobinopathy screen: If sickle cell suspected.
Top Tips
- Be clear about safety netting – appendicitis may mimic gastroenteritis in the early stages. Share doubt and emphasise the need for reassessment if the pain becomes worse and constant, or if the general condition of the child deteriorates.
- Don’t forget to examine the groin and testicles – strangulated hernias and torted testicles are possible causes of this presentation, and the child may be too embarrassed to indicate the site of pain or swelling.
- Young children with less significant causes have a tendency to indicate the umbilicus as the site of pain. The further from the umbilicus the pain, the more you should consider an important cause.
- Recurrent ‘acute’ abdominal pain presenting on Mondays may indicate a school problem.
Red Flags
- Constant pain and the child being unable to straighten up because of discomfort suggest a surgical cause.
- Remember the possibility of sickling in the appropriate ethnic groups.
- Bear in mind that young children with pneumonia can present with abdominal pain – if unclear about the cause in an unwell child, check vital signs, features of respiratory distress and chest sounds.
- Consider intussusception in the infant with apparent abdominal pain associated with bouts of screaming and pallor.