You have a new patient!
An 18-month-old boy is brought to the emergency department (ED) by his parents due to lethargy that has persisted for the last few hours. He is a term-born child with no significant antenatal history or pre-existing medical conditions. The child had been well until five days ago when he experienced a case of viral gastroenteritis. His feeding and urine output were adequate until about three hours ago, after which he began experiencing progressive episodes of crying, accompanied by vomiting and abdominal distension. There was no diarrhea or dark-colored stools noted.
During the triage assessment, the child appeared unsettled but was afebrile, with other vital signs within age-appropriate ranges. There were no rashes observed on his body, and there were no blood-stained stools in his diaper.
What do you need to know?
Importance
Abdominal pain is a common reason for children to present to the Emergency Department (ED) and represents up to 5% of all presentations in some institutions [1]. The most common causes are non-surgical, and at times it may be difficult to arrive at a specific diagnosis before discharge. However, it is crucial to identify causes of abdominal pain that require early surgical intervention, particularly when a clear diagnosis cannot be made before discharge. Pay special attention to red flags such as lethargy (in neonates and infants), severe pain or irritability, bilious emesis, abdominal distension, peritoneal signs, or signs of sepsis.
The differential diagnoses (DDx) for abdominal pain vary with age groups. In younger children who cannot express themselves, reliance on parental history and a thorough physical examination is essential. Blood investigations and radiology may not be helpful, especially in early presentations, making serial examinations and observation more valuable. Additionally, remember that pain from other sites can be referred to the abdomen, particularly testicular pain.
Epidemiology
Pediatric abdominal pain is a common reason for emergency department (ED) visits, accounting for approximately 12% of all visits [2]. The median age of children presenting with abdominal pain is around 9 years, with a higher incidence in girls [2, 3]. Non-specific abdominal pain is the most prevalent diagnosis, affecting 40% of children, followed by functional abdominal pain (FAP), constipation, and viral infections [2, 4]. Despite the high prevalence of abdominal pain, a significant portion of children (62.7%) are discharged directly from the ED, while 37.3% require admission [3]. However, follow-up studies indicate that about 50% of children report ongoing pain after discharge, highlighting the chronic nature of abdominal pain [3].
Pathophysiology
The sensation of abdominal pain is transmitted either by somatic or visceral afferent fibres [5]. Visceral pain from the visceral peritoneum is poorly localised and is often referred to its corresponding dermatome on the abdominal wall. If you recall the human embryological development of abdominal organs, the organs developing from the foregut (oesophagus to the second part of the duodenum) have pain referred to the T8 dermatome (i.e., the epigastric area), those developing from the midgut (from the third part of the duodenum to the proximal two-thirds of the transverse colon) have pain referred to the T10 dermatome (i.e., the umbilical area), and those from the hindgut (distal one-third of the transverse colon to the rectum) refer to the T12 dermatome [6].
Somatic pain from the parietal peritoneum is more localised. Thus, any abdominal condition that progresses to involve the parietal peritoneum will result in the patient complaining of migrating pain. In unfortunate situations where this advances to bowel rupture or peritonitis (i.e., surgical abdomen), the patient will exhibit signs of peritonism. You can observe this in the history of appendicitis, where the pain initially starts in the periumbilical region and migrates to the right lower quadrant.
Referred pain also occurs due to the convergence of visceral and somatic pathways in the spinal column. Two examples of referred pain are diaphragmatic irritation leading to pain at the shoulder tip due to the convergence of visceral and somatic pathways at C4, and somatic pain from pneumonia leading to T10–11 pain perceived in the lower abdomen [5].
Initial Assessment and Stabilization
Airway & Breathing
- Provide supplemental oxygen and attach an SPO2 probe.
Circulation
- Assess for signs of sepsis, shock, dehydration, or the need for IV pain relief. If any of these are present, obtain IV access.
- If in shock, administer an IV crystalloid fluid bolus of 20 ml/kg. Reassess and repeat if necessary.
- If sepsis is suspected, obtain blood cultures via IV and administer Ceftriaxone 50 mg/kg (up to 2 g) AND metronidazole 10 mg/kg (up to 500 mg). Follow your local antibiotic guidelines.
- If not in shock but dehydrated, initiate IV maintenance therapy.
- Provide adequate pain control. Consider IV morphine 0.05–0.1 mg/kg or IV fentanyl 1 μg/kg.
Disability
- Check a point-of-care glucose level in sick children. Consider hypoglycemia or DKA as alternative diagnoses.
Exposure
- Examine the abdomen for abdominal distension, masses, or peritonism. Involve the surgical team early. This is further discussed in the physical examination section.
- Always examine the genitals (e.g., for testicular torsion or strangulated hernia).
Medical History
In history, focus on the following:
Age of the child – DDx varies with the child’s age and the initial presenting complaints. Remember that neonates and infants often present with lethargy, irritability, poor feeding, or vomiting.
Age | Surgical diagnoses | Medical diagnoses |
Birth to 3 months |
|
|
3 months to 3 years |
|
|
3 years and above |
|
|
Timing of the symptoms:
a. Intussusception may follow a bout of diarrhoeal illness.
b. Appendicitis typically presents as a gradual onset of pain migrating from the periumbilical area to the right lower quadrant.
Pain character – Episodic pain is observed in intussusception and mesenteric adenitis.
Blood in stool – Consider necrotizing enterocolitis, intussusception, and volvulus.
Bilious or non-bilious vomiting – Bilious vomiting is indicative of obstruction below the ampulla of Vater. It is a classic presentation of malrotation with midgut volvulus and may also present in incarcerated/strangulated hernia or Hirschsprung disease with enterocolitis. Non-bilious vomiting is classically associated with pyloric stenosis.
Associated symptoms – A rash may be present in Henoch-Schönlein purpura. Fever, when associated with inflammation (e.g., appendicitis) or the translocation of gut bacteria, may lead to sepsis.
Oral intake, urine output (UOP), and activity levels – These are important. Escalate to a senior opinion for admission or IV hydration if these parameters are below 50% of the child’s baseline.
Other relevant history:
- Past medical and surgical history, including birth history such as prematurity in neonates and infants.
- Social history, especially when suspecting non-accidental injury.
- Menstrual and sexual history in adolescent females.
Physical Examination
A good history and physical examination are very important in managing undifferentiated paediatric abdominal pain patients. You must perform an abdominal examination, including genitourinary and inguinal exams, especially in children who cannot express themselves. Remember that you may find little or no helpful clinical signs initially; however, serial examinations may reveal the condition as it evolves. A digital rectal examination is very rarely indicated, and even then, it should ideally be limited to once and performed by the surgeon [7].
Also, remember that these are children, and they may intentionally exhibit voluntary guarding during palpation if they are distressed, regardless of the cause. Covering the art of paediatric abdominal examination is beyond the scope of this chapter, but consider providing analgesia, employing distraction techniques, and building good rapport with the child.
Please ensure that your patients receive adequate analgesia before the examination, as this will make the patient cooperative, simplify the examination, and highlight clinical signs.
General Examination
- Assess general appearance and determine whether the child looks ill or well.
- Record temperature and other vital signs.
- Observe for pallor and jaundice. Obtain an accurate body weight.
- Observe the child walking to the examination bed or within the department. Children with peritonism may refuse to walk or walk slowly with a stooped posture.
- Observe for signs of pain when coughing or jumping.
Inspection
- Look for asymmetry and abdominal distension. Abdominal distension is less pronounced in higher bowel obstructions (e.g., midgut volvulus) than in lower bowel obstructions.
- Check for purpuric patches, which are diffusely seen in Henoch-Schönlein purpura (HSP).
Palpation
- Feel for any masses, tenderness, and peritonism. Remember that classic presentations of masses (e.g., an olive-shaped mass in pyloric stenosis or a sausage-shaped mass in intussusception) may not be palpable in the emergency department, as the condition may be intermittent or in an early stage.
- Palpable bowel loops are classically associated with necrotizing enterocolitis.
- Pyloric stenosis typically presents with a non-tender abdomen.
- For most surgical causes, peritoneal findings can occur late. Consider the possibility of septic shock in a drowsy child presenting with abdominal tenderness on palpation.
Other Systems to Examine for Abdominal Pain [7]
- Respiratory: Assess for signs of basal pneumonia.
- ENT: Consider upper respiratory tract infections (URTI), tonsillitis, or adenopathy.
- Neurological: Rule out meningitis.
- Endocrine: Check blood glucose levels for diabetic ketoacidosis.
- Haematological: Look for pallor and lymphadenopathy.
- Dermatological: Look for rashes, particularly purpura/petechiae in Henoch-Schönlein purpura or zoster.
- Renal: Check for oliguria, haematuria, or hypertension in haemolytic uraemic syndrome.
In Our Patient
Physical Examination: Abdominal examination revealed an ill-defined mass in the right upper quadrant (RUQ). No pain was elicited on testicular palpation. No anal fissures or bleeding were noted on rectal examination. There were no signs of peritonism.
When To Ask for Senior Help
Do not hesitate to contact your seniors if you are concerned about your patient. The points below serve as a guide:
- An ill-looking patient.
- May require IV access for hydration or analgesia.
- Presence of peritoneal signs.
- Signs of sepsis.
- Bilious vomiting.
- Non-accidental injury or inconsistent history.
- Neonates (especially premature babies), if you lack experience in treating them.
- Parental anxiety.
Not-To-Miss Diagnoses
Pediatric abdominal pain is a common and complex issue in emergency departments, requiring a thorough differential diagnosis to identify serious underlying conditions [8]. The etiologies of abdominal pain vary by age, with infants (<2 years) commonly presenting with congenital anomalies, malrotation, and intussusception [8]. In children aged 2-5 years, appendicitis, gastroenteritis, and mesenteric adenitis are frequent diagnoses [9], while school-aged children (5-12 years) are more likely to experience constipation, urinary tract infections, and respiratory infections [8]. Adolescents (>12 years) are at risk for pelvic inflammatory disease, pregnancy-related issues, and ovarian torsion [8]. Common conditions such as appendicitis, constipation, and gastroenteritis are prevalent across different age groups, and non-gastrointestinal causes like pneumonia and acute asthma can also manifest as abdominal pain [10]. A comprehensive approach to diagnosis and management is essential to identify serious underlying conditions that may require urgent intervention.
Causes Requiring Early Surgical Intervention
- Peritonitis.
- Appendicitis.
- Testicular torsion.
- Incarcerated hernia.
- Necrotizing enterocolitis.
- Intussusception.
- Volvulus.
- Hirschsprung’s disease.
- Pregnancy or ectopic pregnancy in adolescent girls.
- Ovarian torsion in adolescent girls.
Medical Causes Not to Miss
- UTI in very young children (<5 years).
- Diabetic ketoacidosis.
- Sepsis.
- Haemolytic uraemic syndrome.
- Non-accidental injury.
Acing Diagnostic Testing
Remember that blood investigations are useful as supportive evidence for your history and physical examination, but they can be normal in surgical conditions. Avoid unnecessary venepuncture and/or IV cannulation in children unless the patient is sick or you are concerned about a not-to-miss diagnosis.
Bedside Tests
In sick patients, useful point-of-care tests include blood sugars, urine analysis, and capillary gas analysis. Blood sugars can indicate hypoglycaemia or DKA, and capillary gas analysis is useful for assessing lactate levels and metabolic acidosis. Urine analysis is helpful in confirming UTI, but ensure a proper uncontaminated sample has been collected [11]. Point-of-care ultrasound can be used for diagnosing intussusception, pyloric stenosis, or appendicitis.
Laboratory Tests
If venipuncture is performed, a full blood count, CRP, and renal function tests should be considered for all children. These tests may reveal evidence of inflammation or infection, as well as the extent of dehydration. You may also consider adding VBG and blood cultures for sicker children and tailor other testing depending on the patient (e.g., lipase for pancreatitis or beta HCG if pregnancy is suspected).
Imaging
Consider avoiding radiation or utilizing the lowest possible radiation dose. Ultrasound is the initial imaging modality of choice. In addition to point-of-care ultrasound, arrange an urgent departmental ultrasound if needed. If x-ray facilities are available, you can obtain a supine abdomen and upright/lateral decubitus view to look for free air. Computed tomography can be considered for life-threatening conditions when other modalities have failed. Magnetic resonance imaging is used in some parts of the world. It avoids radiation but may be time- or cost-prohibitive.
In Our Patient
- Point-of-care ultrasound (POCUS) showed a target sign over the abdominal mass.
- A diagnosis of intussusception was made.
Risk Stratification
Effective clinical decision rules (CDRs) for risk stratification of pediatric abdominal pain in emergency departments include the Pediatric Appendicitis Score (PAS) and the Pediatric Emergency Care Applied Research Network (PECARN) Pediatric Intra-Abdominal Injury rule. The PECARN rule is for trauma patients and out of the discussion in this chapter. The PAS is a valuable tool for assessing the likelihood of acute appendicitis in children presenting with abdominal pain, with studies showing that PAS scores correlate significantly with the severity of appendicitis [12]. A score below 4 has been found to rule out appendicitis, while higher scores indicate a higher risk of appendicitis [12]. Additionally, a recent Non-Specific Abdominal Pain (NSAP) Model has been developed to differentiate non-specific abdominal pain from organic causes, identifying key clinical predictors such as pain location and associated symptoms, and achieving a sensitivity of 71.8% [13]. These CDRs assist clinicians in identifying patients at risk for serious conditions, optimizing diagnostic processes, and reducing unnecessary interventions.
Management
Empiric and Symptomatic Treatment
Correct dehydration either orally in stable children or via IV in children who may need to be kept nil-by-mouth or are too sick to tolerate oral intake.
Consider keeping possible surgical patients nil-by-mouth. For bowel obstruction, consider inserting a nasogastric tube for gastric decompression.
Treat pain and distress.
- Consider non-pharmacological methods (e.g., examine the child on the parent’s lap).
Paracetamol
- Dose per kg: 15 mg/kg
- Frequency: Every 4 hours (q4h)
- Maximum Dose: 60 mg/kg/day
- Cautions/Comments:
- Ask for allergies.
- Check if/when the patient took acetaminophen at home.
Fentanyl
- Dose per kg: Intranasal 1.5 mcg/kg (for >12 months of age)
- Frequency: Every 15 minutes
- Maximum Dose: 3 mcg/kg
- Cautions/Comments:
- Not recommended for children <12 months of age.
- Divide the dose between nostrils.
- Consider alternative analgesia after the second dose.
Morphine
- Dose per kg:
- IV/Subcutaneous: 0.05–0.1 mg/kg
- Frequency: Every 2–4 hours
- Maximum Dose:
- For <1 month: 0.1 mg/kg every 4–6 hours
- For 1–12 months: 0.1 mg/kg every 2–4 hours
- For >12 months: 0.2 mg/kg every 2–4 hours
- Cautions/Comments:
- There is a chance of respiratory depression if the dose exceeds the recommended amount.
If sepsis is suspected, administer IV Cefotaxime and IV Metronidazole, or follow your local antibiotic guidelines.
Cefotaxime
- Dose per kg: IV 50 mg/kg
- Frequency: Every 12 hours
- Maximum Dose: 2000 mg
- Cautions/Comments:
- Can be given intramuscularly (IM) if IV access is difficult.
Metronidazole
- Dose per kg: IV 10 mg/kg
- Frequency: Every 8 hours
- Maximum Dose: 500 mg
- Cautions/Comments:
- Consider alternative analgesia after the second dose.
Piperacillin + Tazobactam
- Indication: For pseudomonal coverage in sepsis or hospital-acquired infections.
- Dose per kg:
- 2 months to 9 months: IV 80 mg/kg
- 9 months: IV 100 mg/kg
- Frequency: Every 8 hours
- Maximum Dose: 3000 mg
- Cautions/Comments:
- The dose is calculated based on the piperacillin component.
IV Fluids
- Use isotonic crystalloids. Avoid hypotonic solutions in the ED, except in rare circumstances as advised by paediatric nephrologists or paediatricians.
- For resuscitation, use 0.9% saline in 10–20 ml/kg boluses for all ages. You can repeat the boluses as necessary, but assess for signs of heart failure before administering each bolus.
- For IV maintenance, use a 0.9% saline and 5% dextrose combination if available. This can be prepared by mixing 450 ml of 0.9% saline with 50 ml of 50% dextrose. Alternatively, you can use 0.9% saline, Hartmann’s solution, or follow local guidelines.
When To Admit This Patient
If you are able to arrive at a diagnosis for these patients, then the disposition is often straightforward. On the other hand, patients with severe pain despite a negative physical examination and unclear diagnosis will require admission for observation and serial physical examinations.
If parents confirm that oral intake, UOP, and activity levels are less than 50% of the child’s baseline, the child should be admitted for IV hydration and observation. A short-stay unit may be suitable for such patients.
If there is a suspicion of non-accidental injury or any social circumstances (e.g., inability to return for review due to financial constraints or travel issues in rural areas), discuss admission with your senior doctor. Consider reviewing well-appearing neonates with seniors, especially if you think they can be safely discharged home.
Otherwise, well children with likely benign causes can be discharged home. Ensure that clear and close follow-up is arranged with their general practitioner or pediatrician.
Advise parents on when to return (e.g., if the child’s oral intake, UOP, or activity level reduces to less than 50% of their usual baseline, or if symptoms of sepsis or shock develop) and provide guidance on follow-up (either with their general practitioner or the nearest hospital with surgical capacity to review the child). If any outpatient radiological investigations are planned for the coming days, educate parents about the importance of attending these procedures as well.
Revisiting Your Patient
Our 18-month-old patient was confirmed to have an intussusception by point-of-care ultrasound.
On reviewing his history, the episodic crying and preceding viral illness are supportive of this diagnosis, and the lack of fever or other associated symptoms rules out most other diagnoses. The classical triad of abdominal pain, vomiting, and red-currant jelly stool described in patients is present in less than 50% of patients with the disease [14]. However, a better clue is that it is associated with lethargy even without signs of sepsis or dehydration.
His examination revealed normal vital signs, was afebrile, and had a soft, non-tender abdomen with an ill-defined lower abdominal mass, which also supports this diagnosis.
The ABCDE or primary survey did not show any other abnormalities.
He was kept nil-by-mouth, IV maintenance fluids were started, and an urgent surgical referral was made. Antibiotics were not needed at this stage as there was no other supportive evidence of associated sepsis. He was prescribed PRN pain relief with fentanyl and morphine but did not require any during the ED stay.
The surgical team reviewed him and took him to the operating theatre for air enema reduction.
Authors
Prassana Nadarajah
Listen to the chapter
References
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Reviewed and Edited By
Erin Simon, DO
Dr. Erin L. Simon is a Professor of Emergency Medicine at Northeast Ohio Medical University. She is Vice Chair of Research for Cleveland Clinic Emergency Services and Medical Director for the Cleveland Clinic Bath emergency department. Dr. Simon serves as a reviewer for multiple academic emergency medicine journals.
Arif Alper Cevik, MD, FEMAT, FIFEM
Prof Cevik is an Emergency Medicine academician at United Arab Emirates University, interested in international emergency medicine, emergency medicine education, medical education, point of care ultrasound and trauma. He is the founder and director of the International Emergency Medicine Education Project – iem-student.org, chair of the International Federation for Emergency Medicine (IFEM) core curriculum and education committee and board member of the Asian Society for Emergency Medicine and Emirati Board of Emergency Medicine.
