Case Based Pediatrics For Medical Students and Residents
Department of Pediatrics, University of Hawaii John A. Burns School of Medicine
Chapter IX.2. Abdominal Pain
Walton K.T. Shim, MD
June 2002

Return to Table of Contents

This is a 6 year old female presenting with a 2 day history of crampy abdominal pain. The pain is located in the upper mid-abdomen and is associated with anorexia, nausea and four episodes of green vomitus. She appears to be weak and her parents noticed a decrease in urination. There is no history of diarrhea, trauma, fever or coughing. She has not passed any stools for the two days that she has been ill.

Her past history is significant for an appendectomy one year ago. Her family history is negative for other family members with similar problems.

Exam: VS T 37.0, P110, R 12, BP 100/60. She is alert and subdued. She moves without difficulty but cries episodically because of crampy pain. Her mucous membrane are sticky. Her eyes are sunken. Her neck is supple. Her heart and lungs are normal. She has a RLQ (McBurney's point) scar. She has moderate abdominal distention with hyperactive bowel sounds, peristaltic rushes and borborygmi with generalized mild tenderness. She has no inguinal hernias and her external genitalia are normal. A rectal exam finds no stool or mass. Her back is non-tender. Her skin turgor is decreased, but her overall color and perfusion are good.

CBC: WBC 14.0, Hgb 16, Hct 48, Na 132, K 3.0, Cl 90, bicarb 30. Urinalysis: SG 1.030, no pyuria or hematuria. Abdominal series radiographs show distended ladderlike small bowel with large air/fluid levels and no large bowel gas. No calcifications. Lung bases are normal.

Impression: Small bowel obstruction secondary to adhesions; dehydration, metabolic alkalosis and hypovolemia.

Abdominal pain is a common symptom of childhood. Its importance lies in differentiating the vast majority self-limited causes of pain from those few conditions that may be life threatening. In the latter category are those conditions that lead to a diagnosis of an "acute abdomen," usually leading to surgical intervention. Examples of these in children are most commonly acute appendicitis followed by incarcerated inguinal hernias, bowel obstruction, traumatic injury, ovarian torsion, pancreatitis, and biliary disease. Further complicating the diagnosis is the young child's relative inability to communicate and his/her inability to evaluate the abstract concept of pain.

In general, it is helpful to classify abdominal pain into two large categories: 1) pain originating in a hollow viscus, and 2) pain originating in a solid organ or the peritoneum.

Hollow viscus pain such as that of an the obstructed ureter, intestine, and gallbladder is colicky or spasmodic in nature. It coincides with the peristaltic waves of the organ as it attempts to overcome the distal obstruction such as ureteral or cystic duct stone or a fecal bolus in constipation. These waves or cramps are exactly what we experience with early acute appendicitis and gastroenteritis and are somewhat ameliorated by writhing and massage.

On the other hand peritoneal and solid organ pain such as caused by infection or trauma is aggravated by motion caused by coughing, abdominal compression, and walking. It is usually unrelenting or steady.

The search for the cause of abdominal pain is a good example of both inductive and deductive reasoning. In gathering data, a complete history and physical examination should suggest a disease process, a hypothesis or diagnosis (induction) which in turn should suggest a search for confirmative or corroborative data to strengthen or disprove the diagnostic hypothesis (deduction).

In evaluating the case above using inductive reasoning, the symptoms of crampy mid-abdominal pain, bilious vomiting, and history of prior abdominal surgery, suggest a hypotheses of bowel obstruction. If it is intestinal obstruction, an abdominal series should show an obstructive pattern (deduction).

It could be ureteral colic but this is uncommon in children and there is no blood in the urine indicating that a ureteral stone is unlikely. It could be biliary colic but this is rare in children and the pain distribution is not that of biliary pain. It could be a gynecological problem but this girl is prepubertal, and ovarian torsion frequently presents in the lower quadrant and radiates to the anterior thigh.

With a bowel obstruction, there may be bowel infarction. If there is gangrene by deduction there should be an elevated WBC, absent bowel sounds, marked tenderness, and localization of pain. Since none of these findings is present, bowel compromise (infarction) is unlikely.

The following data suggest dehydration by induction: urine specific gravity of 1.030, history of infrequent urination, sticky (dry) mucous membranes, sunken eyes and weakness.

In addition to peritoneal and hollow viscus pain, there is pain of neural origin. Nerve root compression by spinal cord tumors are rare but must be suspected if no other cause for the discomfort can be found and if the pain distribution is that of a dermatome. There should be no tenderness to palpation, but there may be hypesthesia.

Inflammation of the pleura from a pneumonic process in the distribution of the lower thoracic nerves is not an infrequent cause for referred abdominal pain and should be a reason for auscultation of the chest in a search for pneumonia or pleurisy. The abdominal series includes the lung bases and should be noticed when evaluating abdominal films. Lower lobe pneumonia can frequently be seen in the lung portions of an abdominal series, and it is very frequently overlooked since the clinician is usually focusing on the abdominal structures.

Diabetic acidosis, lupus erythematosus, porphyria, and other systemic illnesses may cause pain and inflammation of the serous surfaces (serositis). Some non-surgical causes of abdominal pain are lactose intolerance, inflammatory bowel disease, intussusception (sometimes requires surgery), Henoch-Schonlein purpura, ascariasis and acute gastroenteritis. Of help in the diagnosis of many of the non-surgical diseases is their chronicity or recurrence. Of course, the first occurrence of the symptoms is always more difficult to sort out.

Constipation is a common cause of chronic, recurrent and acute abdominal pain of varying degrees of severity. Relief after an enema is characteristic, but some cases are associated with more serious GI pathology, since the presence of constipation does not rule out the presence of something else, such as appendicitis.

As with most rules of thumb or generalizations there are exceptions that the clinician should keep in mind. One of these is that appendiceal pain always occurs in the right lower quadrant since the appendix is located there. However, since it is 6-13 cm long, its inflamed tip may come to rest anywhere in a radius of 6-13 cm from its base. This means that tenderness may be produced in the right upper quadrant, the midline, or in the suprapubic region. Similarly, if it is retrocecal so that it has no contact with peritoneum, the child may not exhibit severe tenderness. In its retrocecal position however, it may rest on the right psoas muscle and cause pain with active right hip flexion. If it lies on the right ureter, hematuria and pyuria may be produced.

Malrotation of the cecum may lead to all sorts of additional presentations for acute appendicitis. However, the astute clinician should keep in mind that rare things occur rarely and that when you hear hoof beats they are most likely horses and not gazelles or camels (in North America anyway).

The examiner of children must realize that most children wish to please, so that a child brought in the middle of the night to the hospital may feel obligated (obliged) to its adult caregivers and nighttime physicians to show cause for such concern. Thus, when asked if their tummy hurts, they may be inclined to answer affirmatively to justify the trip and trouble.

Similarly, older teenage boys with a macho image to uphold, may hesitate to admit pain and/or tenderness. It is a useful ploy to engage the child/teen in conversation about his or her dog, siblings or other familiar childhood topics while depressing the abdominal wall. Any true tenderness will be confirmed or refuted by involuntary guarding or its absence. A useful technique is to ask the child to cough while asking what he or she feels. This ploy will direct attention away from the abdomen but almost always elicits peritoneal discomfort if present.

Persistence and constancy of a sign heightens its importance in diagnosis. Tenderness should be reproducible. Sensory innervation of the intestines is via the ninth through eleventh thoracic nerve roots. Consequently pain from the intestines due to stretching is appreciated as originating from the mid-abdomen until an inflammatory process localizes it in the dermatome of the parietal peritoneum. There are several areas of referred pain which, when present, may suggest a specific entity. Radiation of flank pain into the groin and ipsilateral scrotum or labium suggests ureteral colic. Lower quadrant pain radiating to the anterior thigh should suggest torsion of the ipsilateral ovary and tube. A point of pain in either shoulder indicates subdiaphragmatic irritation from blood or pus. Right upper abdominal pain radiating around to the back suggests biliary tract involvement but epigastric pain radiating through to the back suggests a pancreatic origin.

The use of specific diagnostic tests should be guided by the clinical examination and evaluation. They should not be a substitute for such evaluation and should not precede the clinical examination since the clinical appraisal may obviate the need for additional tests. Plain film radiographs, ultrasound, computerized axial tomography (CAT scan), magnetic resonance imaging (MRI), and contrast studies may aid in the evaluation of abdominal pain but should be used judiciously. The flat and upright plain film radiographs can be particularly useful in recognizing small bowel obstruction, ileus, abnormal calcifications and lower lung pathology.

In summary, acute abdominal pain is a common childhood complaint. In most instances it usually passes without much interruption of the events of daily living. However, abdominal pain can also signal severe illness leading to serious morbidity and death if not attended to. Thus, separating the chaff from the wheat is extremely important. Persistence of pain associated with vomiting, dehydration and signs of inflammation should not be ignored, but should stimulate a thorough evaluation. The use of both inductive reasoning to formulate a hypothesis for the cause of the pain followed by deductive reasoning to confirm the hypothesis is the basis for identifying the correct diagnosis.


1. True/False: Surgical causes of abdominal pain are much less common than non-surgical causes.

2. True/False: Predicting a finding from a hypothesis is called deductive reasoning.

3. What characteristics differentiate hollow viscus from solid viscus and peritoneal pain?

4. Pain from distended intestines is appreciated in what area?

5. Where is the pain of urogenital origin referred?

Related x-rays

Challenging abdominal pain case: Yamamoto LG. Abdominal Pain with a Negative Abdominal Examination. In: Yamamoto LG, Inaba AS, DiMauro R (eds). Radiology Cases In Pediatric Emergency Medicine, 1994, volume 1, case 3. Available online at:

Challenging abdominal pain case: Yamamoto LG. Persistent Abdominal Pain. In: Yamamoto LG, Inaba AS, DiMauro R (eds). Radiology Cases In Pediatric Emergency Medicine, 1994, volume 1, case 4. Available online at:

Challenging abdominal pain case: Halm B. Right Lower Quadrant Pain in a 13-Year Old Female. In: Yamamoto LG, Inaba AS, DiMauro R (eds). Radiology Cases In Pediatric Emergency Medicine, 1996, volume 4, case 8. Available online at:

Abdominal pain with right sided calcifications: Yamamoto LG. Right-Sided Abdominal Pain in a 10-Year Old. In: Yamamoto LG, Inaba AS, DiMauro R (eds). Radiology Cases In Pediatric Emergency Medicine, 1996, volume 5, case 18. Available online at:


1. Cope Z. The Early Diagnosis of the Acute Abdomen, 14th edition. 1974, London: Oxford University Press.

2. Raffensperger JG. The Acute Abdomen in Infancy and Childhood. 1970, Philadelphia: J.B. Lippincott Company.

Answers to questions

1. True

2. True

3. Crampy (hollow viscus) versus steady (solid viscus and peritoneal).

4. Mid-abdomen

5. Flank, groin and ipsilateral scrotum or labium

Return to Table of Contents

University of Hawaii Department of Pediatrics Home Page