Episodic pain in a school-aged child

Key Points

The boy is flipping through a coloring book as his mother paces the room. She lunges to greet you, stifling your apologies for the wait with a stack of papers, x-ray reports, lab printouts, and other miscellaneous pieces of a medical record.

She begins to tell you about her son, a 5-year-old with a three-month history of episodic abdominal pain. The pain is difficult for him to describe, but she interprets the pain as crampy and periumbilical. It occurs during normal daily activities, and is not associated with anything in particular. These episodes occur one to five times daily, and last for 30 to 60 seconds. The onset is abrupt, and causes the child to stop his activities and hold his abdomen.

She is very concerned because these episodes have been increasing in frequency over the past month. They even occur overnight sporadically, waking him from sleep. He occasionally vomits with these episodes. He has no food triggers, and there is no history of nausea, diarrhea, constipation, gross blood in his stool, abdominal distention, dysuria, change in urine color, or change in stool color or consistency. He has had no weight loss, cough, upper respiratory symptoms, headache, photophobia, or rashes. He has no travel history, recent camping, well water, or any other unusual exposures.

You listen to her story, all the while observing the child happily coloring in his book. You appreciate the mother's concern, but he appears quite normal and healthy. You hope that the physical exam will guide your assessment, but you are not optimistic.

On exam the boy is pain-free and playful, well developed and growing normally. His weight is 56 lbs (25.6 kg). He is afebrile; blood pressure, 98/57 mm Hg; heart rate, 101 bpm; respiratory rate, 24 bpm. The patient has a small bandage on his forehead covering a healing abrasion.

He has one small café au lait spot, but no other skin lesions. His mucous membranes are moist; lungs are clear to auscultation; he has no murmurs. The abdomen is soft and nontender with normal bowel sound and no guarding or rebound. His genital and rectal exams are normal with no masses or hernias; his stool is Guaiac-negative with no skin tags or fissures. He has a normal musculoskeletal and neurologic exam. The remainder of his physical exam is unremarkable. With no solid clues from the child's physical exam, you excuse yourself to review his medical record.

That's a RAP

Based on the mother's description, and your evaluation, the child meets the criteria for recurrent abdominal pain (RAP): He's between 4 to 16 years old, with at least three episodes of pain over at least three months affecting his normal activity, with no organic cause in sight. You know that recurrent abdominal pain can have many causes, so you approach the differential diagnosis by dividing it based on associated symptoms.^1,2 While all RAP patients by definition will have pain, some will have changes in BMs, others will have dyspepsia, and others will just have intermittent recurrent pain. He appears to be in the latter group, with no associated upper or lower GI symptoms.

Even after having come to this conclusion, the differential is still broad² (see Table 1). Such intermittent recurrent pain could have gastrointestinal causes, such as functional abdominal pain, fecal impaction, inflammatory bowel disease (IBD), and partial small bowel obstruction. Or infectious causes such as Giardia, metabolic causes like acute intermittent porphyria. Or urinary causes such as ureteropelvic junction (UPJ) obstruction and nephrolithiasis; neurologic causes such as somatization or abdominal migraines; or vascular causes such as mesenteric thrombosis or vasculitis.