BELLEVUE, WASH. – If a child has had abdominal pain for 4-6 weeks without constipation, it’s almost always functional abdominal pain.
That "somewhat bold thesis" explains nearly all childhood abdominal pain, Dr. Tyler Burpee said at the annual meeting of the North Pacific Pediatric Society.
Functional GI disorders, although frequently misdiagnosed, account for 2%-4% of general pediatric visits and more than half of consultations with pediatric gastroenterologists. These patients are suffering, and have lower quality-of-life scores compared with patients who have asthma or migraines, studies have shown.
Dr. Tyler Burpee
When patients with functional GI disorders don’t meet criteria for functional dyspepsia, irritable bowel syndrome, or abdominal migraine, they fall into the catch-all diagnostic subcategory of functional abdominal pain, the most common type in children. Diagnostic criteria include continuous or episodic abdominal pain occurring at least weekly for at least 2 months with no evidence of an inflammatory, anatomical, metabolic, or neoplastic process that explains the symptoms.
When parents (and even some physicians) hear the diagnosis of functional abdominal pain, they commonly misinterpret it to mean, "It’s all in your head," said Dr. Burpee, a pediatric gastroenterologist at St. Luke’s Children’s Hospital, Boise, Idaho.
He explains to parents and the child that the transmission of pain from the gut to the brain is incredibly complex, with more nerves in the gut than in the brain or the spinal cord. Functional abdominal pain "means that there’s not something we can see, like an ulcer, but there’s something abnormal happening in the gut," he said.
There’s no cookie-cutter work-up for these patients because their symptoms and characteristics vary so widely, he said. Physicians often order an ultrasound of the abdomen or pelvis, but there’s no evidence that this is helpful in diagnosing functional abdominal pain. The predictive value of blood tests has not been well studied.
Esophagogastroduodenoscopy (EGD) should not be ordered unless the patient exhibits "alarm symptoms," Dr. Burpee said, which can include involuntary weight loss or growth failure, dysphagia, frequent vomiting, chronic and severe diarrhea, nocturnal symptoms (especially bowel movements), persistent right upper quadrant or right lower quadrant pain, or rectal bleeding without constipation. A recent study of 301 patients found that negative EGD results do not improve outcomes with functional GI disorders (Clin. Pediatr. 2011;50:396-401).
There are many useful treatments for functional abdominal pain in children, but antibiotics probably are not on that list. "I don’t think antibiotics are ready for prime time," he said.
Cognitive-behavioral therapy (CBT) and hypnotherapy have the most positive evidence behind them, but other helpful treatments may include peppermint oil, probiotics, the alteration of parenting techniques, and possibly tricyclic antidepressants, placebo pills, or biofeedback.
Parents who tried to distract their child’s attention from abdominal pain made the child feel better than did parents who offered solicitous attention ("Where is the pain? How much does it hurt?") in a prospective study of 223 children with and without functional abdominal pain. In fact, children’s symptom complaints nearly doubled under conditions of parent attention, and were reduced by half under conditions of parent distraction. However, parents in the study feared that the distraction strategy would do more harm than giving attention (Pain 2006;122:43-52).
A separate study of CBT randomized 200 children with functional abdominal pain and their parents to three sessions of either education (the control group) or CBT for training in relaxation, modifying responses to illness/wellness, and altering dysfunctional thoughts about symptoms. Decreases in pain and GI symptoms were significantly greater in the CBT group during 6 months of follow-up. Parents in the CBT group were significantly more likely to decrease their solicitous responses to the child’s symptoms (Am. J. Gastroenterol. 2010;105:946-56).
Hypnotherapy appeared to be astoundingly successful in a study that randomized 51 patients to standard medical therapy or six 50-minute sessions of gut-directed hypnotherapy over a 3-month period. Decreases in the frequency and intensity of abdominal pain were significantly greater in the hypnotherapy group. Rates of clinical remission (defined as at least an 80% decrease in pain intensity and frequency scores) were 25% in the control group and 85% with hypnotherapy – which is "incredible success" in functional abdominal pain, Dr. Burpee said.
The caveat is that the study used one very experienced hypnotherapist, but Seattle Children’s Hospital has begun treating functional abdominal pain and Dr. Burpee has worked with several individual hypnotherapists, both with "incredible success," he said. Hypnotherapy is safe, he added.
Another benign therapy showing promise is peppermint oil. A 2-week period of treatment decreased pain severity by 19% in patients who were randomized to placebo, and by 75% in patients randomized to take enteric-coated peppermint oil capsules (0.2 mL) three times per day, a study of 42 children with irritable bowel syndrome found (J. Pediatr. 2001;138:125-8). The study has limitations, but "it’s a good proof of concept" that also may apply to functional abdominal pain, Dr. Burpee said.