BLAINE, WASH. — Several tests are available to help in the diagnosis of gastroesophageal reflux in infants and children, Dennis L. Christie, M.D., said at a conference sponsored by the North Pacific Pediatric Society.
These include extended barium swallows, scintiscan, ultrasound, extended pH monitoring, and endoscopy, said Dr. Christie of the University of Washington, Seattle.
▸ A barium contrast study, which may be accompanied by an upper GI study or a small bowel study, can be used to exclude anatomic abnormalities. This test can detect pyloric stenosis and other upper GI abnormalities, malrotation, hiatal hernia, vascular ring, and stricture.
Swallowing studies can be useful in evaluating nasopharyngeal reflux, aspiration, and esophageal peristalsis. But if you want a swallowing study, you'll have to be explicit, since radiologists no longer do this routinely.
▸ The technetium-99 scintiscan is not especially sensitive, but it can be useful in evaluating nonacid reflux, gastric emptying, and aspiration.
▸ Ultrasound is not used very commonly, but it can be useful in detecting pyloric stenosis.
▸ Extended pH monitoring is the preferred method for diagnosing gastroesophageal reflux. Typically, the pH probe is inserted intranasally and positioned just above the gastroesophageal sphincter. To determine the proximal extent of the reflux, some probes include two measuring devices, separated by 15–20 cm, allowing one to be positioned distally in the esophagus and the other proximally. Software converts the raw data to useful measures, including the percentage of the total time in which the pH is less than 4.0 (more than 5%–10% is abnormal), the total number of episodes, and the total number of episodes longer than 5 minutes.
Children with respiratory disease, for example, will not have esophagitis on biopsy but they do show frequent episodes of reflux—up to 100 episodes in 24 hours—that are very short lived. Children with tracheoesophageal fistula may have fewer episodes, but their episodes last much longer.
▸ Endoscopy is indicated to identify esophagitis and to establish a GER diagnosis in a patient with other negative studies but persistent symptoms. The esophagitis can be graded to plan adequate management, and endoscopy can also evaluate and exclude other upper GI pathology.
On biopsy, esophagitis is judged on the number of eosinophils and neutrophils present, the papillary height, and the basal cell thickness. The presence of any inflammatory cells indicates esophagitis, as does a papillary height greater than 53% and a basal cell thickness of greater than 25%.
Endoscopy also is useful fordiagnosing Barrett's esophagus, a precancerous condition that is rare, but not unheard of, in children, Dr. Christie said.
He described the case of a 5-year-old child with recurrent wheezing and frequent colds. The child had been diagnosed with reflux at 6 months of age, and with asthma more recently. He was brought to the emergency department after a bout of coffee-ground emesis.
A chest x-ray was normal, but given the child's history Dr. Christie suspected reflux. Dual-probe extended pH monitoring showed abnormal acid levels in the distal esophagus 8.9% of the time, with 396 episodes. The proximal esophagus showed abnormal acid levels 4.6% of the time with 66 episodes.
On endoscopy, the child was seen to have a wide-open gastroesophageal junction, severe mucosal erosion, and inflammation. Dr. Christie said that in such a child corrective surgery would likely be needed sooner or later.