Diagnosis of GERD

Despite the existence of internationally approved guidelines, the diagnosis of gastroesophageal reflux (GER)-disease remains difficult (Rosen et al. J Pediatr Gastroenterol Nutr. 66:516-54, 2018). GER-disease is generally considered a clinical diagnosis. However, differentiation between physiologic GER, functional regurgitation, and GER-disease in infants and between functional heartburn, hypersensitive esophagus, rumination syndrome, symptoms of esophageal dysfunction, and GER-disease in older children can be difficult based on clinical grounds alone. In addition, some patients present with extra-esophageal problems such as chronic respiratory disease, chronic cough, or ENT problems. Many diagnostic tests have been proposed, but none of them can truly be seen as a gold standard. Upper gastrointestinal endoscopy with biopsies can show erosive esophagitis and Barrett’s esophagus and is able to differentiate between reflux esophagitis and eosinophilic esophagitis, but cannot show or exclude non-erosive GER-disease. In theory, 24-h pH-impedance testing allows for detecting all GER events and establishing a temporal association between individual GER events and symptoms. However, no true normative data are available and its analysis can be difficult, especially in severe cases with low impedance baselines. Additionally, the statistical calculation of an association between GER and symptoms is dependent on sufficient symptoms and their adequate objective monitoring. A trial with acid suppression can be helpful to diagnose acid-related disease in older children, but not in patients where weakly acidic GER is predominant. The placebo effect of such a trial carries the risk of chronic over-treatment in functional heartburn. Several less invasive tests have been studied, but their diagnostic value is, as yet, limited.