Esophagitis in infants. Morphometric histological diagnosis and correlation with measures of gastroesophageal reflux.

To assess the incidence of histological esophagitis in infants less than 2 yr old with symptoms of gastroesophageal reflux, 35 infants were studied with esophageal suction biopsy and pH probe monitoring. Intraepithelial and lamina propria inflammatory cells, basal cell layer thickness, and papillary height were quantitated. Distal esophageal sections from infant sudden death trauma victims were used to provide normal morphometric control values. The upper limit of normal for each of the four histological parameters of esophagitis was defined as the mean plus three standard deviations. The values thus derived were similar to established adult normal values. Seventy-seven percent of the patients had at least one abnormal histological parameter (intraepithelial eosinophils or neutrophils, thickened basal cell layer, or increased papillary height) and were thus considered to have esophagitis. These measures of esophagitis all correlated well with each other, providing an internal consistency to the histological interpretation. Lamina propria eosinophilia correlated highly with intraepithelial eosinophils (r = 0.98) and was found to have a sensitivity of 41% and specificity of 89% for diagnosing histological esophagitis, defined as abnormality of any of the four histological parameters. Ninety-three percent of the patients with histological esophagitis had significant reflux as determined by pH probe monitoring. However, there was generally poor correlation between the severity of the esophagitis as quantitated by morphometric parameters and severity of the reflux as measured by pH monitoring. Esophageal suction biopsies, which provide adequate specimens for morphometric interpretation, are appropriate for diagnosing reflux esophagitis in infants.