["An association between cow's milk hypersensitivity (CMH) and gastro-oesophageal reflux disease (GERD) in childhood has been reported in the past decade.", "To assess whether biopsies from the upper gastrointestinal tract of children with cow's milk sensitive GERD have a specific allergic inflammatory pattern, and to compare two different techniques for measuring inflammatory cells in gastrointestinal biopsies.", "GERD was diagnosed by means of endoscopy and oesophageal pH monitoring. Hypersensitivity to cow's milk was determined by an elimination diet and cow's milk challenge. Allergic inflammatory cells in upper gastrointestinal biopsies were identified by immunohistochemistry and their numbers were assessed by two different methods-counting the number of cells/high power field and using the computerised Cast-Grid system.", "Cow's milk sensitive GERD was identified in 10 of 17 children with severe GERD (median age, 7.8 years). Biopsies from children with endoscopic oesophagitis had significantly increased numbers of mast cells and T cells. No differences in the number of eosinophils, mast cells, or T cells were found between children with CMH and those with primary GERD. Several differences were found between the two different histological quantification methods."] Is eosinophilia in the upper gastrointestinal tract a characteristic feature in cow 's milk sensitive gastro-oesophageal reflux disease . Measurement by two methodologies?