Significance of lymphoid follicles and aggregates in gastric mucosa of children

This study was designed to evaluate the significance of gastric lymphoid follicles (LF) and aggregates (LA) in children with and without Helicobacter pylori (HP) infection. All 605 antrum biopsies performed during 1994 were reviewed and classified according to the presence or absence of inflammation, LE or LA. HP was searched with a DiffQuik stain in all biopsies showing gastritis, LF, or LA. Gastritis was diagnosed in 80 biopsies (16 with LE 18 with LA and 46 without LA or LF). Identification of HP in these biopsies was as follows: (a) cases with LF: 12/16; (b) cases with LA: 3/18; (c) cases without LF or LA: 8/46. The biopsies without gastritis had a higher frequency of LA (65/525) than of LF (2/525). HP was not identified in any case without gastritis. The presence of LF with histologic gastritis had the strongest correlation with HP (R = 0.5, p < 0.00001). LF with gastritis had a positive predictive value of 75% for HP and the absence of LF had a negative predictive value of 82.8% (sensitivity 52%; specificity 92%). LA with gastritis had no significant correlation with HP. From these results we conclude that lymphoid follicles should be distinguished from lymphoid aggregates. Lymphoid follicles can rarely be present in an otherwise normal gastric mucosa; however, they are more frequently found in cases of gastritis and are strongly associated with HP infection. Lymphoid aggregates are not significantly associated with HP infection and may be a component of the normal gastric lymphoid tissue.