has characteristic has characteristic Childhood onset gastritis pediatric collagenous gastritis https://github.com/monarch-initiative/mondo/issues/6743 https://www.malacards.org/card/pediatric_collagenous_gastritis childhood-onset collagenous gastritis MONDO:0044624 GARD:0021998 Orphanet:487809 MEDGEN:1805938 UMLS:C5680109