Owing to the characteristic Warthin-Finkeldey giant cells found in hyperplastic mucosa-associated lymphoid tissue, it has been emphasized that pathologists can make a diagnosis of measles from appendectomy specimens even in the prodromal stage before diagnostic rashes develop. However, to date, those reported cases of measles-related appendicitis have dealt with the histologic features of the prodromal stage and we found no reports in the English literature describing the histopathologic findings of appendicitis during the full-blown stage of measles. Here, we describe 2 cases of measles-related appendicitis that show contrasting histologic features according to stage, one discovered during the prodromal stage and the other occurring during the full-blown stage. This report describes heretofore unreported histopathologic findings of measles-related appendicitis observed during the full-blown stage of the infection and highlights histopathologic changes caused by replication of the virus in different compartments of the same organ during the course of infection.