We appreciate the thoughtful response by Villanacci et al. to our manuscript. We agree that proper specimen procurement (by gastroenterologists) and orientation (by histotechnicians) is vital to the accurate diagnosis of microscopic colitis, as it is to many diagnoses. (This has been formally evaluated in the context of assessing for histologic gastric atrophy [1].)

We can fortunately report that in our experience, gastroenterologists tend to sample both the right and left colon, as they recommend. For the second point, however, optimum embedding is not always achieved, particularly in busy (and potentially understaffed) laboratories. Our retrospective analysis did not account for sampling adequacy or quality of biopsy embedding, preferring to focus on using actual, previously handled cases from our archives. For real-time cases where features diagnostic of microscopic colitis appear equivocal, pathologists cannot of course request additional tissue from the gastroenterologist, but they can consider the possibility of re-embedding the biopsy tissue, or perhaps cutting additional levels in the hopes of obtaining a more clear picture of the overall changes present within the specimen.