TY - JOUR

T1 - Observer variability in the histopathologic diagnosis of microscopic colitis and subgroups

AU - Fiehn, Anne-Marie Kanstrup

AU - Bjørnbak, Camilla

AU - Warnecke, Mads

AU - Engel, Peter Johan Heiberg

AU - Munck, Lars Kristian

N1 - © 2013.

PY - 2013/11

Y1 - 2013/11

N2 - The diagnosis of microscopic colitis (MC) is based on histologic findings and includes collagenous colitis (CC) and lymphocytic colitis (LC). Incomplete MC (MCi) denotes patients with chronic diarrhea and a normal endoscopy and morphological changes that do not completely meet the histologic criteria of LC or CC. The aim of this study was to investigate the intraobserver and interobserver agreement on the MC subtypes of CC, LC, and MCi and the ability to discriminate MCi from normal and inflammatory bowel disease/nonspecific reactive changes. A single hematoxylin and eosin-stained specimen from biopsies of the following 5 groups were randomly selected and blinded: CC, LC, MCi, inflammatory bowel disease, and normal. Three pathologists independently reviewed the specimens. The specimens were relabeled and reinterpreted 4 months later. Intraobserver and interobserver agreement was evaluated by κ statistics. κ values for intraobserver agreement were good for 5 diagnostic groups varying from 0.70 to 0.83 and very good when simplifying to only 3 diagnostic groups varying from 0.88 to 0.96, separating MC/MCi from non-MC. κ values for interobserver agreement varied from 0.60 to 0.75 for 5 diagnostic groups and 0.81 to 0.89 for 3 diagnostic groups. The study shows that the intraobserver and interobserver agreement is high for discriminating between MC/MCi and non-MC, whereas the ability to discriminate MCi from CC and LC is lower. A revision and consensus on the histologic criteria of the MC subtypes seem warranted.

AB - The diagnosis of microscopic colitis (MC) is based on histologic findings and includes collagenous colitis (CC) and lymphocytic colitis (LC). Incomplete MC (MCi) denotes patients with chronic diarrhea and a normal endoscopy and morphological changes that do not completely meet the histologic criteria of LC or CC. The aim of this study was to investigate the intraobserver and interobserver agreement on the MC subtypes of CC, LC, and MCi and the ability to discriminate MCi from normal and inflammatory bowel disease/nonspecific reactive changes. A single hematoxylin and eosin-stained specimen from biopsies of the following 5 groups were randomly selected and blinded: CC, LC, MCi, inflammatory bowel disease, and normal. Three pathologists independently reviewed the specimens. The specimens were relabeled and reinterpreted 4 months later. Intraobserver and interobserver agreement was evaluated by κ statistics. κ values for intraobserver agreement were good for 5 diagnostic groups varying from 0.70 to 0.83 and very good when simplifying to only 3 diagnostic groups varying from 0.88 to 0.96, separating MC/MCi from non-MC. κ values for interobserver agreement varied from 0.60 to 0.75 for 5 diagnostic groups and 0.81 to 0.89 for 3 diagnostic groups. The study shows that the intraobserver and interobserver agreement is high for discriminating between MC/MCi and non-MC, whereas the ability to discriminate MCi from CC and LC is lower. A revision and consensus on the histologic criteria of the MC subtypes seem warranted.

KW - Adult

KW - Aged

KW - Biopsy

KW - Colitis, Collagenous

KW - Colitis, Lymphocytic

KW - Colitis, Microscopic

KW - Colonoscopy

KW - Diagnosis, Differential

KW - Female

KW - Humans

KW - Male

KW - Middle Aged

KW - Observer Variation

KW - Reproducibility of Results

U2 - 10.1016/j.humpath.2013.06.004

DO - 10.1016/j.humpath.2013.06.004

M3 - Journal article

C2 - 24029708

VL - 44

SP - 2461

EP - 2466

JO - Human Pathology

JF - Human Pathology

SN - 0046-8177

IS - 11

ER -