Variability in small bowel histopathology reporting between different pathology practice settings: impact on the diagnosis of coeliac disease.
Source: J Clin Pathol. 2011 Nov 12. Celiac Disease Center at Columbia University Medical Center, Division of Digestive and Liver Diseases, Department of Medicine, Columbia University, New York, New York, USA.
Background and Aims - Coeliac disease (celiac disease) diagnosis requires the detection of characteristic histological alterations of small bowel mucosa, which are prone to interobserver variability. This study evaluated the agreement in biopsy interpretation between different pathology practice types.
Methods - Biopsies from community hospitals (n=46), university hospitals (n=18) and commercial laboratories (n=38) were blindly assessed by a pathologist at our institution for differences in histopathology reporting and agreement in diagnosis of celiac disease and degree of villous atrophy (VA) by κ analysis.
Results - Agreement for primary diagnosis was very good between this institution and university hospitals (κ=0.888), but moderate compared with community hospitals (κ=0.465) or commercial laboratories (κ=0.419). Diagnosis differed in 26 (25%) cases, leading to a 20% increase in celiac disease diagnosis after review. Among those diagnosed with celiac disease by both institutions (n=49), agreement in degree of villous atrophy (VA) was fair (κ=0.292), with moderate agreement between the authors and commercial laboratories (κ=0.500) and fair with university hospitals (κ=0.290) or community hospitals (κ=0.211). The degree of VA was upgraded in 27% and downgraded in 2%. Within different Marsh score categories, agreement was poor (κ<0.0316) for scores 1 and 2, both missed at other centres, and fair or moderate for scores 3a and 3b. Information regarding degree of VA and intraepithelial lymphocytosis was lacking in 26% and 86% of reports and non-quantifiable descriptors, eg, 'blunting' or 'marked atrophy' were prevalent.
Conclusions - celiac disease-related histological changes are underdiagnosed in community-based hospitals and commercial pathology laboratories. Because incorrect biopsy interpretation can cause underdiagnosis of celiac disease, greater celiac disease awareness and uniformity in small bowel biopsy reporting is required among pathologists.