Duodenal histopathology and laboratory deficiencies related to bone metabolism in coeliac disease

Coeliac disease (CD) is a chronic immune-mediated small intestine enteropathy precipitated by gluten in genetically predisposed individuals. Adult presentation is often atypical and malabsorption of vitamins and minerals is common, with a consequent disturbance of bone metabolism. We aim to evaluate laboratory deficiencies related to bone metabolism and the relationship between severity of histological damage and degree of bone mass loss at diagnosis of CD.

A retrospective cross-sectional study of 176 adult coeliac patients was carried out. All patients fulfilled the histopathological criteria for CD. Biochemical data were analysed (calcium/phosphate/alkaline-phosphatase/vitamin D/parathormone). Duodenal histology was classified according to the Marsh classification. Bone mass density (BMD) at the lumbar and femoral regions measured by dual X-ray absorptiometry. A P-value of less than 0.05 was considered significant.

No correlation was found between the presence of gastrointestinal symptoms and the Marsh histopathological stage (P>0.05). Vitamin D deficiency was most common (44.5%), whereas only 5.7% had hypocalcaemia. Calcium was lower (P<0.05) and parathormone was higher (P=0.01) in patients with Marsh III. These patients had lower lumbar T-score (P<0.05). Although low BMD occurred in all age groups, most osteoporotic patients were aged 45-49 years (81.8%). A multiple regression analysis showed that the Marsh histopathological stage could be a predictor of lower lumbar BMD (r=0.322, B=-1.146, P<0.05).

Laboratory deficiencies and decreased BMD could be severe and unrelated to the presence of gastrointestinal symptoms. At diagnosis, the Marsh histopathological stage could predict the occurrence of low BMD, which carries a risk of developing into osteoporosis. In coeliac patients older than 30 years, evaluation of bone biomarkers and dual X-ray absorptiometry examination should be considered.