Introduction: Untreated coeliac disease may induce malabsorption of many nutrients. It may also induce vitamin K deficiency, which causes prolongation of the prothrombin time. The aim of the present study was to evaluate the prevalence and associations of prolonged prothrombin time in a series of coeliac adults.
Methods: We carried out a cross-sectional analysis of data collected on 390 adults with untreated coeliac disease diagnosed from January 1997 to December 2000. Prolonged prothrombin time was defined as INR > or = 1.4.
Results: A prolonged prothrombin time was found in 72 coeliac patients (18.5%). Parenteral vitamin K therapy was required in 5.6% of patients. Patients with prolonged prothrombin time had significant lower values of haemoglobin, iron, proteins, cholesterol and serum aspartate transaminase, and significantly higher prevalence of diarrhoea, weight loss, abdominal pain and low bone mineral density in comparison with patients with normal prothrombin time. However, low bone density was present in 11.6% of patients with normal INR. A prolonged prothrombin time was only found in a few patients with subclinical coeliac disease (0.9%).
Conclusions: Data indicate that the prevalence of prolonged prothrombin time is about 20% in a large series of adult untreated coeliac patients. A prolonged prothrombin time was significantly related to all the markers of severe malabsorption, including low mineral density. Our suggestion is that vitamin K related proteins may also play a role in determining or worsening calcium homeostasis disorders in coeliac disease. The very low prevalence of coagulation disorders in subclinical coeliac disease indicates that there is no need to screen for coeliac disease in patients with isolated coagulation disorders.