Question

Why is prothrombin time value obtained prior to intestinal biopsy?

Answer 1

basically in any deep seated invasive interventional procedure we must rule out too mant things such as...

viral profile and triple serology like Hbs Ag, anti HCV and status of HIV infectivity....routein blood count and differential count, any bleeding diasthesia, bleeding time and clotting time assesment, Coagulation profile study like PT,INR and aPTT etc..

now why PT is obtained prior to intestinal biopsy....

1stly... intestinal biopsy is usually carried out for confermation of IBD like celiac disease, whipple's disease, rule out malignant trensformation in GIT, etc...

as in preexisting celiac disease with celiac crisis and whipples disease .....PT is prolonged....

this is basically linked with relation of Prothrombine time and Vitamine K...

A site of Vit K absorption is from the proximal intestine (in a form of  phylloquinone)... and vit k is needed for the clotting factors espacially factors II, VII, IX, X...

and factor II, VII, IX, X activity is denoted by prothrombine time...

so ultimately... in intestinal disease....vit K absorption hampers.... leads to altered coagulation factors  II, VII, IX, X...... these coagulation factors alters prothrombine time BY INCREASING IT....AND ultimately increasing PT leads to increasing bleeding risk in any invasive procedure like biopsy.. and as in the intestinal disorder there are more chances of prolongation of PT so risk of bleeding is more in intersinal biopsy......