Which of the following conditions may not impair the clotting system?

• A. Hemophilia
• B. Vitamin K deficiency
• C. Sickle cell anemia
• D. Disseminated intravascular coagulation

Answer: (D)

Understanding how clotting can be impaired helps distinguish these conditions. Hemophilia involves a deficit in a clotting factor, so the coagulation cascade can’t proceed properly and bleeding risk rises. Vitamin K deficiency reduces production of several important clotting factors, leading to weaker clot formation as well. Disseminated intravascular coagulation triggers widespread clotting that uses up clotting factors and platelets, ultimately leading to bleeding because the body's resources for clotting are exhausted. Sickle cell disease, by contrast, does not inherently cause a deficiency or defect in the clotting factors themselves. It mainly causes red blood cell sickling and vaso-occlusion, and while it can be associated with changes in coagulation, it does not directly impair the enzymatic clotting cascade in the same way as the others. So, this condition may not impair the clotting system.