Which describes quantitative platelet defects?

Which describes quantitative platelet defects?

• A. Decreased production or increased destruction (quantitative) - drugs, virus, ITP, TTP, HUS, DIC
• B. Dysfunction (qualitative) - uremia, liver disease, DIC, drugs, myeloproliferative
• C. Vitamin K deficiency
• D. Renal failure

Answer: (A)

The main idea here is the difference between quantitative and qualitative platelet problems. Quantitative defects mean there are fewer platelets in the blood, so the platelet count is low. This happens when production is decreased or destruction is increased. Conditions like immune thrombocytopenia (ITP), thrombotic thrombocytopenic purpura (TTP), hemolytic uremic syndrome (HUS), and disseminated intravascular coagulation (DIC) fit this pattern because they either suppress production or consume or destroy platelets, leading to thrombocytopenia. Medications or viral infections can also cause platelet destruction, contributing to a lower platelet count. In contrast, a qualitative defect means the platelets are present in normal numbers but don’t function properly. That’s more related to issues like uremia or liver disease causing dysfunctional platelets, or drug effects that impair function, rather than a true drop in platelet count. Vitamin K deficiency affects clotting factors, not platelets themselves, so it’s a coagulation factor problem rather than a platelet defect. Renal failure often leads to platelet dysfunction (qualitative) rather than just a decreased count. So the description of decreased production or increased destruction—leading to a reduced platelet count—best fits a quantitative platelet defect.

The main idea here is the difference between quantitative and qualitative platelet problems. Quantitative defects mean there are fewer platelets in the blood, so the platelet count is low. This happens when production is decreased or destruction is increased. Conditions like immune thrombocytopenia (ITP), thrombotic thrombocytopenic purpura (TTP), hemolytic uremic syndrome (HUS), and disseminated intravascular coagulation (DIC) fit this pattern because they either suppress production or consume or destroy platelets, leading to thrombocytopenia. Medications or viral infections can also cause platelet destruction, contributing to a lower platelet count.

In contrast, a qualitative defect means the platelets are present in normal numbers but don’t function properly. That’s more related to issues like uremia or liver disease causing dysfunctional platelets, or drug effects that impair function, rather than a true drop in platelet count. Vitamin K deficiency affects clotting factors, not platelets themselves, so it’s a coagulation factor problem rather than a platelet defect. Renal failure often leads to platelet dysfunction (qualitative) rather than just a decreased count.

So the description of decreased production or increased destruction—leading to a reduced platelet count—best fits a quantitative platelet defect.