Question

Which of the following is true about a platelet function defect (qualitative platelet disorder)?

• A. Normal platelet count with prolonged bleeding time
• B. Thrombocytopenia with prolonged bleeding time
• C. Normal bleeding time with normal platelet number
• D. Normal platelet count with decreased bleeding time

Hint:

A qualitative defect leaves the count untouched but cripples primary haemostasis, so which screening test lengthens?

Answer 1

The Correct Option is A

Step 1: Define the disorder. A platelet function (qualitative) defect means the platelets are present in adequate numbers but do not work properly, as in Glanzmann thrombasthenia, Bernard-Soulier syndrome, uremia, or aspirin use.
Step 2: Recall what bleeding time measures. Bleeding time reflects platelet number AND platelet function (primary haemostasis). If platelets do not adhere or aggregate normally, bleeding time is prolonged even when the count is normal.
Step 3: Apply to the count. Since the defect is functional and not numerical, the platelet count remains normal.
Step 4: Evaluate options. Normal count with prolonged bleeding time fits a qualitative defect exactly. Thrombocytopenia (low count) describes a quantitative disorder. Normal bleeding time with normal count would be a healthy person. Decreased bleeding time is not a recognised finding.
Answer: Normal platelet count with prolonged bleeding time (option A).