After tonsillectomy, a 9 year old child is having continuous bleeding. Bleeding time and PTT are prolonged. Platelet count and PT are normal. What is your diagnosis
**Core Concept**
The child's symptoms suggest a disorder of primary hemostasis, given the prolonged bleeding time and normal platelet count. This indicates a problem with platelet function or vessel wall integrity.
**Why the Correct Answer is Right**
The prolonged bleeding time and normal platelet count suggest a deficiency in von Willebrand factor (vWF), a crucial protein involved in platelet adhesion to the damaged vessel wall. vWF is a carrier protein for factor VIII and facilitates platelet aggregation. The child's symptoms are consistent with von Willebrand disease (VWD), a common inherited bleeding disorder. The normal PTT and PT indicate that the coagulation cascade, excluding the intrinsic pathway, is intact. However, the prolonged bleeding time points towards a problem in the initial steps of hemostasis.
**Why Each Wrong Option is Incorrect**
**Option A:** This option would be incorrect as it does not explain the prolonged bleeding time and normal platelet count.
**Option B:** This option would be incorrect as it does not account for the prolonged bleeding time and would not explain the child's symptoms.
**Option C:** This option would be incorrect as it does not explain the prolonged bleeding time and normal platelet count.
**Option D:** This option would be incorrect as it does not account for the prolonged bleeding time and would not explain the child's symptoms.
**Clinical Pearl / High-Yield Fact**
Von Willebrand disease is the most common inherited bleeding disorder, with a prevalence of approximately 1 in 100 individuals. It is caused by a deficiency or dysfunction of von Willebrand factor, leading to impaired platelet adhesion and aggregation.
**Correct Answer: B. von Willebrand disease**