Question

A 3 year old boy had suden onset of gross, hematuria, with no history of previous bleeding. The patient’s paternal aunt was a “bleeder”. The patient had been taking antibiotics and aspirin for an upper respiratory infection. His admitting Coagulation Studies showed:

Bleeding time:                        Greater than 10 min

Remainder of the profile:     Normal

Additional Reference lab results:

            --Markedly abnormal platelet adhesiveness test

            --Borderline Factor VIII level

            --Platelet aggregation studies showed the effect of aspirin

                        (abnormal secondary aggregation)

1. What is the most probable diagnosis?

2. What additional tests should be performed to confirm the diagnosis?

Answer 1

1. The most probable diagnosis is Von Willebrand disease. This is the most common hereditary blood clotting disorder. The usual cause is an inherited abnormal gene that controls von Willebrand factor, a protein that plays a key role in blood-clotting. When you have low levels of this protein or it doesn't work as it should, platelets cannot stick together properly, nor can they attach themselves normally to the blood vessel walls when an injury has occurred. This causes excessive uncontrolled bleeding.

2. The additional investigations to be done to confirm the diagnosis are:

• Von Willebrand factor antigen
• Ristocetin cofactor activity
• Factor VIII clotting activity
• Von Willebrand factor multimers