# Von Willebrand Disease

> Von Willebrand disease for NEET-PG Paediatrics, covering types, the mucocutaneous bleeding pattern, laboratory diagnosis and when desmopressin is used.

- Canonical URL: https://prepelephant.com/topics/neet-pg/paediatrics/von-willebrand-disease
- Exam / course: NEET-PG · Subject: Paediatrics
- Publisher: PrepElephant (https://prepelephant.com) — Prepared and reviewed by the PrepElephant Academic Review Team
- First published: 2026-10-08
- Last updated: 2026-10-08
- Reference basis: Nathan and Oski's Hematology and Oncology of Infancy and Childhood; Williams Hematology
- How to cite: "Von Willebrand Disease", PrepElephant, https://prepelephant.com/topics/neet-pg/paediatrics/von-willebrand-disease

## Direct answer

Von Willebrand disease is the commonest inherited bleeding disorder, caused by a quantitative or qualitative defect in von Willebrand factor, which links platelets to exposed subendothelium and carries factor VIII. It produces mucocutaneous bleeding such as epistaxis, gum bleeding and menorrhagia, usually with a normal platelet count. Desmopressin, which releases stored von Willebrand factor, is first-line for type 1 and many type 2 patients, but it fails in type 3.

## What you must remember

- **Inheritance:** types 1 and 2 are mostly autosomal dominant, while type 3 is autosomal recessive and the most severe form.
- **Type 1:** partial quantitative deficiency; the commonest and mildest type.
- **Type 2:** qualitative variants, including 2A (loss of large multimers), 2B (gain of function with platelet binding), 2M (defective platelet binding with normal multimers) and 2N (factor VIII binding defect).
- **Type 3:** near-absent von Willebrand factor and very low factor VIII, with severe bleeding that can resemble haemophilia A.
- **Bleeding pattern:** mucocutaneous bleeding, unlike the deep joint and muscle bleeding typical of haemophilia.
- **Laboratory:** reduced von Willebrand factor antigen and ristocetin cofactor activity; the bleeding time is now considered unreliable.

## A stepwise diagnostic and treatment pathway

Diagnosis needs a consistent set of assays, because levels rise with stress and pregnancy, and a single normal result does not exclude the disorder.

1. **Screen the bleeding history:** epistaxis, gum bleeding, heavy periods, post-procedure haemorrhage and family history of similar bleeding.
2. **Check routine tests:** complete blood count, prothrombin time and activated partial thromboplastin time, which may be prolonged in type 3 or with low factor VIII.
3. **Measure von Willebrand factor:** antigen, ristocetin cofactor activity and factor VIII activity, ideally repeated when the child is well.
4. **Characterise the type:** multimer analysis and ristocetin-induced platelet aggregation separate type 2A and 2B from other variants.
5. **Test desmopressin response:** measure factor levels before and after a dose; a rise indicates response, and fluid restriction is needed because of hyponatraemia.
6. **Plan treatment:** desmopressin for type 1, tranexamic acid for mucosal bleeding, and von Willebrand factor concentrate for type 3 or non-responders.

## Where the exam tries to catch you

Von Willebrand vignettes separate students who know the types from those who only know the name.

- **Trap:** using a normal bleeding time to exclude the disorder — **Correct:** the bleeding time is unreliable, so von Willebrand factor levels must be measured.
- **Trap:** using desmopressin in type 3 — **Correct:** there is no stored von Willebrand factor in type 3, so replacement concentrate is needed.
- **Trap:** giving desmopressin to type 2B without caution — **Correct:** it can provoke thrombocytopenia in type 2B, so platelet counts are monitored.
- **Trap:** attributing heavy periods in a teenager to hormones alone — **Correct:** von Willebrand disease is a common cause of menorrhagia and should be screened for.

## Frequently asked questions

### What is the commonest inherited bleeding disorder in children?

Von Willebrand disease is the commonest inherited bleeding disorder, more common than haemophilia, and it is usually autosomal dominant. Its mucocutaneous pattern makes it easy to miss in a child with epistaxis or heavy periods.

### How does desmopressin work in von Willebrand disease?

Desmopressin stimulates release of stored von Willebrand factor from endothelial cells, raising factor levels in type 1 and many type 2 patients. It is ineffective in type 3, where von Willebrand factor is virtually absent.

### Which test best confirms von Willebrand disease?

Von Willebrand factor antigen and ristocetin cofactor activity are the core tests, with factor VIII activity added to assess the complex. A reduced ratio of ristocetin cofactor to antigen helps identify qualitative type 2 variants.

### What is the characteristic bleeding pattern of von Willebrand disease?

Von Willebrand disease causes mucocutaneous bleeding, such as nosebleeds, gum bleeding, bruising and heavy menstrual bleeding, with a normal platelet count. Deep joint and muscle bleeding is more typical of haemophilia.

### Why does desmopressin need caution in type 2B von Willebrand disease?

Desmopressin can precipitate thrombocytopenia in type 2B because the abnormal von Willebrand factor binds platelets more readily. Platelet counts are monitored whenever desmopressin is given to such children.