Reference — Hematology
Hemophilia & von Willebrand Disease Reference
The inherited bleeding disorders: a missing clotting factor (hemophilia) or a defective platelet-adhesion protein (von Willebrand). Two facts carry most questions — A = factor 8, B = factor 9, and vWD is the most common inherited bleeding disorder.
Educational use only. Factor replacement, dosing, and DDAVP use are provider-directed and individualized. This reference is an educational aid. This material supports nursing education and exam review. It is not medical advice and is not a substitute for clinical judgment, institutional policy, or medical direction. Always follow facility protocols and current provider orders.
The Three Disorders
| Disorder | Defect | Inheritance | Treatment |
|---|---|---|---|
| Hemophilia A | Factor VIII deficiency (the most common hemophilia, ~80%) | X-linked recessive | Factor VIII concentrate; DDAVP for mild cases |
| Hemophilia B | Factor IX deficiency (Christmas disease) | X-linked recessive | Factor IX concentrate (DDAVP does NOT help) |
| von Willebrand disease | von Willebrand factor deficiency/defect (impairs platelet adhesion + carries factor VIII) | Usually autosomal dominant | DDAVP first-line; vWF/factor VIII concentrate for severe types |
Presentation & Labs
Hemophilia (mostly affects males, carried by females): the hallmark is hemarthrosis — deep bleeding into joints causing pain, swelling, and over time joint damage. Also deep muscle bleeds, prolonged bleeding after trauma/surgery, and intracranial bleeding. Labs: prolonged aPTT with normal PT and platelet count; factor assay confirms.
von Willebrand disease (affects both sexes): more mucocutaneous bleeding — easy bruising, epistaxis, heavy menstrual bleeding, prolonged bleeding from cuts and after dental work. Because vWF carries factor VIII, severe cases also have a prolonged aPTT.
Treatment Essentials
Factor replacement is the cornerstone for hemophilia and severe vWD — given on demand for bleeds or prophylactically. DDAVP (desmopressin) releases stored factor VIII and vWF, so it helps mild hemophilia A and most vWD — but not hemophilia B (a factor IX problem). Antifibrinolytics (aminocaproic acid, tranexamic acid) help mucosal bleeding.
Avoid aspirin and NSAIDs (platelet inhibition), IM injections, and contact/high-impact activities. Apply pressure, ice, rest, and elevation for bleeds; for joint bleeds, give factor first, then rest and gentle rehabilitation.
NCLEX Pearls
- ✦Hemophilia A = factor VIII (8), Hemophilia B = factor IX (9); both X-linked recessive (mostly males).
- ✦Hemarthrosis (joint bleeding) is the hallmark of hemophilia; vWD is more mucocutaneous bleeding.
- ✦von Willebrand disease is the MOST COMMON inherited bleeding disorder.
- ✦DDAVP helps mild hemophilia A and vWD — but NOT hemophilia B.
- ✦Lab clue: prolonged aPTT with normal PT and platelets; confirm with factor assays.
- ✦No aspirin/NSAIDs, no IM injections; give factor before procedures and for joint bleeds.
Related Resources
Standards & sources
Fact-checked Jun 21, 2026This page is written to align with AABB (transfusion standards) · American Society of Hematology (ASH). It is an educational summary, not a citation of any single document — always verify specific doses, values, and protocols against current guidelines and your facility policy. How we source content →