Von Willebrand disease - Skin
Disorders of hemostasis may be categorized as:
- Primary hemostasis – Involving VWF, platelets, and the endothelium. Lack of these factors results in prolonged bleeding, petechiae, or easy bruising.
- Secondary hemostasis – Involving the coagulation cascade and the 13 factors. Lack of these factors can result in more profound bleeding, such as hemarthroses, or bleeding into cavities and muscles.
VWF is an important part of initial hemostasis and binds to the damaged endothelium and activates platelets. Additionally, VWF carries factor VIII, and a deficiency in VWF results in a relative deficiency in VIII (although it is quantitatively normal).
There are three classifications of von Willebrand disease (VWD):
- Type 1 – A quantitative reduction (most common)
- Type 2 – Abnormal VWF
- Type 3 – Absent VWF (with many subtypes)
Young patients with VWD may first present to the emergency room or pediatrician with bruising, and this can cause suspicion of physical abuse. Thus, while appropriate action regarding the suspicion of abuse is important, the workup can be challenging. Unusual bruising or injury, where abuse is denied, should involve consideration of a bleeding disorder, and it may also involve referral to a hematologist to exclude a clotting disorder.
For more information, see OMIM.
D68.0 – Von Willebrand's disease
128105004 – von Willebrand disorder
- Infectious – Viral, streptococcal, meningococcemia. Meningococcemia usually acutely erupts with petechiae throughout the body and quickly forms vesicles, bullae, and pustules that then become stellate purpura with a central dusky or grey hue. Viral includes a nonspecific widespread erythematous eruption where the patient does not look toxic.
- Drug related – Erythematous macules and papules on the trunk that spread to the extremities. Rash blanches under pressure and is usually found 7-14 days after exposure to a medication.
- Erythema nodosum – Erythematous, tender, deep-seated nodules and plaques, 2-5 cm, located on anterior shins, usually in women.
- Immunoglobulin A vasculitis (formerly Henoch-Schönlein purpura) – Scattered palpable purpura distributed over ankles, knees, and buttocks bilaterally. May have associated abdominal or joint pain.
- Capillary hemangioma – Telangiectatic, vasoconstricted patch. Not present at birth, but arises within a few months and has deep red papules that involutes after a year.
- Blue-gray spot (congenital dermal melanocytosis, formerly known as Mongolian spot) – Blue-gray spots that are evenly pigmented, located over the sacrococcygeal region, and tend to occur in infants or children of Asian or African descent. Generally present at birth.
- Prominent facial veins
- Ehlers-Danlos – Hypermobile joints; thin, soft, doughy skin that recoils. May have characteristic "fish mouth"-like scars or "cigarette paper"-like scars over extremities.
- Hypermobility syndrome
- Scurvy – Corkscrew hairs, perifollicular purpura, bleeding gums, and broad areas of purpura and ecchymosis may be present.
- Subconjunctival hemorrhage – Blood-red area of the conjunctiva that can cover a few millimeters or the whole eye. Associated with minor trauma, sneezing, eye rubbing, or straining.
- Coining – Cultural practice showing linear erythematous patches with petechiae and ecchymosis, usually in parallel.
- Cupping – 4- to 6-cm circular burns with central ecchymosis and petechiae.
- Nonaccidental trauma (NAT) – It can be difficult to differentiate among a true coagulopathy, physical abuse, and accidental trauma. Accidental trauma usually occurs over bony prominences in mobile children, including knees and shins. The size of accidental bruises are small, between 10 and 15 mm. Signs concerning for NAT include bruises in infants <9 months (as they are not cruising), ecchymosis on neck, face, torso, arms, buttocks, genitalia, lips, or earlobes or evidence of an imprint from a weapon. An imprint in the shape of a hand, fingers, belt mark, iron, or electrical wires is more predictive of child abuse. Belt or electrical wire marks may be evenly spaced or curvilinear/arcuate. In NAT bruises also tend to be grouped and larger. If fractures or subconjunctival hemorrhages or subdural hematomas are present and/or the parents have an inconsistent story, abuse is much more likely.
- Ink, paint, or dye marks
- Self-induced bruising