Glomuvenous malformation (GVM)

What is a glomuvenous malformation (GVM)?

It is characterised by multiple venous malformations in the skin. GVMs can be pink in children, however, most are bluish-purple. They can be present at birth (congenital) or appear later in life. 

In most children, they first look like pink or blue raised lumps. They usually thicken over time and become darker blue and more uneven in texture, and grow proportionally with the child. They may swell when blood flow increases, for instance when crying, exercising or in hot weather. They do not lighten in colour when pressure is applied to the area. 

They can affect anyone of any age, although single GVMs tend to be more common in young adults.

How common are they?

They are rare, although there are no exact figures for the number of people diagnosed with them. GVMs are often inherited (64%). They are also more common in females than males but more research is needed to discover why.

Where do they occur?

They are common on fingers and toes.

How are they diagnosed?

A combination of tests and scans offer the best diagnosis. A skin biopsy can confirm the presence of glomus body cells and an MRI scan shows the malformation, its location and extent. 

Treatment

GVMs do not need any special care on a daily basis, however they can be painful if knocked or banged, or when there is an extreme change in temperature. Applying a cool compress can help. In contrast to venous malformations, avoid using elastic compressive garments which can aggravate pain. 

Treatment depends on size and location. One option is surgery, although this may not be possible for multiple or extensive glomuvenous malformations. 

Other common forms of treatment are: 

Laser treatment – to shrink the blood vessels using heat and light.

Sclerotherapy – to block the flow of blood through the vessels with a special substance. 

This site does not provide medical advice and is not a substitute for medical or professional care, and if you see a birthmark growing or changing significantly, see a specialist.