Frequently Asked Questions

CMTC stands for Cutis Marmorata Telangiectatica Congenita — a rare, congenital disorder of the blood vessels in the skin. Children are born with a purple- or dark-blue, net-like pattern on the skin, often on an arm, leg or trunk. The medical name describes the appearance: cutis marmorata means “marbled skin”, telangiectatica refers to the visible dilated blood vessels, and congenita means present at birth.

In most children the patches gradually become less visible — often within the first five years of life — but in some they remain lifelong. CMTC can also coincide with other features such as a length difference between arms or legs, glaucoma, or other vascular peculiarities. Regular medical follow-up is therefore important.

Want more technical and medical information? Read our extensive CMTC information page in the Pedia.

CMTC-OVM is a global, non-profit patient organisation, founded by parents who themselves faced the challenge of finding a diagnosis and the right care. Today we connect patients, parents, healthcare providers and researchers. Our activities focus on four core tasks:

Peer support — Through our online community, family days and international conferences, we bring together people who share the same experience. Recognition and shared experience are often just as valuable as medical information.

Information — We provide reliable, accessible information about CMTC and related conditions through our Pedia, brochures, videos and webinars. For patients, parents, young adults and healthcare professionals.

Advocacy — We represent patients to researchers, policymakers and healthcare professionals. In several countries we have active advocates who stand up for access to diagnosis, care and recognition.

Scientific research — We stimulate and support genetic research and actively look for the causes of CMTC and related malformations. Our members can contribute to studies that shape the care of the future.

Although our name refers to CMTC, we support everyone affected by a rare vascular malformation. The abbreviation OVM literally stands for “Other Vascular Malformations” — we are there for the whole group.

Conditions you can turn to us for include:

Klippel-Trenaunay syndrome, Sturge-Weber syndrome, PROS (PIK3CA-Related Overgrowth Spectrum), capillary malformation, lymphatic malformation, AV malformation, venous malformation, CLOVES syndrome, stork bite, port-wine stain, hemangio-endothelioma, Tufted angioma, NICH/RICH hemangiomas, and more.

A complete overview with information per condition — written in accessible language — can be found in our Pedia of conditions.

Membership is completely free. On our registration page you can create an account in just a few minutes. You don’t need to have a formal diagnosis — if you are involved with someone affected by a vascular malformation, or if you are looking for information because you have suspicions, you are equally welcome.

As a member you get:

• Access to protected content on the website, including member-only articles and videos;
• Membership of the online community, where you can connect with other patients and parents;
• Our regular newsletter in English and Dutch;
• The right to use our personal medical advice service;
• Invitations to family days, member conferences and webinars;
• The opportunity to share your own personal story — and help others.

Yes. Members of CMTC-OVM can use our personal medical advice service. Your question will be answered confidentially by experts in the field of vascular malformations — physicians, specialists and experienced peers we have connected to our organisation over the years.

This is particularly valuable because CMTC and related conditions are so rare that many general practitioners and even specialists have limited experience. Through our service you get a second opinion or direction from someone who truly understands these conditions.

More information and the request form can be found on the Medical advice page. Important: this advice is intended as a supplement to — not a replacement for — contact with your own treating physician. It is also not an emergency-care channel; for acute complaints please contact your GP or the emergency department directly.

CMTC-OVM is a non-profit organisation that runs entirely on volunteers and donations. We do not receive structural government funding, so every contribution helps us to continue research, events and information services.

You can contribute in several ways:

• Donate — one-off or recurring, large or small, every euro counts;
• Sponsor as a company or organisation;
• Become a volunteer — for example at events, with translations, editing or advocacy;
• Share your story or take part in research as a member.

Our policy plan and overviews of our sponsors and volunteers are public on the website. We believe transparency matters.

CMTC is currently considered a sporadic condition — meaning it usually appears for the first time in a family and is not clearly inherited from parent to child. CMTC most likely arises from a somatic mutation: a change in the DNA that occurs during embryonic development, in only a subset of cells. As a result, the chance of transmission to the next generation is very small.

However, science is moving forward. Genetic research into CMTC and related malformations (such as PROS, which involves the PIK3CA gene) has made major progress in recent years. CMTC-OVM actively stimulates this research and hopes that the exact genetic causes will be better understood in the coming years.

Do you have questions about heredity in a specific situation? We recommend discussing this with a clinical geneticist. Our medical advice service can help you further.