Capillary malformation

In the body oxygen is transported through the blood vessels.

Oxygen-rich blood from the lungs is circulated by the heart to the brain and the rest of the body by large arteries. These arteries split and get smaller. At the place of destination (in the body) there should be a transfer taking the place of oxygen and nutrients. The blood flow may, of course, not be too fast, otherwise this transfer does not take place. Because the arteries so frequently have split and ever have narrowed blood eventually flows very slowly. The small vessels where this transfer of oxygen and nutrients takes place are the capillaries (capillaries). Eventually it becomes oxygen-poor blood again collected in small vessels which come back together and get bigger; the veins. The veins transport the oxygen-poor blood back to the heart.

A capillary malformation is a deviation from the capillaries. These vessels are then usually widened, making you the typical color of this skin condition. A capillary malformation is a slow-flow vascular malformation. Examples include the Wine Stain(Nevus flammeus), Stork bite and Cutis Marmorata Telangiectatica Congenita (CMTC).

Patient pathway

Understanding capillary malformations (Prof. Dr. Eulalia Baselga)

Capillary malformations are common skin conditions that appear as pink or red marks on the skin, often present from birth. These marks are caused by an abnormal arrangement of small blood vessels under the skin. While all these marks fall under the general term “capillary malformations,” they can look very different. In recent years, we have learned that these differences are due to mutations that occur in vascular cells during embryonic development. Depending on the timing of the mutation, the number of affected cells, the location of the mutation, and many other factors, capillary malformations can appear in various forms. Many genes can be involved, such as GNAQ, GNA11, PIK3CA, PIK3R1, KRAS, RASA1, EPHB4, and AKT3.

Differences in Appearance:

Capillary malformations can vary widely in how they look:

• Some are light pink, while others are dark purple.
• Some have smooth, indistinct edges, while others resemble geographical maps with well-defined borders.

Why Recognizing These Differences Matters

Although all vascular birthmarks are called capillary malformations, distinguishing them based on their appearance has several benefits:

1. Grouping Patients: By grouping patients with similar types of marks, doctors can learn about potential complications and predict outcomes. For example, certain types of marks may be more likely to cause overgrowth or other health issues.
2. Determining Appropriate Follow-Up: Recognizing differences in capillary malformations helps doctors decide on the necessary monitoring or follow-up care. Some types, for instance, may require regular eye exams or brain imaging.
3. Identifying Genetic Causes: Understanding differences in appearance allows doctors to investigate whether a specific genetic mutation is responsible for a type of capillary malformation. This knowledge can lead to targeted treatments tailored to individual patients, making therapies more effective and reducing unnecessary interventions.

Different Types of Capillary Malformations

1. Nevus Simplex (Salmon Patch or Stork Bite): Light pink marks commonly found on the face or neck of newborns, which usually fade as the child grows.
2. Port-Wine Stains: Dark red or purple marks that may darken over time and are sometimes associated with conditions like Sturge-Weber syndrome, which can affect the brain and eyes. These are typically linked to mutations in GNAQ or GNA11. Research shows that children with a GNA11 mutation and Sturge-Weber syndrome are less likely to experience epilepsy or cognitive impairments than those with a GNAQ mutation.
3. Reticulated Capillary Malformation: These marks may be associated with abnormal tissue growth, such as bones or other structures. This type is seen in macrocephaly-capillary malformation syndrome and in children with only the stain and limited overgrowth, such as in DCMO (Diffuse Capillary Malformation with Overgrowth). These are often linked to PIK3CA mutations, although many other genes can also be involved.
4. Geographic Capillary Malformations: Darker, well-defined marks often seen in syndromes such as Klippel-Trenaunay Syndrome or Cloves Syndrome.
5. Cutis Marmorata Telangiectatica Congenita (CMTC): A birthmark with characteristic tram-like, depressed purple lines. It is usually an isolated phenomenon not associated with specific genes. In the past, this term was sometimes used to describe what we now call “reticulated capillary malformations.”

Available Treatments

Treatment options vary depending on the type and severity of the capillary malformation. Common approaches include laser therapy to lighten port-wine stains and medications to manage associated health issues. Early diagnosis and personalized care are essential to improving outcomes and quality of life.

In Summary: There is not a single type of capillary malformation, but many.