Familial venous malformations are lesions caused by improperly formed veins that may be visible on the skin, in the digestive tract, or in other organs. Due to a genetic mutation or change, veins (which carry blood back to the heart) do not have enough smooth muscle cells. This causes areas of the veins to swell or enlarge. Sometimes, the valves in the veins fail. Blood clots may also form, but they do not tend to travel. Some cases are caused by a mutation or change in the TEK gene but changes in other genes are also believed to be involved. Reported cases have autosomal dominant inheritance, meaning you only need to inherit one changed gene to have the condition (genes come in pairs, one from each parent).
Symptoms may vary based on the location of the lesion. The venous malformations are present at birth but may not be visible because of their location. If the improperly formed vein is close to the skin, the skin may appear blue. Lesions in different veins may affect vision or cause breathing problems. If there is a lesion in the vein of a person’s limbs, the affected limb may be larger than the unaffected limb. The lesion may get bigger or more noticeable for many reasons, including injury, puberty, trauma, infection, and pregnancy.
In order to diagnose familial venous malformations, your doctor will ask questions about your family history. Imaging tests, such as ultrasounds, MRIs, and CT scans are used to confirm the diagnosis. Treatment options may include using compression garments, blood-thinning medication, injections, or surgery. However, many venous malformations do not need treatment. Research is ongoing, so talk to your doctor about what current treatment options are right for you. A genetic counselor can help explain how the condition runs in families and what testing options are available. Support groups can be a good source of information and means of connecting to others for support.