Benign hereditary telangiectasia (BHT) occurs when small thread veins have dilated and are visible on the skin and lips. On dark skin, these veins may appear purple. On light skin, they may look red.
BHT is a type of primary telangiectatic condition, which means it is not a symptom of another illness. Instead, a person has inherited a genetic trait that causes the veins in the dermis (the middle layer of the skin) to dilate and become visible.
Hereditary hemorrhagic telangiectasia (HTT) has similar symptoms, but veins in the lungs, liver, and gut are also affected. This condition requires close monitoring and treatment. A doctor needs to rule out HTT or other causes of clusters of visible veins before diagnosing BHT.
This article explores BHT in more detail, including its causes, symptoms, diagnosis, and treatment.
A note about sex and gender
Sex and gender exist on spectrums. This article will use the terms “male,” “female,” or both to refer to sex assigned at birth. Click here to learn more.
BHT is an inherited skin condition that tends to present in childhood.
It usually only affects the skin and no other organs in the body. When the blood vessels expand or dilate, they leave oval-shaped marks or patches on the body called telangiectases.
The color of telangiectases can differ depending on skin tone, often appearing red on light skin and purple on dark skin.
Areas of the skin that experience sun exposure may have the most visible veins. As people get older, they may find the appearance of the veins fades with time.
Researchers do not understand what causes BHT.
However, they know it is a genetic condition that typically runs in families. BHT is autosomal dominant, which means that if one biological parent carries the trait, their child is 50% more likely to develop symptoms.
That said, some people can develop BHT even when they do not have a family history. For example, one
Although females tend to report telangiectases more than males, experts do not believe the condition affects more females than males. Some people report that their telangiectases became more visible during pregnancy.
Because telangiectases develop in areas of the skin that experience sun exposure, UV radiation may play a role in their development. However, researchers are unsure of the extent to which this is true.
Veins in people with BHT can be a
Typically, telangiectases appear on the:
- face
- neck
- upper torso
- upper back
- hands
They may also occasionally appear on the knees.
Telangiectases form in many ways. They may appear:
- spider-like
- net-shaped
- linear
- round with pale halos
When telangiectases are new, they may be deep red or purple, depending on the person’s skin tone. However, older telangiectases may fade with time.
To confirm a diagnosis of BHT, doctors tend to screen for HHT first. If a person does not have HHT, they may have BHT.
Diagnosing HHT
- Analysing family medical history: If a person experiences a lot of nosebleeds and HTT runs in the family, they could have HTT instead of BHT.
- Establishing when telangiectasias appeared: While telangiectasias tend to appear in childhood in BHT, a person with HTT may notice them at around 30 years old. The enlarged veins may also develop on the fingers and nose.
- Determining whether there are visceral arteriovenous malformations (AVMs) in major organs: AVMs are tangles of blood vessels that do not function effectively. They can disrupt blood flow and cause ruptures or bleeds in the brain. People with BHT do not have AVMs in the major organs, but those with HTT do.
- Genetic testing: People with a specific cluster of genes are typically more likely to develop HTT. Researchers have not yet identified a specific cluster of genes that increase the likelihood of a person developing BHT. However, BHT does run in families.
- Imaging: An MRI may be necessary when checking for the presence of AVMs.
BHT does not require treatment as it does not cause any harm to the rest of the body.
However, if a person wants to fade the exposed veins for cosmetic reasons, they may want to consider:
- Sclerotherapy: Sclerosant is a solution that causes blood vessels to disappear. A doctor injects it into the affected vein.
- Intense pulsed light: Pulses of high intensity light convert to heat energy, damaging the target blood vessels without affecting the skin or surrounding tissue.
- Vascular laser: This works similarly to intense pulsed light in that a laser heats up the blood vessels without damaging the surrounding tissue.
- Electrosurgery: This involves a high frequency electric current passing through the skin and generating heat, which destroys abnormal blood vessels.
BHT is a condition in which the veins in the dermis permanently dilate and expand, leaving telangiectases on the skin. Depending on skin tone, telangiectases may initially appear red or purple. However, some may fade over time.
The condition does not necessarily require treatment as it does not harm the body. However, if a person does not like how the veins look, there are several procedures that can reduce their appearance.