What is Hydroa Vacciniforme?
Hydroa vacciniforme is an extremely rare skin condition that affects children. This condition leads to uncomfortable or painful blisters on skin areas exposed to sunlight. These blisters usually appear after sun exposure and tend to heal, leaving permanent acne-like scars. This condition was first described as a non-serious disorder in western countries due to its lack of internal symptoms and natural healing in teenagers or young adults.
However, a more serious and disfiguring version of this condition has been identified in children from Latin America and Asia, known as hydroa vacciniforme-like lymphoma. This more severe form is linked to an infection caused by the Epstein-Barr virus (EBV), a common type of virus that can cause various diseases. The World Health Organization has recognized this serious type of hydroa vacciniforme as a specific group of EBV-related disorders that cause an excessive production of harmful T-cells, a type of white blood cell, during childhood.
What Causes Hydroa Vacciniforme?
Hydroa vacciniforme is a skin condition that’s often triggered by exposure to ultraviolet radiation, commonly from sunlight. While sunlight is definitely involved in causing the specific skin issues related to the disease, we’re not exactly sure what else could be involved. Some have found a connection between this skin condition and a type of virus known as Epstein-Barr virus (EBV), indicating that sunlight might not be the only factor at play.
Interestingly, in some cases, skin issues related to hydroa vacciniforme can appear on areas of the body that aren’t usually exposed to the sun. These skin problems didn’t seem to get worse with sun exposure, suggesting that there might be other factors involved as well.
Some researchers also believe that EBV infection might be a result, rather than a cause, of hydroa vacciniforme. This is because the virus seems to be more frequently detected in people as the disease progresses. As a result, studies examining the relationship between EBV and hydroa vacciniforme sometimes misinterpret their findings, particularly in areas where the virus is widely spread, because other factors might be influencing the results.
Risk Factors and Frequency for Hydroa Vacciniforme
Hydroa vacciniforme is a disease that mostly occurs in children. It is most common in early childhood (between 1 to 7 years old) and around or after puberty (between 12 to 16 years old). The disease typically begins in the spring or summer months. While rare, it can still happen in infants and adults. Males and individuals with lighter skin tones are a bit more likely to get the disease, though this isn’t always the case as there are differing opinions on whether sex impacts the likelihood of getting the disease. People with darker skin tones are more likely to have a version of the disease that resembles lymphoma. It is extremely rare for the disease to affect multiple members of the same family, with only three such cases reported.
- Hydroa vacciniforme mainly affects children.
- The disease commonly starts during early childhood (1 to 7 years old) and around puberty (12 to 16 years old).
- It often starts in the spring or summer.
- Though rare, the disease can occur in infants and adults.
- Males and people with lighter skin tones are somewhat more likely to get the disease.
- People with darker skin are more likely to have a version of the disease that looks like lymphoma.
- Familial cases of the disease are extremely rare.
Signs and Symptoms of Hydroa Vacciniforme
Hydroa vacciniforme is a skin condition that typically starts as symmetrical, itchy, or burning red spots on sun-exposed areas like the face and backs of the hands. Usually, these spots appear within hours of exposure to the sun. Later, the spots can become tender bumps or raised areas surrounded by small fluid-filled blisters or blisters filled with blood. After a few days, the spots become indented in the center and develop secondary crusts. They heal over a few weeks, leaving pockmark-like scars. Rarely, the disease can also affect the eyes and cause deformities of the ear and nose, or contractions of the fingers.
However, in a condition called Hydroa Vacciniforme-Like Lymphoma, the symptoms present more severely. Patients tend to have a noticeable swelling of their face, multiple blisters, large crusted sores, and serious scarring on sun-exposed and non-sun-exposed areas. In addition, they often experience more full-body signs and symptoms such as high fevers, swollen lymph nodes, and an enlarged liver and spleen. They can also get Epstein-Barr virus related problems like increased sensitivity to mosquito bites, a condition that causes the body’s immune cells to over activate and damage tissues, and a long-term active Epstein-Barr virus infection.
Testing for Hydroa Vacciniforme
To diagnose classic hydroa vacciniforme, a type of skin condition, doctors look at the symptoms that the patient presents and use a type of test known as a histopathologic examination, which studies cells and tissues under the microscope.
In order to distinguish between typical hydroa vacciniforme – which is a benign (non-cancerous) skin condition, and the more serious hydroa vacciniforme-like lymphoma – which is a type of skin cancer, the following tests can be very helpful:
* Blood and liver checks – these looks at the health of your blood cells and liver.
* Assessing the percentage of a type of white blood cell known as NK lymphocytes – these cells help control your immune response.
* T-cell receptor gene rearrangement – this is a particular change (or rearrangement) in certain genes that code for T-cells, which are another type of immune cell.
* Checking the levels of anti-EBV antibodies – antibodies are proteins produced by the body to defend against harmful substances. The Epstein-Barr virus (EBV) is known to be associated with certain skin conditions, so high levels of these antibodies could suggest an ongoing response to this virus.
* Checking the levels of EBV DNA present in the blood – this can give an indication of how much EBV is present in the body.
People with hydroa vacciniforme-like lymphoma often have high levels of liver enzymes (a sign that the liver might not be working properly), low levels of white blood cells and platelets (cells that help blood clot), increased numbers of NK lymphocytes, changes in the arrangement of T-cell receptor genes, and high levels of EBV DNA in the blood.
Treatment Options for Hydroa Vacciniforme
Currently, there’s no one-size-fits-all treatment for this condition. The most common approach is to avoid the sun as much as possible. This means using sunscreens that protect against both UVA and UVB rays, wearing clothes that block the sun, tinting windows, and staying inside when the sun is at its peak. Various medications, including antimalarials, azathioprine, cyclosporine, thalidomide, beta-carotene, and oral fish oils, have shown mixed success in treating the condition.
An interesting approach, called “hardening,” involves exposure to a specific type of UVB light, known as narrowband UVB light. This light is given in low doses during the spring months, and it might help to decrease the severity of the disease.
What else can Hydroa Vacciniforme be?
When doctors are considering a diagnosis of a skin condition called hydroa vacciniforme, there are several other conditions which could cause similar symptoms. These include:
- Erythropoietic protoporphyria – a rare metabolic disorder
- Vesicular polymorphic light eruption – skin reaction to sunlight
- Actinic prurigo – a skin rash caused by sun exposure
- Bullous lupus erythematosus – a form of lupus that affects the skin
- Hartnup disease – a inherited disorder affecting skin and nervous system
What to expect with Hydroa Vacciniforme
People who have hydroa vacciniforme, a rare skin condition, often experience significant emotional and social challenges. The need to manage their daily activities and make lifestyle adjustments to minimize the effects of their disease can significantly affect their quality of life. What’s more, the permanent scarring that results from this disease can greatly impact their lives.
Hydroa vacciniforme, which can evolve into a type of skin cancer called hydroa vacciniforme-like lymphoma, tends to be quite aggressive and life-threatening, especially when the disease spreads to areas beyond the skin. According to a study, 8 out of 12 patients passed away from complications related to this disease, with an average of 5.3 months after they were first diagnosed.
Possible Complications When Diagnosed with Hydroa Vacciniforme
The most worrisome complication is the development of a type of skin cancer known as hydroa vacciniforme-like lymphoma. This has been observed in a few studies. This type of cancer can be aggressive and even deadly. Therefore, it’s recommended that patients be monitored for at least 10 years after diagnosis, even if the disease initially goes into remission.
Preventing Hydroa Vacciniforme
It’s very important for patients to understand that they need to avoid the sun, particularly during the middle of the day, and to use proper sun protection. This sun protection should protect against a wide range of sunlight (both UVA and UVB types). Patients also need to know that normal window glass doesn’t block out UVA sunlight, so staying indoors doesn’t mean they can forget about sun safety. Even while inside, steps to avoid sun exposure are still needed.
