What is Acrokeratoelastoidosis (Genetic Skin Lesions)?

Acrokeratoelastoidosis (AKE), also known as inverse papular acrokeratosis, is a rare skin condition that was first identified by Oswaldo Costa, a Brazilian dermatologist, in 1952. This condition usually appears as flesh-colored bumps on the sides of one’s palms, soles, and the back of their hands. It is a type of skin concern known as marginal keratoderma that typically targets the side areas of the palms and soles.

While this condition is usually hereditary, there have been reported cases of it occurring spontaneously. Study of the skin under a microscope shows features such as thickened and smooth collagen, excess skin growth, and a decrease in and breaking down of the elastic fibers in the skin.

It’s a rare skin condition that we don’t know much about and typically starts in childhood, although symptoms may not appear until the adolescent years. According to the limited research on this condition, it does not seem to affect a specific gender or race more than another. One reason some patients may not seek medical advice until years after the symptoms start is that the skin changes do not cause any discomfort.

Diagnosing this condition involves distinguishing it from other similar skin conditions and unique disorders such as acrokeratosis verruciformis of Hopf. This classification is usually achieved by evaluating the skin under a microscope. There have been no reported negative health impacts associated with this condition, and other than the appearance of the skin, its overall long-term outlook is good.

What Causes Acrokeratoelastoidosis (Genetic Skin Lesions)?

Acrokeratoelastoidosis is primarily believed to be a genetic skin condition. It usually follows the autosomal dominant pattern of inheritance, which is a way that a trait or disorder can be passed down in families. However, some isolated cases indicate there might also be an autosomal recessive inheritance – a lesser observed pattern.

Palmoplantar keratoderma (PPK) is a grouping of skin disorders and acrokeratoelastoidosis is regarded as one type of this group, specifically known as Type 3 PPK. Understanding how these skin conditions link to the genetic code, scientists have figured out that there are three different types with each having connections with specific locations on our genes. The one specifically linked to acrokeratoelastoidosis shows a connection to a spot on chromosome number 2.

Interestingly, another gene named AAGAB associated with a type of PPK, doesn’t seem to have a role in acrokeratoelastoidosis. However, in the case of the associated PPK type, scientists find that this gene’s reduced activity increases skin cell growth. At this stage, it’s not out of the question to think that a similar gene-behavior dynamic could play a role in acrokeratoelastoidosis, and this certainly warrants further research.

On the other hand, some factors responsible for causing acrokeratoelastoidosis are less clear. While a history of consistent physical injuries and excessive sunlight has been noted in a few instances, there’s no concrete proof that these forces directly cause the condition.

The condition usually presents as skin lesions that occur mainly on our extremities – the hands and feet. However, some researchers have suggested that acrokeratoelastoidosis could be linked to a defect in the body’s elastic tissue, affecting parts of the skin that might otherwise seem normal. It is possible that areas of the body frequently subjected to unnoticed injury, such as the hands and feet, might end up showing signs of the disorder more prominently.

Intriguingly, similar skin lesions have been reported in patients with scleroderma, a disease of abnormal tissue growth. Other curious observations include unusual sweating and a water-induced skin disorder, though the connections with acrokeratoelastoidosis are still unclear.

Risk Factors and Frequency for Acrokeratoelastoidosis (Genetic Skin Lesions)

The disease does not come about from birth, instead, it typically starts in childhood or adolescence. There doesn’t seem to be a bias towards any particular sex or ethnicity based on the relatively small number of cases reported. Due to the rare occurrence of this disease, we’re not sure exactly how often it happens.

Most cases of this disorder, known as AKEs, are seen starting before the second and third decades of life.
The youngest reported age of a patient with AKE was 3 years old.
Even though the disease typically affects both sides, there have been a few cases where only one side was involved.
These one-sided cases might occur due to a phenomenon called genetic mosaicism.
While some researchers have noted a rise in the number of skin bumps (papules) over time, there isn’t a general agreement on this observation.

Signs and Symptoms of Acrokeratoelastoidosis (Genetic Skin Lesions)

Acrokeratoelastoidosis is a skin condition that often shows up in children and adolescents, usually before their 20s. However, there are also instances where this condition starts appearing in adults. It is characterized by small, round or oval bumps that are colorless, translucent or yellow. They are generally found on the sides of the hands and/or feet. These bumps feel rough and may have a dipped appearance.

Another term for acrokeratoelastoidosis is ‘papular acrokeratosis’, which refers to these characteristic bumps and their location. Sometimes, these bumps can also be found on the top side of the hands/feet, feet’s inner back border, and the front part of the leg. They usually are arranged symmetrically on both sides of the body, but there are cases of them only appearing on one side. These bumps can also merge together to form a larger patch.

Most of the time, apart from the change in appearance, these bumps do not cause any issues. However, some people may experience mild itching, excessive sweating, and thickened skin that usually occurs when in contact with water. In many cases, a family history of this condition is common as it is generally passed down from parent to child. Factors like physical harm to the hands and feet, and excessive sun exposure may play a role in its development. Furthermore, things like frequent hand washing, clothes and ill-fitted footwear that rub the skin may lead to an increase in the number and size of these bumps.

In most cases, the condition stabilizes after several weeks to months from when it first shows up. However, some have noted that the condition rapidly progressed during pregnancy.

Testing for Acrokeratoelastoidosis (Genetic Skin Lesions)

Looking at the human skin using a polarized videodermoscopy allows doctors to examine the affected areas of thumbs and index fingers. This test usually reveals small clusters of pale or yellowish-colored bumps with minor indentations in a few of them, mixed with pale yellow-colored featureless regions.

Despite advances in imaging, a biopsy or tissue test, known as histopathology, is still the go-to method for diagnosing acrokeratoelastoidosis. Among various skin changes, the key diagnostic sign is a decrease in the count of elastic fibers in the skin that appear thick and broken down, a condition known as ‘elastorrhexis’. This key sign can be spotted even in a routine tissue test but is more clearly seen when special dyes are used that specifically color elastic fibers.

An ultrasound scan which uses Doppler is another tool that has recently been found useful. It offers a non-invasive way to support the diagnosis and confirm that the condition is not harmful. This technique also helps dismiss other shades of the disease with similar symptoms such as piezogenic pedal papules and granulomas. In those with acrokeratoelastoidosis, a Doppler ultrasound shows several distinct solid areas that throw back lesser sound waves (hypoechoic) and have less blood flow (hypovascular), along with thickening of the outermost layers of the skin.

Treatment Options for Acrokeratoelastoidosis (Genetic Skin Lesions)

Acrokeratoelastoidosis is a harmless condition that doesn’t cause symptoms, but some patients may seek treatment because they are concerned about their appearance. There are several ways to treat acrokeratoelastoidosis, but they generally only produce modest improvements in skin appearance. These treatments include:

1. Topical treatments – These are applied directly to the skin and include emollients and keratolytic agents like salicylic acid, urea, sulfur, coal tar and tretinoin. These methods can soften the skin and help it shed easily. Topical corticosteroids, another form of treatment, can also help reduce inflammation.

2. Oral treatments – This type of treatment is taken by mouth and includes corticosteroids, antibiotics, dapsone, methotrexate, isotretinoin and acitretin. These medications can help control the body’s immune response and reduce skin abnormalities.

3. Physical/surgical treatments – Options include freezing the affected areas with liquid nitrogen (cryotherapy) or using a special type of laser (erbium: yttrium-aluminum-garnet, or Er: YAG) for surgery.

Among these, oral retinoid treatment – particularly using acitretin – is considered the most effective, but the condition tends to come back after treatment is stopped.

When patients with acrokeratoelastoidosis consider receiving treatment to improve their appearance, it’s crucial they understand three things beforehand:

1. Treatment generally only produces minor improvements.

2. For topical treatments, it may be necessary to use the treatment indefinitely to keep up any improvement.

3. With oral or systemic (affecting the whole body) therapy, there’s a high chance the condition will return once the medication is stopped. Also, these treatments can have side effects.

When trying to diagnose certain skin conditions that involve the edges and extremities of the body (such as hands and feet), doctors need to consider ‘marginal and acral keratodermas’, as these disorders cause similar skin changes.

‘Marginal keratodermas’ are defined by skin changes on the edges or transition areas between the palms and soles. If these changes also appear on the back of the hands and feet, it can be termed ‘inverse’.

Focal acral hyperkeratosis: This condition can be identified by its specific changes in the skin’s outer layer under a microscope, characterized by the lack of damage to the elastic tissue of the skin.
Keratoelastoidosis marginal (also known as Ramos and Silva marginal keratoderma): This is related to extensive sun exposure and tends to show notable sun damage.
Other acral keratoderma types: These include inherited skin conditions like hereditary papulotranslucent acrokeratoderma, acrokeratoderma hereditarium punctatum, and punctate palmoplantar keratoderma.
Other possible related conditions: These include other skin disorders such as acrokeratosis verruciformis of Hopf, degenerative collagenous plaques (of the hands), digital papular calcinosis, flat warts, primary skin amyloidosis, and mosaic acral keratosis.

In summary, doctors consult these potential conditions when diagnosing skin disorders to ensure an accurate diagnosis.

What to expect with Acrokeratoelastoidosis (Genetic Skin Lesions)

PPK, or palmoplantar keratoderma, represents a range of skin conditions. Some types of PPK, including certain kinds of PPKP (a subtype of PPK), can serve as warning signs for serious health problems. But there’s one subtype known as AKE, which is harmless and not associated with any other medical conditions.
Although its treatment might not always work well and the skin lesions can last a long time, the overall outlook for this condition is generally excellent.

Possible Complications When Diagnosed with Acrokeratoelastoidosis (Genetic Skin Lesions)

There are no known or reported negative side effects of acrokeratoelastoidosis.

Preventing Acrokeratoelastoidosis (Genetic Skin Lesions)

This particular health issue may present some challenges like the appearance change due to bumpy skin and the difficulty in treating the persistent lumps caused by Acrokeratoelastoidosis of Costa. It can be stressful for both patients and their families. But this condition generally has a good outlook and doesn’t worsen over time.

It’s really important to understand that teaching the patient and their family about the harmless nature of this condition is often more critical than trying to suggest treatments that might improve the appearance of the bumps. This simple understanding can help to alleviate any potential worries and concerns.

Even though this condition is easy to diagnose by just looking at the skin, it might be helpful to have a skin biopsy done to further confirm that this condition is harmless. Many people often associate ‘biopsy’ with serious diseases like cancer. But in this case, the biopsy results for Acrokeratoelastoidosis simply confirm its harmless nature and could provide additional peace of mind.

Effective communication and education from the doctor will go a long way in reassuring the patient, helping to demystify the condition and make dealing with it easier on the patient and their family.