What are the other Names for this Condition? (Also known as/Synonyms)

• Naevus Anaemicus
• Pharmacologic Nevus

What is Nevus Anemicus? (Definition/Background Information)

• Nevus Anemicus is a skin disorder of congenital origin that presents hypopigmented macules (lesions that are of a lighter color than the surrounding skin). These macules are vascular malformations that do not turn red (erythematous) when subjected to hot or cold temperatures or trauma
• According to medical research, Nevus Anemicus develops from hypersensitivity reaction of the skin blood vessels to catecholamines that circulate in blood, resulting in permanent vasoconstriction. Nevus Anemicus is also associated with several genetic conditions such as neurofibromatosis and phakomatosis pigmentovascularis
• Individuals with Nevus Anemicus do not require any treatment since it is a benign skin disorder. There are also no complications associated with it. However, the overall prognosis may depend on its association with other genetic disorders

Who gets Nevus Anemicus? (Age and Sex Distribution)

• Nevus Anemicus is a rare disorder that is present at birth, but may be noticed only during early childhood
• Both males and females are affected, although a slight female preference is observed
• No racial and ethnicity predilection is observed for this skin disorder

What are the Risk Factors for Nevus Anemicus? (Predisposing Factors)

The risk factors of Nevus Anemicus are currently unknown. However, the condition is associated with several genetic disorders, which include:

• Neurofibromatosis type I (NF1)
• Phakomatosis pigmentovascularis (PPV)
• Tuberous sclerosis (TS)
• Telangiectatic nevus
• Becker nevus

It is important to note that having a risk factor does not mean that one will get the condition. A risk factor increases one's chances of getting a condition compared to an individual without the risk factors. Some risk factors are more important than others.

Also, not having a risk factor does not mean that an individual will not get the condition. It is always important to discuss the effect of risk factors with your healthcare provider.

What are the Causes of Nevus Anemicus? (Etiology)

• Nevus Anemicus is believed to arise due to vasoconstriction (narrowing of the blood vessels) in skin due to increased sensitivity to circulating catecholamines, such as adrenaline and noradrenaline
• The constriction of the blood vessels is typically permanent and leads to hypopigmentation of skin (patches of lighter skin) in the region
• The color variation from the surrounding normal skin is not from differences in melanin pigment. The color differences result from the local diminished contribution of skin tone by superficial blood flow

What are the Signs and Symptoms of Nevus Anemicus?

The signs and symptoms of Nevus Anemicus may include:

• Presence of a single, pale, or light-skinned patch (macule) that does not turn red on being subjected to minor trauma such as scratching or rubbing
• The surrounding normal skin can be stretched and compressed, forcing out the normal blood flow, to resemble similar hue of the Nevus Anemicus region
• In fair-skinned or lighter-skinned individuals, it may be difficult to spot Nevus Anemicus
• The nevus can appear anywhere on the body, but is usually observed on the trunk (chest or back)
• The shape of the skin lesion may be round, oval, linear, or irregular; some patches are also reticulated (net-shaped)
• There may be smaller satellite skin lesions around the main lesion
• The condition is typically asymptomatic, meaning it does not present any itching, pain, or burning sensation

Additional signs and symptoms of the associated genetic disorder, if any present, may be noted.

How is Nevus Anemicus Diagnosed?

The following tests and procedures may be used to diagnose Nevus Anemicus:

• Complete evaluation of the individual’s medical history and a thorough physical examination including of the skin
• Dermoscopy: It is a diagnostic tool where a dermatologist examines the skin using a special magnified lens
• Wood’s lamp examination: In this procedure, the healthcare provider examines the skin using ultraviolet light. It is performed to examine the change in skin pigmentation
• KOH tests to rule out a fungal infection
• A skin tissue biopsy is not helpful in diagnosing the condition

Tests and procedures to diagnose the associated disorder, if any present, is important.

A diagnosis of Nevus Anemicus is often difficult and challenging. Hence, a differential diagnosis to eliminate other skin conditions may be needed before arriving at a definitive diagnosis. These include:

• Achromic nevus
• Ash-leaf spots due to tuberous sclerosis
• Pityriasis alba
• Pityriasis versicolor
• Post-inflammatory hypopigmentation
• Progressive macular hypomelanosis
• Scarring
• Vitiligo

Many clinical conditions may have similar signs and symptoms. Your healthcare provider may perform additional tests to rule out other clinical conditions to arrive at a definitive diagnosis.

What are the possible Complications of Nevus Anemicus?

• There are usually no significant complications from Nevus Anemicus
• However, in some cases, the pale skin patches may result in cosmetic issues, which can lead to psychological stress
• The condition may be present for several years to decades

Complications of the associated disorder, if any present, may be noted.

How is Nevus Anemicus Treated?

• A majority of individuals do not require any treatment for Nevus Anemicus
• If these lesions are on the face or other exposed body areas, then masking them using suitable cosmetics may be suggested
• Nevertheless, managing the associated genetic condition is important

How can Nevus Anemicus be Prevented?

Current medical research has not established a method of preventing Nevus Anemicus.

What is the Prognosis of Nevus Anemicus? (Outcomes/Resolutions)

• The prognosis of Nevus Anemicus is generally good, since it is a benign and non-progressive condition that does not present any complications
• However, the overall prognosis may be dependent upon the severity of the associated genetic disorder (if any)

Additional and Relevant Useful Information for Nevus Anemicus:

• There is no evidence to prove that the tumor formation is influenced by one’s dietary choices
• Cleaning the skin too hard with strong chemicals or soaps may aggravate the skin condition. Care must be taken avoid strong soaps and chemicals that could potentially worsen the condition

The presence of dirt on the body is not a causative factor for the condition. However, it helps to be clean and hygienic, which may help the condition from getting worse