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

• Juvenile Papular Dermatitis
• Recurrent Pityriasis of the Elbows and Knees
• Sutton’s Summer Prurigo

What is Frictional Lichenoid Dermatitis? (Definition/Background Information)

• Frictional Lichenoid Dermatitis (FLD) is a condition that arises in skin areas subjected to constant or short-term friction from a variety of activities, such as sports, playing an instrument, or even using a computer mouse. The condition is more common in children, especially those having a genetic susceptibility for allergic conditions (termed atopy)
• Thus, Frictional Lichenoid Dermatitis occurs more frequently in individuals who have history of eczema or atopic dermatitis. In some cases, the friction may not be significant, but it may still trigger an immune response resulting in signs and symptoms of the condition
• In Frictional Lichenoid Dermatitis, a rubbing and scratching of skin surface results in lichenification, which is marked by skin thickening, scale formation, and dryness, at the point of contact. Most of these lesions have been observed on the knees or elbows
• The condition is mostly self-resolving. If needed, the healthcare provider may recommend treatment using topical creams and ointments, including the use of corticosteroids. The prognosis of Frictional Lichenoid Dermatitis is usually excellent

Who gets Frictional Lichenoid Dermatitis? (Age and Sex Distribution)

• Frictional Lichenoid Dermatitis is generally observed in children between 4 and 12 years (age of onset), although individuals of a wide age range may be affected
• Both males and females are affected, although 75% of the cases are reported in boys than girls
• Worldwide, there is no racial or ethnic preference observed

What are the Risk Factors for Frictional Lichenoid Dermatitis? (Predisposing Factors)

The risk factors for Frictional Lichenoid Dermatitis (FLD) include:

• Atopic eczema
• Family history of atopy (atopic dermatitis or eczema)
• Any activity associated with friction such as participation in sports, use of certain devices, playing musical instruments, etc.
• Minor trauma
• Frequent skin contact with abrasive or rough materials such as sand, metal, or even coarse rugs. Playing in sandboxes or on carpets are sometimes implicated
• Ultraviolet radiation from sun exposure
• FLD is more commonly observed during springtime and summer

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 Frictional Lichenoid Dermatitis? (Etiology)

Frictional Lichenoid Dermatitis (FLD) develops as a physiological response of the body to friction, in order to prevent further skin injury and manage the body’s need for increased turnover rate of skin cells (epidermal cells).

• The friction or minor trauma triggers an immune response that results in the characteristic signs and symptoms of the condition
• FLD occurs more frequently in individuals who have eczema or atopic dermatitis

What are the Signs and Symptoms of Frictional Lichenoid Dermatitis?

The signs and symptoms of Frictional Lichenoid Dermatitis (FLD) depend on the underlying activity causing the condition. it may vary from one individual to another and may be mild or severe. The morphological presentations are described as mild, moderate, or severe.

The signs and symptoms of FLD may include:

• Presence of numerous lichenoid (slightly elevated, flat-topped) papules at the contact surface of skin. These may appear as scratch marks
• The size of each papules are usually between 1-3 mm
• In many individuals, the papules combine to form large patches known as plaques
• These dry skin patches may be reddish, pale to dark, or flesh-colored
• The condition may be associated with scale formation
• No pain, discomfort, or irritation is noted. In some, mild itching sensation may be seen
• Most of the lesions are observed on the knees, elbows, and dorsal (top) surface of the hands
• To a lesser extent, FLD may be noted on the buttocks, trunk, neck, or face

No other systemic signs and symptoms are noted.

How is Frictional Lichenoid Dermatitis Diagnosed?

A diagnosis of Frictional Lichenoid Dermatitis may involve the following exams and procedures:

• Physical examination of the individual and medical history evaluation, including evaluating one’s daily activities, sports participation, and a family history of allergic conditions
• Dermoscopy: Dermoscopy 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
• Skin biopsy: A skin tissue biopsy is performed and sent to a laboratory for a pathological examination. The pathologist examines the biopsy under a microscope. After putting together clinical findings, special studies on tissues (if needed) and with microscope findings, the pathologist arrives at a definitive diagnosis. A skin biopsy is not usually required

A differential diagnosis is important to exclude skin disorders that present similar signs and symptoms. These may include:

• Atopic dermatitis
• Dermatomyositis
• Flat warts
• Gianotti-Crosti syndrome
• Keratosis pilaris
• Lichen simplex chronicus
• Molluscum contagiosum
• Psoriasis

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 Frictional Lichenoid Dermatitis?

The possible complications due to Frictional Lichenoid Dermatitis include:

• Emotional stress due to cosmetic issues
• On resolution of the condition, light or dark pigmentation at the affected area may be noted
• Recurrence of the condition
• Treatment complications

How is Frictional Lichenoid Dermatitis Treated?

The treatment measures available for Frictional Lichenoid Dermatitis include:

• Administration of topical applications (low or moderate potency corticosteroids)
• Use of topical keratolytic agents
• Moisturizing creams for dry skin

In many individuals, no treatment is needed as the condition is self-limited.

How can Frictional Lichenoid Dermatitis be Prevented?

In many cases, it may not be possible to prevent Frictional Lichenoid Dermatitis.

• Individuals with atopic dermatitis may consider adequate treatment of the condition
• Activities that cause frictional trauma may be potentially avoided, where possible, or modified to minimize the risk

What is the Prognosis of Frictional Lichenoid Dermatitis? (Outcomes/Resolutions)

• The prognosis of Frictional Lichenoid Dermatitis (FLD) is excellent with adequate treatment as it is a benign condition
• In most cases, FLD is known to resolve spontaneously within a few weeks to months, and the outcomes are generally excellent

Additional and Relevant Useful Information for Frictional Lichenoid Dermatitis:

The following DoveMed website link is a useful resource for additional information:

https://www.dovemed.com/healthy-living/skin-disorders/