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

• Acquired Reactive Perforating Dermatosis
• Collagenoma Perforant Verruciforme
• RPC (Reactive Perforating Collagenosis)

What is Reactive Perforating Collagenosis? (Definition/Background Information)

• Reactive Perforating Collagenosis (RPC) is a very rare skin disorder that can manifest during early childhood or adulthood. In this abnormal condition, collagen fibers come out through (extrude from) the epidermis of skin
• There are two forms of Reactive Perforating Collagenosis - acquired (that is seen in adults) and inherited (that can be seen in children)
• The cause of the condition is generally unknown, but the contributing factors for Reactive Perforating Collagenosis may include chronic renal failure, poorly-controlled diabetes, hypothyroidism, and family history of the condition in case RPC is inherited
• Reactive Perforating Collagenosis is a chronic disorder that is characterized by the presence of single or multiple papules on the trunk, arms, and legs. The skin lesions grow over many weeks and are accompanied by itching
• The majority of the cases resolve on their own without any treatment. In case of severe Reactive Perforating Collagenosis, the treatment may include the use of topical creams and moisturizers, phototherapy, and antihistamines for itching
• The prognosis of Reactive Perforating Collagenosis is frequently excellent, with or without treatment. However, the symptoms can be longstanding; the skin lesions may appear, subside, and reappear over one’s lifetime

Who gets Reactive Perforating Collagenosis? (Age and Sex Distribution)

• Reactive Perforating Collagenosis is an extremely rare disorder; only less than 50 cases have been reported worldwide
• The acquired form of RPC occurs in adults and the inherited form of RPC is seen in young children
• It can affect both males and females and no gender preference is observed
• The condition can occur worldwide; individuals of all racial and ethnic background may be affected

What are the Risk Factors for Reactive Perforating Collagenosis? (Predisposing Factors)

The risk factors for Reactive Perforating Collagenosis may include the following:

• Individuals with chronic kidney failure and receiving dialysis
• Hypothyroidism and hyperparathyroidism
• Poorly-controlled diabetes
• A variety of liver diseases and disorders
• Lymph node malignancy such as lymphoma
• Presence of a family history of RPC for individuals with the inherited forms

It is important to note that having a risk factor does not mean that one will get the condition. A risk factor increases ones 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 Reactive Perforating Collagenosis? (Etiology)

• The exact cause of Reactive Perforating Collagenosis development is unknown, particularly for the acquired type
• The cause of inherited type of Reactive Perforating Collagenosis may be due to genetic factors, since generally there is a preceding family history for the condition
• In both the acquired and inherited type, the appearance of skin lesions is triggered by trauma, such as superficial scratching

What are the Signs and Symptoms of Reactive Perforating Collagenosis?

The signs and symptoms of Reactive Perforating Collagenosis include:

• The presence of 2-8 mm sized skin papules with keratotic centers
• The skin lesions grow over a period of weeks
• In this condition, there is collagen that comes out of the epidermis of the lesions
• In children with the inherited form, multiple lesions are observed
• Adults with the acquired form have a solitary lesion (and the condition is termed Collagenoma Perforant Verruciforme)
• Itching of skin
  • In the inherited form, the  hands, elbows, and knees are affected
  • In the acquired form, the trunk, arms, and legs are affected
• Scratching and cold weather makes the condition worse, especially in children with the inherited form
• The symptoms appear and disappear over a period of time

How is Reactive Perforating Collagenosis Diagnosed?

The following are the diagnostic methods that may be used for Reactive Perforating Collagenosis:

• A thorough physical examination and a complete medical history are very crucial
• Dermoscopy: Dermoscopy is a diagnostic tool where a dermatologist examines the skin using a special magnified lens
• Skin biopsy: A skin 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

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 Reactive Perforating Collagenosis?

The complications due to Reactive Perforating Collagenosis may include:

• RPC can be a longstanding and chronic condition; often the skin disorder waxes and wanes over the lifetime of the individual
• The condition can lead to self-image issues, emotional and psychological stress
• Bacterial and fungal infections: Reactive Perforating Collagenosis can cause continuous itching and scaling of the skin, which creates skin moistness, providing a suitable environment for bacteria and fungi to grow and thrive

How is Reactive Perforating Collagenosis Treated?

Many cases of Reactive Perforating Collagenosis are self-limiting and the condition gets better on its own without treatment. However, for severe cases, the treatment strategies that may be adopted include:

• Vitamin A therapy
• Antibiotics such as doxycycline
• Phototherapy
• Moisturizing creams and antihistamines to help with itching
• For mild skin conditions, self-care measures are recommended, such as washing with mild (antibacterial) soap and applying warm compress
• Reassurance may be provided in case of emotional stress
• Treatment and management of the underlying condition
• Follow-up care with regular screening and checkups are important

A few self-care tips and home remedies for Reactive Perforating Collagenosis may include:

• Completely avoid scratching the affected areas
• A comfortable, cool bath may help soothe the skin; but, avoid excessive washing and scrubbing of the skin
• Wear smooth cotton clothes
• Use only mild perfumes, soaps, and detergents
• Keeping the skin moist can help in reducing the signs and symptoms caused by RPC

How can Reactive Perforating Collagenosis be Prevented?

• Currently, there are no specific methods or guidelines to prevent Reactive Perforating Collagenosis
• However, proper treatment and control of diabetes and other associated disorders can be ensured to help lower one’s risk for RPC
• If there is a family history of the condition, then genetic counseling and genetic testing can help assess risks, before planning for a child

What is the Prognosis of Reactive Perforating Collagenosis? (Outcomes/Resolutions)

• The prognosis of Reactive Perforating Collagenosis is generally good, since most cases are self-limiting and heal on their own
• In case of severe skin condition, treatment measures are available to effectively treat the condition. However, some cases may be chronic and last lifelong
• The prognosis of RPC is also dependent upon the underlying health condition associated with it
• Regular follow up visits with the healthcare providers are important

Additional and Relevant Useful Information for Reactive Perforating Collagenosis:

• There is no evidence to prove that oily foods and chocolate-based products have an influence on Reactive Perforating Collagenosis
• 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. However, it helps to be clean and hygienic, which will help the condition from getting worse