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

• Chronic Superficial Large Plaque Dermatosis
• LPP (Large-Plaque Parapsoriasis)
• Parapsoriasis en Plaques

What is Large-Plaque Parapsoriasis? (Definition/Background Information)

• Plaque parapsoriasis is a skin condition that resembles psoriasis. It is caused by an abnormal inflammation of the skin. The skin lesions appear as scaly patches and plaques
• It is a rare condition that occurs worldwide. There are two types of plaque parapsoriasis:
  • Small-Plaque Parapsoriasis
  • Large-Plaque Parapsoriasis
• Large-Plaque Parapsoriasis (LPP) is observed as pinkish to red patches on the skin measuring over 5 cm in size. The lesions can appear on the chest or back, and itching is not commonly observed
• Large-Plaque Parapsoriasis can evolve into the mycoses fungoides form of cutaneous T-cell lymphoma (CTCL). Some of the patches may show the CTCL pathology changes with others unchanged
• In general, individuals in the 30-60 years’ age group are affected the most. There is a slight male predilection for Large-Plaque Parapsoriasis
• The treatment for the condition may include the use of topical corticosteroid creams and moisturizers, photochemotherapy (PUVA), and the treatments for  mycoses fungoides
• The prognosis of Large-Plaque Parapsoriasis is dependent upon whether it evolves to the mycoses fungoides type of cutaneous T-cell lymphoma (CTCL)

Who gets Large-Plaque Parapsoriasis? (Age and Sex Distribution)

• Large-Plaque Parapsoriasis is a rare skin condition that is typically seen in middle-aged to older adults in the age group of 30-60 years
• It can affect both males and females, although males are affected slightly more than females
• In general, LPP occurs worldwide and individuals of all racial and ethnic background may be affected

What are the Risk Factors for Large-Plaque Parapsoriasis? (Predisposing Factors)

• The risk factors for Large-Plaque Parapsoriasis are currently unknown or unidentified
• An association with the human herpes virus HHV8 in Large-Plaque Parapsoriasis has been reported. Subsequent studies have not confirmed those results; the association is not settled at this time

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 Large-Plaque Parapsoriasis? (Etiology)

The exact cause of development of Large-Plaque Parapsoriasis (LPP) is presently unknown.

• The condition may be caused by an abnormal inflammatory reaction that takes place due to as yet unascertained reasons
• Almost all cases of Large-Plaque Parapsoriasis are involved with mycoses fungoides. Some experts believe that LPP is an early stage of cutaneous T-cell lymphoma
• The possible role of HHV8 in Large-Plaque Parapsoriasis is uncertain
• LPP is non-contagious and is not transmitted from one individual to another; one cannot contract the condition through close physical interaction with the affected individuals

What are the Signs and Symptoms of Large-Plaque Parapsoriasis?

Large-Plaque Parapsoriasis develops slowly over a long period of time, usually months and years. The signs and symptoms (skin lesions) can last for years and sometimes lifelong.

The signs and symptoms of LPP may include:

• The skin lesions are slow-growing and appear as pink to red patches
• Despite the name containing “plaque”, the lesions are not thick and firm as plaques are defined. The individual large lesions are very slightly elevated  
• The affected skin looks thin and wrinkled; white flaky scales can be present on it
• The patches can be seen on the chest, back (trunk), hips or buttocks
• Itching sensation is usually absent
• The size of the lesion is usually greater than 5 cm
• Signs and symptoms of mycoses fungoides

The lesions usually disappear after exposure to sun, such as in summer months and reappears during winters.

How is Large-Plaque Parapsoriasis Diagnosed?

The following are the diagnostic methods and tests that may be used for Large-Plaque Parapsoriasis:

• 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
• 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
• Molecular studies for T-cell gene arrangement is helpful in diagnosing mycoses fungoides
• Skin biopsy: A skin biopsy is performed and sent to a laboratory for a pathological examination, who 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 performed to rule out other similar conditions

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 Large-Plaque Parapsoriasis?

The complications of Large-Plaque Parapsoriasis may include:

• In some individuals, the condition may present cosmetic issues
• The lesions are usually longstanding and can last for years resulting in self-image issues, emotional stress, and psychological trauma in some individuals
• LPP can transform into mycoses fungoides, a type of cutaneous T-cell lymphoma (CTCL). Published rates of this vary from 10-35% over 6 to 10 years

How is Large-Plaque Parapsoriasis Treated?

The treatment strategies that may be adopted in the management of Large-Plaque Parapsoriasis (LPP) include:

• Use of topical corticosteroid creams and lotions
• Topical calcineurin inhibitors or coal tar products
• Phototherapy
• Photochemotherapy (PUVA) when the response to medications and unaugmented phototherapy is poor
• Treatment with bexarotene, a topical retinoid, or imiquimod, an immune system modifier
• Providing reassurance and helping with feelings of stress and anxiety
• Treatments for mycosis fungoides in the event of transformation to that disease

Follow-up care with regular screening and checkups are important, since the condition can last for many months and years, and to assess the progress and development of mycoses fungoides.

A few self-care tips and home remedies for LPP 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
• Drinking lots of water or fluids

How can Large-Plaque Parapsoriasis be Prevented?

• Currently, there are no specific methods or guidelines to prevent Large-Plaque Parapsoriasis
• A careful and periodic monitoring or follow-up of the condition is highly recommended

What is the Prognosis of Large-Plaque Parapsoriasis? (Outcomes/Resolutions)

• Large-Plaque Parapsoriasis (LPP) is a longstanding condition, which can last for many years; sometime, for the entire lifetime after onset. The prognosis of LPP is related to the progression and treatment if mycoses fungoides eventuates
• Nevertheless, individuals with milder signs and symptoms have a better prognosis than those with severe signs and symptoms
• Regular follow up visits with the healthcare providers are important

Additional and Relevant Useful Information for Large-Plaque Parapsoriasis:

• Some researchers believe that Small-Plaque Parapsoriasis and Large-Plaque Parapsoriasis are related to each other, while others say that these are two different disease processes
• There is no definitive proof that certain types of diet play a role in the development of this skin condition
• 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 does not cause the condition. However, it helps to be clean and hygienic, which will help the condition from getting worse