Pityriasis is a common skin condition which is characterized by reddish pink and scaly rashes. This condition is more common in children than in young adults. It occurs commonly in people aged between 10 to 35 years. There is a high incidence of pityriasis in the months of spring and autumn.
The pityriasis rash appears to be dramatic, but the illness is very mild. This condition is harmless and not contagious. The rash is limited to the trunk, arms and legs. This condition is not caused by food, stress or hormonal changes.
TYPES OF PITYRIASIS
Pityriasis alba: It usually affects the children and teenagers. This condition usually affects people having dry skin following exposure to heavy sunlight. The skin becomes hypopigmented and round to oval, scaly patches develop on the face, upper arms, neck or shoulders.
Pityriasis rosea: It is more common in women of age between 15 and 40 years. It is a mild inflammatory condition of unknown origin. The skin first develops herald patch (round, scaly, pink patch), it commonly affects skin of the trunk and areas that are exposed to sun. In some people, it can also affect the neck, thighs, groins, or axillae.
Pityriasis rubra pilaris: This is a chronic skin disease. The skin eruption commonly occurs in the sides of neck and trunk and extensor; surfaces of the extremities. It is characterized with small papules, widespread yellowish pink patches in the palms of hands and soles of legs. The important diagnostic feature of this condition is presence of reddish brown papules which are about pinhead size, and are topped by a central horny plug.
Pityriasis Versicolor (tinea versicolor): It is most common fungal disease which affect the people who are frequently exposed to sunlight and living in areas with high humidity and high temperatures. It affects the young adults and affects the skin of upper trunk and extending on to the upper arms. The patches appear as yellowish-brown macules in pale skin or hypopigmented macules in dark skin.
SIGNS AND SYMPTOMS
The following are the signs and symptoms of pityriasis which occur before the rashes develop
- Feeling of sickness (nausea)
- High body temperature (fever)
- Mild headache
- Loss of appetite
- Sore throat
Pityriasis rash begins as a single, round or oval pink patch that is scaly (herald patch). A week later, multiple patches may appear on abdomen, chest, back, arms, and legs and turn in to salmon colored oval patches. In some people, a couple of herald patches may appear together. Patches that develop on the back are usually vertical and angled(fir tree appearance). These rashes may be mildly itchy.
In young children, women, and people who have dark skin, the rash may appear as rounded bumps (papular rash).Blisters (vesicular rash) are more likely in infants and young children.
Limited information is available regarding the cause of pityriasis. Certain strains of virus such as herpes virus and certain medications may cause a rash similar to pityriasis. Rash occurring in other skin conditions, such as ringworm of the skin, tinea versicolor, eczema, syphilis and psoriasis may resemble rash of pityriasis.
The following are the risk factors associated with pityriasis.
- Age: 10 to 35 years
- Gender: Female gender
Complications of pityriasis are rare and may include following:
- Skin may get scarred with brown spots
- Severe itching
The doctor may perform a thorough and careful examination of the skin rash.
Skin biopsy: This is rarely done. The skin sample is taken from the infected area and sent to laboratory for microscopic examination.
Potassium hydrochloride test: The doctor may do potassium hydrochloride test to rule out fungal infection. This test is specific in detecting fungal infections from other skin diseases.
Blood tests:They helpto rule out other conditions that may cause rashes similar to that of pityriasis.
Pityriasis usually resolves without any treatment within 6 to 8 weeks. If the rashes persist for a longer time consult a doctor. Your doctor may plan the treatment based on the following factors:
- Your tolerance for specific medicines, procedures, or therapies
- Your age, overall health, and medical history
- Your opinion or preference
- Your severity of the rash
The following treatment strategies should be useful to manage pityriasis in severe cases:
- Corticosteroid drugs to relieve itching and relieve rash
- Ultraviolet radiation to reduce the radiation
- Cool baths with or without oatmeal to soothe the itching
- Calamine lotions and steroid creams to reduce itching
- Cool compresses to soothe the affected skin
- Oral antihistamines to relieve itching
Pityriasis can resolve by itself without requiring any treatment. It is not contagious and rarely reoccurs. The affected skin remains clear after the lesions disappear.