What is Pityriasis Alba?
Pityriasis Alba is a benign and common skin disorder commonly affecting children and young adults. The disease is characterized by the development of reddish and flaky patches in round or oval shape. It is a self-limiting disease that does not necessitate treatment although it often leaves a pale mark once the redness has subsided.
Pityriasis Alba is not a contagious skin disorder and is non-cancerous. It strikes children and young adults mostly younger than 16 years of age. People from all age levels, however, can also get affected by this skin condition. It can affect many people regardless of racial group although a slight prevalence is found among people with light skin tone. Pityriasis Alba can also affect both men and women, but with a slight prevalence among the male gender. The disease is also found to be prevalent in children ages 6 to 16 years old and living in tropical countries.
Pityriasis Alba is a self-limiting disease with a good prognosis and does not leave a long-term effect. It is, however, a skin condition that can have a cosmetic concern due to the unappealing appearance of the skin patches. The cosmetic concern may not be an issue to the patient, but more of an issue for the parents.
Pityriasis Alba is a skin disorder belonging to the group of Pityriasis. Pityriasis is the term for a group of disease commonly manifested by a scaly lesion. Pityriasis Alba on the other hand is generally a harmless skin disorder that usually becomes more apparent during the hot summer months.
Pityriasis Alba usually occurs in the face particularly on the cheeks. It may also occur in the neck, upper arms and the upper middle portion of the body. The hallmark of the disease is the round to oval skin patches with a semblance to mild eczema. The color of the skin patches generally reacts with the climate such as during the hot summer months where the lesions are more prominent. Dry and scaly appearance are more prominent during the winter season resulting from a dry air in the inside environment.
The lesion in Pityriasis Alba may sometimes itch and the lesion basically passes through three clinical stages such as:
- The first stage is characterized by raised lesions with mild reddish discoloration which may not be noticeable at all
- The second stage is characterized by raised lesions with color that is rather pale
- The third stage of the lesion is described as flat and smooth skin patches with color that is pale
The characteristics of the individual lesion are as follows:
- The shape of the plaque is round or oval or may be irregular
- The color of the lesion may be in red, pink or may be the color of the skin
- The lesions appear in multiple about 4 to 20 numbers of lesions or may be more
- The size of the lesion varies although the usual is about 1cm to 4cm in diameter
- The texture of the affected skin may be fine or may be scaly
- The borders of the rash are usually not visible
- The color of the skin patches is light that it may sometimes seem to blend with the normal and healthy skin
The lesion in Pityriasis Alba has different variants which are classified according to the characteristics of the lesions. The variants of lesions in Pityriasis Alba are as follows:
Extensive pityriasis alba
Extensive pityriasis alba is characterized by lesions that are less erythematous with scaling that is rather few. This variant of Pityriasis Alba is often asymptomatic and often seen on the trunk than in the face. The distribution of the lesion is widespread and symmetrically involves the skin.
Pigmenting pityriasis is described with a core that is bluish in color and the surrounding skin is pale. The skin patches are limited to the face only and are usually connected with dermatophyte infection. The surrounding skin of the core is described as a scaly halo of different sizes or width.
Pityriasis Alba Causes
The exact cause of Pityriasis Alba remains unclear. It is a self-limiting disease without an infectious agent being clearly recognized.
Atopic dermatitis is mostly implicated in the skin disorder to which Pityriasis Alba is considered a mild form. The connection between atopic dermatitis and Pityriasis Alba is based on the reported number of patients who previously suffered from atopic dermatitis prior to the onset of Pityriasis Alba. It is then theorized that patients who experienced atopic dermatitis are more prone to developing Pityriasis Alba.
Malassezia yeast is also theorized to cause Pityriasis Alba. The onset of the disease is believed to be secondary to the substance being produced by the yeast known as pityriacitrin which act as the natural sunscreen of the body.
Iron deficiency anemia is also included in the theory behind the etiology of Pityriasis Alba. The theory is based on the reported cases of patients who experienced anemia prior to the onset of hypopigmentation. This, however, is considered to be coincidental owing to the small percentage of reported cases.
A family history of Pityriasis Alba is also considered to predispose an individual from Pityriasis Alba. However, this claim remains unclear.
Several factors are also considered to contribute to the incidence of Pityriasis Alba. An excessive and prolonged and unprotected exposure under the sun is believed to contribute to the onset of Pityriasis Alba. Another factor considered is the poor hygienic practice of an individual where infrequent bathing is theorized to cause the disease. Children who frequent hot baths are believed to be more prone to developing Pityriasis Alba. Environmental factor is also another factor believed to influence the incidence of the disease.
Pityriasis Alba requires no treatment as the skin lesions generally resolves spontaneously. Treatment may be given to hasten the improvement of the appearance of the disease and usually depends on the preference of the patient.
Topical steroids are the usual treatment for Pityriasis Alba. A weak steroid is usually prescribed to manage the symptom of itchiness and erythema. This method of treatment however, is for limited use and not for long-term treatment.
Simple emollients are also beneficial in reducing skin dryness and scaling, particularly Pityriasis Alba on the face.
Pimecrolimus cream and Tacrolimus ointment are both found to be beneficial in managing Pityriasis Alba.
Laser treatment is considered to be an effective treatment against Pityriasis Alba although this method requires repetition until the lesions have cleared.