The Centers for Disease Control and Prevention (CDC) has reported a significant increase in the incidence of the skin condition urticarial pigmentosa in children younger than 4 years old in the United States.
The report, released Wednesday, says there have been 632 reported cases of urticarias in children aged 4 to 16, compared to 431 cases in 2014.
The increase has been attributed to the introduction of new medications, the report says.
According to the CDC, urticaris is an autoimmune condition in which the immune system attacks the skin and destroys its natural protective coating.
In urticarias, the immune response is triggered by the presence of a toxin or a protein that attacks the outer layers of the cells of the hair follicle.
It is often a mild case of dermatitic dermatitis, which is defined as a condition that is caused by an allergy to a substance or a condition in the body, the CDC said.
The new report notes that the incidence increased in children who were born between January 1, 1981, and December 31, 2015, with an average of 4.4 cases per 100,000 people.
The number of reported cases rose from a low of 3,907 in 2014 to 632 in 2016, the most recent year for which data is available.
The CDC said there have also been an increase in infections of uricaria pigmentosae, a new form of uriticaria pigmentosis, as well as in urticarium pigmentosa, a more severe form.
Urticaria is an inherited condition that can cause scarring, ulcers, and other skin disorders.
Urticaria can cause more severe cases, and urticarian pigmentositis, an autoimmune skin condition, is more common in older adults.
Urticarium is caused primarily by an enzyme, uricosidase, that is found in the hair.
It also is a protein.
It is normally produced by hair follicles in the skin, but when uricicoside is added to other cells, the enzyme can be turned into uricidase.
The result is a type of autoimmune skin disease, the skin’s immune system attacking the hair, the disease’s cause.
In children younger, urticaria is most common, affecting about 3.5 percent of the population, the Centers for Diseases Control and Preventives said.
The condition is more commonly diagnosed in children in the same age group as those affected by urticario pigmentosa.
In children who are more likely to have urticarians, they tend to have a greater frequency of symptoms, the researchers said.
Urticarian pigmentosa can cause eczema, acne, hair loss, and itchy skin.