Infants who develop rashes on their arms and over their joints appear most likely to acquire the skin disease atopic dermatitis by age 3 years, according to an article in the May issue of the Archives of Dermatology, one of the JAMA/Archives journals.
Atopic dermatitis, which is characterized by recurrent scaling, redness and itchiness of the skin, has become more prevalent in the past 40 years, according to background information in the article. The condition usually arises in the first few years of life and is often associated with a family history of asthma and allergies. Despite infants' susceptibility to the condition, it is often difficult to diagnose atopic dermatitis in such young patients because it is difficult to determine if they are experiencing itching, one of the main symptoms.
Liselotte Brydensholt Halkjær, M.D., Copenhagen University Hospital, Denmark, and colleagues assessed the development and progression of atopic dermatitis in 411 infants born between August 1998 and December 2001 to mothers with a history of asthma. Almost half (48 percent) of the mothers had a history of atopic dermatitis as well. The infants were examined at age one month and again every six months or if their skin symptoms or respiratory symptoms worsened.
Of the 411 infants, 356 were followed through the entire study; 155 (44 percent) developed atopic dermatitis by age 3 years. The prevalence of the condition was highest at age 2.5 years for girls and 2 years for boys. The rashes of children who developed atopic dermatitis tended to begin on the scalp, forehead, ear, neck and cheek and then spread to the front of the legs, the back of the arms and the rest of the face and torso. Finally, the rash would reach the back of the legs and the front of the arms.
Early rashes on the arms and over the joints were most likely to predict the later development of atopic dermatitis, while rashes on the head and neck were associated with lower odds of progressing to the chronic condition. There was no association between early rashes in the diaper area and later atopic dermatitis.
