Atopic dermatitis, or eczema, is a chronic inflammatory skin condition that causes intense itching, redness, and swelling. This condition involves an overactive immune system response and a compromised skin barrier, allowing moisture to escape and irritants to enter. Eczema presentation changes significantly over a person’s lifespan, with distinct characteristics in infancy, childhood, and adulthood. These variations are observed in the location of the rash and the physical appearance of the lesions.
Eczema in Infants
Eczema in infants often appears between one and six months of age. The rash primarily affects the face, cheeks, chin, forehead, and scalp. The diaper area is usually spared due to the protective moisture in that region.
The rash may also involve the extensor surfaces of the limbs (the outer aspects of the arms and legs). Lesions are generally red patches or small bumps that may become scaly. A common finding is weeping or oozing, where clear fluid leaks from the affected skin and dries into a crust.
Eczema in Childhood
The pattern of eczema shifts as a child grows, typically from age two until adolescence. Lesions begin to concentrate in the flexural creases of the body, such as the inside of the elbows and the backs of the knees. Other frequently affected areas include the creases of the wrists, ankles, and neck.
The skin lesions often appear drier and more papular compared to the weeping lesions seen in infants. Constant scratching from intense itching can lead to thickening of the skin, a change known as lichenification.
Eczema in Adulthood
Eczema that persists into or first appears during adulthood often becomes more localized. While some people experience the continuation of the flexural pattern from childhood, new areas are frequently involved. Hand eczema, affecting the palms and backs of the hands, is a common presentation.
The face and neck are also frequently affected, with the delicate skin of the eyelids being a common site for inflammation. Adult eczema tends to present with prominent dryness, scaling, and hyperpigmentation. Repeated scratching often results in significant lichenification, where the skin becomes leathery and thick.
Acute Versus Chronic Skin Presentation
The appearance of eczema lesions can be classified by their duration and severity, independent of the person’s age. This classification helps describe whether a rash is a sudden flare-up or a long-standing issue.
Acute Eczema
Acute eczema represents a sudden, severe inflammatory episode. Skin affected by acute eczema is typically intensely red and swollen (edematous). A hallmark of the acute phase is the presence of small, fluid-filled blisters (vesicles) that rupture. This results in a weeping or oozing discharge. This fluid then dries, forming a crust, which is a clear sign of an active, wet flare.
Chronic Eczema
In contrast, chronic eczema describes the changes that occur in the skin from long-term, persistent inflammation and repeated scratching. The skin develops a thick, leathery texture with exaggerated skin markings, a process medically termed lichenification. The chronic stage is often characterized by extreme dryness, scaling, and fissuring, where small cracks appear in the skin. Chronic lesions, unlike acute ones, are typically dry, scaly plaques rather than weepy blisters. A person can experience acute flares superimposed on areas of chronic skin changes.