Eczema, also known medically as atopic dermatitis, is a chronic inflammatory condition of the skin. It is not a single disease but a group of conditions that cause dry, itchy, and inflamed skin. The most common form is atopic dermatitis, which tends to begin in early life but may persist into adulthood. Symptoms include intense itching, redness, scaling, weeping in acute phases, and thickened, rough skin in chronic stages. The disease course is variable, with periods of flare-ups and relative calm. Eczema affects millions worldwide, especially in children, with prevalence estimates up to around 20% in high-income countries among children and ongoing disease in a portion of adults.
Why Does Eczema Occur?
The exact cause of eczema is complex and not fully understood, but scientific evidence identifies multiple interacting factors. A key component is skin barrier dysfunction: the outer layer of the skin fails to effectively retain moisture and protect against irritants, allergens, and microbes. This barrier defect allows environmental triggers to penetrate more easily, provoking inflammation. Genetic factors contribute; for example, mutations in genes such as filaggrin, which is crucial to skin barrier structure, are associated with more severe disease.
Immune system dysregulation also plays a central role. In eczema, immune responses are skewed toward inflammation, with immune cells releasing signalling molecules that promote redness, itching, and swelling. Environmental factors — including irritants, allergens, microbes, stress, and climate — further influence disease onset and severity by interacting with both barrier and immune systems.
How Does Eczema Present Clinically?
The most prominent symptom of eczema is pruritus, or itching, which can be severe and persistent. In acute stages, the skin may appear red, swollen, and inflamed, sometimes with small blisters that can ooze fluid. As the condition becomes chronic, repeated scratching leads to thickened skin, increased skin markings, and dryness. The distribution of eczema varies with age. Infants often develop lesions on the face and extensor surfaces, while older children and adults more commonly experience eczema in flexural areas such as the elbows, knees, neck, and wrists.
Eczema is not an infectious disease and cannot be transmitted from one person to another.
How Is Eczema Diagnosed?
Diagnosis of eczema is primarily clinical, meaning it is based on a careful physical examination and a thorough review of the patient’s medical history rather than on a single definitive laboratory test. Healthcare providers assess key symptoms such as persistent itching and a chronic or recurrent rash, and they also consider whether there is a personal or family history of eczema, asthma, or other allergic conditions. Particular attention is given to the typical distribution of lesions, which often involve flexural areas such as the creases of the elbows and knees. In addition, clinicians evaluate how long the symptoms have been present and the severity and persistence of itching.
Can Dermatoscope Detect Eczema?
In eczema, dermatoscopy does not reveal a single disease-specific pattern. Instead, it helps clinicians recognize characteristic but non-exclusive features that support a clinical diagnosis. Common dermatoscopic findings in eczematous skin include diffuse or patchy redness caused by dilated superficial blood vessels, fine white or yellowish scales reflecting abnormal keratinization, and an ill-defined vascular pattern. In chronic eczema, dermatoscopy may show accentuated skin lines corresponding to lichenification. During acute phases, serous crusts or micro-erosions can sometimes be observed.
Are There Different Types of Eczema?
Although atopic dermatitis is the most common type, eczema includes several related conditions. These include contact dermatitis caused by exposure to irritants or allergens, dyshidrotic eczema characterized by small blisters on the hands or feet, nummular eczema presenting as coin-shaped lesions, seborrhoeic dermatitis affecting oily skin areas, and chronic hand eczema. Each type has distinct triggers and clinical patterns, but all involve skin inflammation and barrier dysfunction.
What Factors Trigger or Worsen Eczema?
Many factors can provoke eczema flare-ups or make symptoms worse. These include environmental irritants such as harsh soaps, certain fabrics, fragrances, and chemicals, all of which can further strip moisture from the skin or provoke immune responses. Allergens (e.g., dust mites, pet dander), extreme temperatures or dry air, and microbial colonisation can also trigger inflammation.
Psychological stress is recognized as a trigger that can worsen eczema, likely by altering immune function and increasing inflammatory responses. Stress-related flare-ups can create a cycle where itching and scratching heighten both physical and emotional distress.
Other common triggers include sweating or heat, cold and dry climates, infections, and in some cases, food sensitivities that exacerbate immune activation.
How Can Eczema Be Managed?
Although eczema cannot be permanently cured, it can be effectively managed. Basic skin care is essential and includes regular use of moisturizers to support the skin barrier and gentle bathing practices. Avoiding known triggers is equally important. During flare-ups, topical anti-inflammatory medications are commonly prescribed to control symptoms. For moderate to severe disease, systemic treatments or targeted biologic therapies may be considered under specialist supervision.