Eczema Tests and Diagnosis

Eczema or dermatitis are generic terms that refer to an inflammatory skin condition. The problem is often inherited. Some sufferers experience symptoms sporadically. Others endure chronic forms of the rash. Differentiating eczema from other skin conditions requires seeing a healthcare provider for a proper diagnosis.

The Diagnosis Process

Physicians commonly perform a physical examination to evaluate the characteristics and extent of the rash. Some of the factors that positively identify the rash as eczema include the overall appearance and distribution of lesions, itching and irritation. In many instances, by looking at the rash and asking a series of questions, healthcare providers narrow the causative factor or factors contributing to the problem. Pertinent information leading to a diagnosis includes:

  • A family or personal history of allergies
  • Known chemicals, substances, or conditions that cause irritation
  • Where and when the symptoms first appeared
  • The duration of symptoms
  • Recent environmental changes that might include exposure to new compounds, foods, or other items
  • What conditions help or irritate the condition
  • A recent increase in stress levels

If suspecting an infection, a physician may look at a minute sample of the dry scales under a microscope. The magnified visual display helps determine if a fungus initiated the problem. When suspecting allergies, there are a number of additional tests that assist healthcare providers in the diagnosis process.

Complete Blood Count

This test requires withdrawing a small amount of blood from a vein in the arm using a syringe. Under a microscope, technicians locate and count the number of white blood cells called eosinophils. An elevated number of these special cells often means that the patient suffers from allergies. When allergies are the suspected cause of eczema, physicians may perform skin tests that attempt to identify specific allergens.

Skin Patch Test

The test entails wearing a special patch on the skin on which a sample of the suspected antigen is applied. One side of the patch has a mild adhesive that attaches to the skin similar to a simple bandage. In one to three days, the patient returns to the office where a healthcare provider removes the patch and evaluates the skin for a possible reaction.

Skin Prick Test

Typically performed on the forearms or the back, a healthcare provider marks the skin with a series of dots, depending on the number of allergens to be evaluated. At each dot, the physician places a drop of solution that contains a possible antigen. Using a needle, the skin is then lightly pricked to expose the immune system to the solution. A positive reaction occurs when redness and swelling appears.

Intradermal Test

Similar to the prick test, a healthcare provider cleanses and marks the skin. However, in this instance, the diluted antigen is injected just under the skin. Once again, if swelling occurs, the specific allergen caused a positive reaction.

Eczema Treatment

After diagnosing the condition as eczema, physicians may recommend or prescribe treatments based on what may have caused the symptoms. As dry skin is a major problems, OTC or prescription creams or ointments help increase and maintain adequate moisture levels. Antihistamines also reduce irritation and itchiness. If allergies are involved, physicians prescribe or recommend medications that also help minimize or eliminate symptoms.

Last Updated: June 14, 2016