Skin Tests

Skin tests may be performed to diagnose skin allergies, food allergies, bacterial or fungal skin infections, and other diseases. Skin tests are also performed to differentiate between malignant (cancerous) cells and benign (noncancerous) growths.

• Patch testing. Patch tests are used to help diagnose skin and food allergies. Identified allergens are applied to the skin with adhesive patches and left for a period of time. The skin is then examined for any reaction. Other variations of this testing include prick tests and intradermal tests where allergens are applied to the skin or just under the skin with a needle. Download patch testing guidelines at CHOP.

• Skin biopsy. A skin biopsy is the removal of skin for laboratory analysis. The sample of skin may be removed with a scalpel or a cylindrical punch, after local anesthesia. Skin biopsies are performed to diagnose skin cancer or benign skin disorders.

• Culture. Skin, hair, or nails may be cultured to detect bacteria, fungi, or viruses.