Causes and Diagnoses

Causes and Diagnoses of Dermatitis Herpetiformis

The cause of dermatitis herpetiformis is a reaction to gluten that produces the immunoglobulin A (IgA) antibody. The antibody travels through the blood to the blood vessels under the skin and creates a rash.

Diagnosing dermatitis herpetiformis

A diagnosis of DH begins with a physical exam and discussion of your symptoms. Other tests may include:

• Blood tests: Your blood sample will be analyzed for antibodies created by your body in response to eating gluten.  
• Biopsy: A small sample of tissue may be taken and analyzed under a microscope for antibodies. A “punch” biopsy may be used to take a circular portion of skin and tissue next to the lesion. Fluorescent dye is used to identify the IgA antibody deposits that indicate sensitivity to gluten.