Causes and Diagnoses

Causes and Diagnoses of Psoriasis

The precise cause of psoriasis isn’t known, but it’s related to a malfunction of the immune system that causes skin to grow and shed at an abnormally fast rate. There is a genetic component to psoriasis, which means if you have it, there’s a good chance someone else in your family has psoriasis as well. Psoriasis is not contagious.

Many types of psoriasis have a trigger that sets off an episode. They include:

  • Stress
  • Strep throat
  • Respiratory infection, earache or bronchitis
  • Medication
  • Sunburn
  • Cold, dry weather
  • A cut or scratch

Diagnosing psoriasis

A diagnosis of psoriasis usually involves a physical exam and discussion of your symptoms and family history. If necessary, a biopsy (tissue sample) may be taken for examination under a microscope if there’s a question of whether an outbreak is psoriasis or eczema.

Diagnostic Tests

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