Clearly explainedEvidence-based guidance

First assessment

How are white patches assessed?

Observation is useful, but a dermatological examination is needed to distinguish vitiligo from other causes of reduced pigmentation.

In brief

Key points

  • Record when the patch appeared
  • Use comparable photographs
  • Mention scaling or itching
  • Wood’s light can help
  • Tests are chosen individually
01

Clinical examination

The clinician reviews the shape, colour and distribution of the patches, their development and any associated symptoms. Hair colour and changes elsewhere on the skin may also be relevant.

02

Wood’s lamp examination

In a dark room, Wood’s light can make depigmented areas and their borders easier to see. It supports, but does not replace, the complete clinical assessment.

View the Wood’s lamp at IDEALDERM
03

Additional tests

Blood tests, microscopy or other investigations are only useful when the history or examination suggests a specific differential diagnosis or associated condition.

Editorial basis

Editorial basis: AWMF S2k guideline on the diagnosis and treatment of vitiligo, register 013-093, version 2.0 dated 27 July 2026, valid until June 2031. Sources reviewed on 2 September 2026.

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