Role of histopathology in vitiligo.

Vitiligo is in most cases diagnosed clinically, so obvious are the features of a well developed lesion of this disease. Other investigations are rarely required. However, occasionally vitiligo especially in its early evolving stage or in some of its localised expressions may pose diagnostic difficulties as the lesions are hypopigmented rather than depigmented and other differential diagnoses may be considered. The histopathological changes in vitiligo in sections stained with haematoxylin and eosin (H&E) are often very subtle and may be inconclusive. Special staining procedures like the Fontana-Masson staining may help in reaching a definite diagnosis. The DOPA reaction which demonstrates viable and functional melanocytes may also be used but is technically difficult to perform.