• Age of onset (about half the patients present before the age of 20)

• Whether or not it runs in the family (familial in 36% of cases)

• About other autoimmune disorders (hypothyroidism, hyperthyroidism, thyroiditis, Addison’s disease, diabetes mellitus, pernicious anaemia).

• Hypopigmented patches (Fig. 160.1) that are distributed symmetrically; sometimes the border may be hyperpigmented. The distribution often includes wrists, axillae, perioral, periorbital and anogenital skin

• White hairs in the vitiliginous area

• Some spontaneous re-pigmentation in the sun exposed regions (in a third of cases).

• Look at the scalp for alopecia and white hair.