Nail Abnormalities in Patients with Vitiligo
Researchers from Istanbul, Turkey noted that nail abnormalities (NAb) have been documented in various other autoimmune diseases associated with vitiligo, and suggested that the same should be apparent in vitiligo patients. With prior research on the topic being limited to a single report, they conducted a two-year study to determine the frequency and type of nail abnormalities in vitiligo patients compared to non-vitiligo control.
The researchers observed an increased incidence of NAb among those in the vitiligo group (78% exhibiting at least one nail abnormality) as compared to those in the control group (55%), but found no correlation between the presence of NAb and patient age or vitiligo duration.
The 3 Most Frequent NAb Observed in the Vitiligo Group:
Longitudinal ridging (42%)
Appears as a series of superficial, narrow,
longitudinal, parallel striations on the nail
Appears as white spots
Absent lunula (13%)
Absence of the lunula (the crescent-shaped white area at the base of the nail)
An absent lunula on the little finger is considered normal. However, small or no moons on the other fingers can indicate an underactive thyroid gland, as well as deficiency of vitamin B12 or iodine which feeds the thyroid gland.
Because research has shown the risk to develop autoimmune thyroid disease to be 2.5 times higher among those with vitiligo than in the normal population, if you notice a nail abnormality, you should check with your doctor about thyroid testing.
info from here