Twenty-nail dystrophy

What is twenty-nail dystrophy?

Twenty-nail dystrophy is also known as ‘trachyonychia’. It could be said that twenty-nail dystrophy is widespread trachyonychia involving all 20 nails. The condition is characterised by longitudinal ridging (alternating elevation and depression), pitting, loss of lustre, and roughening (similar to sandpaper) of the nail surface.

What are the signs and symptoms of twenty-nail dystrophy?

Twenty-nail dystrophy most commonly occurs in childhood. In one study the condition was most evident in young males in the 10-20 year old age group (52%). Slight nail abnormalities may be evident at birth with the condition slowly progressing over the years to cause changes in the texture of fingernails and toenails. Typical signs and symptoms include:

• Nails become grubby, rough and brittle
• Some nails may become distorted
• Nail examination shows longitudinal ridging, pitting, roughening and splitting
• Nails lose their lustre and may change to a muddy, greyish-white colour (sand-blasted appearance)

What causes twenty-nail dystrophy?

The cause of twenty-nail dystrophy is unknown but in some cases it appears to be associated with other skin conditions such as lichen planus, eczema, psoriasis and alopecia areata. In some cases an autosomal dominant pattern of inheritance has been found; in one report twenty-nail dystrophy occurred in 4 males in 3 successive generations. Other cases of twenty-nail dystrophy are of unknown origin and begin gradually in early childhood. These cases tend to be self-limiting and may resolve slowly with age.

What treatment is available for twenty-nail dystrophy?

There is no specific treatment for twenty-nail dystrophy. It is a very difficult condition to treat and often results are unsatisfactory. Some treatments that have been tried include:

• Griseofulvin and other oral antifungal agents
• Systemic, topical and intralesional corticosteroids
• Topical PUVA