Psoriasis and Your Nails
Ronald Prussick, M.D., a dermatologist practicing in Rockville, Maryland, since 1995, is often the first person to tell patients about the connection between their psoriasis and the condition of their nails.
More than 35 percent of people with psoriasis will develop nail psoriasis. This high percentage, coupled with the fact that nail involvement is often indicative of severe psoriasis, has Prussick checking the nails of every patient who has or is suspected of having psoriasis.
In fact, examination of the nails can sometimes be the only way to diagnose psoriasis if skin lesions are not present or extensive.
Diagnosing nail psoriasis can be difficult, however, because biopsies of the nail are painful. In addition, many of the symptoms point at other conditions, including anemia, thyroid problems, onychomycosis (fungal infection) or a deficiency in zinc, biotin, calcium, protein or vitamin A.
Toenail psoriasis, for example, is commonly misdiagnosed as a fungal infection, and horizontal ridges (known as Beau’s lines) can be a sign of a zinc deficiency. These ridges are present in a person with nail psoriasis because the structures that support and grow the nail – the nail bed and nail matrix – are weak or have suffered an injury resulting in the abnormality.
Prussick says the key with all types of psoriasis is to be gentle. “If you scratch it, it could get worse because an injury can lead to spreading,” Prussick says, referring to the Koebner phenomenon, in which even small traumas to the skin, including friction and rubbing, can intensify psoriasis.
“Aggressive cleaning under the nail can make onycholysis worse and open the nail up to bacterial and fungal infections,” Prussick adds. That explains why the relief I got from removing the buildup under my nails from onycholysis was over so quickly.
What Your Nails can Tell You About PsA
When it comes to psoriatic disease, the nails also can be a sign that something even bigger could be brewing.
Evan L. Siegel, M.D., a rheumatologist who shares a practice with Prussick in Rockville, Maryland, believes the main point to take away is that for patients with psoriasis, nail involvement is a risk factor for developing PsA.
“A person who has nail psoriasis has a threefold increased risk for developing PsA, which translates to around 80 percent of people with PsA having nail involvement,” says Siegel.
He also explains that paying attention to what your nails are trying to tell you can mean the difference between minimal and serious, irreversible damage to the joints. “When treating skin psoriasis, the skin that grows back is typically normal, healthy skin,” he says. “But with PsA, once the [joint] damage is done, it is permanent.”
Siegel also echoes Prussick about the Koebner phenomenon: He believes trauma to the nail, surrounding skin and joints may play a role in the development of PsA. Siegel says inflammation below the nail matrix in the distal interphalangeal joint (the first knuckle from the top of the finger) can contribute to nail symptoms. Protecting these areas from injury and trauma (for example, when using the nail as a tool) and from stress (such as straining to open a jar) can help prevent the progression of nail psoriasis and heal the nail, Siegel says.
7 Nail Psoriasis Symptoms
- Pitting – shallow or deep holes in the nail plate
- Deformation – changes to the normal shape of the nail plate
- Thickening of the nail plate – cause of a “heavy” sensation in the nail
- Onycholysis – separation of the nail plate from the nail bed
- Discoloration – unusual nail colorations, such as yellow-brown, that may look like a fungal infection
- Onychomycosis – fungal infection of the nail unit
- Beau’s lines – horizontal ridges in the nail plate