ORLANDO – at the ODAC Dermatology, Aesthetic, & Surgical Conference.
Dr. Hinshaw, professor of dermatology at the University of Wisconsin, Madison, reviewed several disorders and provided guidance on diagnosis, and achieving the best outcomes for patients.
Dr. Molly Hinshaw
Retronychia: This is an ingrowth of the proximal nail plate into the proximal nail fold, which mimics chronic paronychia, or nail inflammation. A key to the diagnosis is elevation of the proximal nail plate, Dr. Hinshaw said, along with yellowing of the nail. In some cases, a second or even third nail can be seen growing under the nail plate, she said.
“There has been traumatic lifting of the central portion of the nail plate over the matrix,” she explained. “The body thinks it needs to make a new nail plate, so it starts to do that while the primary nail plate has not yet let go.”
Sometimes, treatment with topical steroids will be effective, she said, but there might be secondary changes that require further treatment. She referred to a systematic review and a suggested treatment algorithm for retronychia, published in 2022, which can be helpful. “Even though this entity is not very well studied, there are at least some consensus approaches that the proximal nail plate needs to be removed, if not the entire nail plate,” she said.
Onycholysis: Essential to treatment of this disorder – separation of the nail from the nail bed – is knowing when it is secondary to another issue, whether it is a fungal infection, psoriasis, or tumor under the nail.
When a patient has primary onycholysis “and there’s nothing else going on in the nail, remember to try retinoids,” Dr. Hinshaw said. She suggested clipping back the nail and treating the nail bed every night with tretinoin 0.025%. If the nail bed becomes irritated, patients can pause treatment for a few days, she said.
If onycholysis has been present for 6-12 months, it can become permanent. But she said she has had success treating patients who’ve had it for a year or even a little longer, “so what we don’t want to do is give up hope for patients.”
Pyogenic granuloma (PG) in the nail: These are benign vascular tumors that can mimic more serious conditions, Dr. Hinshaw said. In adults, PG requires a histologic diagnosis, she said.
“So these all really should have a biopsy,” because of potential confusion with amelanotic melanoma or squamous cell carcinoma, she said, although in children, a biopsy is likely not necessary.
Treatment with topical beta-blockers can be effective for PG, she said, and avoids the scarring seen with surgical removal. “These are benign conditions – we want them to go away, but we want these patients to have a functional nail thereafter.”
Periungual or subungual warts: For these warts, which are alongside or under the nail, destructive approaches can cause scarring of the nail bed and are far from optimal, she said.
“We’d like to avoid that, of course.” Therefore, treatments such as lasers and liquid nitrogen “would be much further down, if at all, on my list,” she said.
Injections of the antiviral cidofovir, into the dermis right under the wart, can be highly effective, and one or two treatments is often enough, Dr. Hinshaw said. Sometimes, local anesthesia isn’t even needed for the injection, she said. “This is a wonderful option,” she added.
Dr. Hinshaw is co-owner and chief medical officer of Acure.