DISCUSSION
This problem—chronic paronychia (also known as chronic candidal paronychia)—is not well known outside derm circles. It's even a bit of a mystery within the specialty, although we see it often enough to become comfortable with its diagnosis and treatment.
Here is what we know about it: Separation of the cuticle from the underlying nail plate appears to be the initial insult, with bacteria (candida) and food particles subsequently becoming trapped in the space and provoking an inflammatory response. There is often a history of excessive wetting and drying of the hands. The condition is rarely painful, but initially it can make the area sensitive to touch. The women who present with it—we virtually never see it in men—are usually middle-aged.
Primary care providers confronted with chronic paronychia often prescribe terbinafine for "fungal infection," but this never works because fungi are not involved. Some consider candida to be a type of fungus; however, for practical purposes, it is quite different. It causes completely different disease, is grown on totally different media in the lab, and requires special treatment. Terbinafine, an allylamine, has little if any activity against candida.
It should be noted that in many cases, the infectious component of chronic paronychia is minimal to absent. Therefore, the thrust of treatment is aimed at healing the damaged cuticle and helping it to reattach to the nail plate. This eventually resolves the problem, as the dystrophic nail will grow out and be replaced by healthy, normal-looking nail. Adding an imidazole cream to the treatment regimen will eliminate any suspected organism.
For this patient, I prescribed a month-long course of betamethasone/clotrimazole ointment to be applied twice daily. At follow-up, reconnection of the cuticle to the nail plate was noted, along with complete resolution of the modest redness. The nail was still dystrophic distally but clearing proximally. It should be clear within four to five months.
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