Chronic Paronychia Could Have a New Treatment

Chronic paronychia is probably a form of hand dermatitis associated with prolonged wet work, suggests a study in the Indian Journal of Dermatology, Venereology, and Leprology. It is among a series of recent studies that have determined that chronic paronchia is not an infection resulting from Candida, a genus of yeasts that is the most common cause of fungal infections. The distinction is important, because it may make a difference in how the condition is treated.

Chronic paronychia is a multifactorial inflammatory condition of the nail folds more commonly affecting women than men. Previous studies have established the connection between the condition and constant exposure to moisture and detergents. Contact allergy, food hypersensitivity and irritant reactions are also potential causes. Paronychia is characterized by disruption of the cuticle, which results in breakdown of the protective seal between the nail fold and nail plate, providing an entryway for environmental irritants, allergens and microbes.

The study authors posit that infection mainly plays a role in perpetuating the inflammation rather than being the primary pathogenic cause. “Candida has been the most frequently cultured organism in patients of chronic paronychia,” they wrote. “However, despite higher isolation rates, the etiological role of the fungus has not been established. It is regarded as a secondary colonizer as it disappears once the physiological barrier in the nail is restored.”

The study looked at 80 patients being treated at the outpatient department of dermatology, Jawaharlal Institute of Postgraduate Medical Education and Research (JIPMER), Puducherry, India, over two years between September 2012 and August 2014. Chronic paronychia was defined as absence of cuticle, with swelling and erythema of the proximal nail fold lasting more than six weeks. Patients with acute paronychia, chronic paronychia as a part of other dermatological disorders, or those who were already on topical steroids or oral antifungals during the past two weeks and pregnant and lactating women were excluded.

Nails from the most severely affected digits were examined by gentle scraping of the ventral portion of the proximal and lateral nail folds and by nail clippings from the affected nails. In addition, patients were also patch tested and prick tested with Candida antigen. Indian standard series antigens, and other additional antigens if required, were used for patch testing. There was female preponderance (66 patients, 82.5%), with the most common group affected being housewives (47 patients, 58.8%). Frequent washing of hands (64 patients, 80%) was the most common risk factor. Fungal culture was positive in 56.1% (41 patients), the predominant species cultured was Candida albicans (15 patients, 36.5%). Patch testing with Indian standard series was positive in 27.1% patients (19 out of 70 patients tested), with nickel being the most common allergen, possibly due to nickel being an ingredient in certain types of nail polish. Prick test with Candida allergen was positive in 47.6% patients (31 out of 65 patients tested).

“Prolonged wet work leads to loss of the protective cuticle of the nail and separation of nail fold from nail plate, forming a pocket-like structure which serves as a repository for secondary Candidal invasion,” the authors noted. “The presence of Candida leads to hypersensitivity which further accentuates the inflammatory process and is responsible for maintenance of the disease. Hence, while choosing treatment options for chronic paronychia, in addition to eradicating the fungus with antifungals, we should also treat the hypersensitivity with topical steroids or tacrolimus.”