Fungal Viridionychia: Onychomycosis-Induced Chloronychia Caused by Candida parapsilosis-Associated Green Nail Discoloration

Abstract

Green nail syndrome is a form of chromonychia, discoloration of the nail plate, that describes fingernails or toenails that are green in appearance. Bacterial-associated green nail syndrome, referred to as chloronychia, is most common; however, fungal and polymicrobial etiologies have been reported. Two 70-year-old women presented with green discoloration of their nails for over five months; both women had prior unsuccessful treatments and were referred for further evaluation and treatment. The affected nails were biopsied and cultured. Bacterial cultures did not yield any organisms; however, fungal cultures grew Candida parapsilosis after four weeks. Both women were treated with a topical alcohol-based solution and ketoconazole cream with improvement in their nail discoloration after two months. We introduce a term that specifically describes fungal etiology-associated green nail syndrome: viridionychia.

Two Cases of Superficial Fungal Infection Caused by Non-Albicans Candida Species Manifest Greenish-black Discoloration

“…The greenish-black discoloration only appeared in the right thumbnail, but not in other nails. Although such dark discoloration by C. parapsilosis has been reported previously, 32 the 33 which may explain the dark colored lesions in this case.…”

“…that are similar to Case 2. [32][33][34][35][36][37][38][39][40] Of note is fungal melanonychia, a rare nail disorder that presents as a longitudinal dark pigmentation in the nail plate. The causative Candida-associated fungal melanonychia were Candida albicans and NCAC.…”

“…[33][34][35][36][37][38][39][40] These isolated Candida were considered to be the cause of the discoloration rather than a colonized status. 41,42 In addition, some researchers have even introduced a term, viridionychia to specifically describe fungal etiology-associated green nail syndrome, 32 which differs from chloronychia with bacterialassociated green nail syndrome. Interestingly, the proposed viridionychia term was based on a fungal nail infection caused by Candida parapsilosis.…”

Green Nail Syndrome Treated with Ozenoxacin: Two Case Reports

“…syndrome, including chloronychia and viridionychia, is mainly due to Pseudomonas aeruginosa, characterized by green discoloration of the nail plate. However, also other bacteria such as Citrobacter braakii could be involved in this condition [9][10][11]. Although the diagnosis of GNS is mainly clinical, bacterial culture should always be performed to identify non-Pseudomonas bacteria and provide a complete antibiotic resistance profile.…”