ABSTRACT
Introduction@#Pseudomonas aeruginosa is an opportunistic, gram-negative bacillus that can contaminate skin or open wounds to cause skin infections that are historically difficult to manage. The pathogenesis of green nail syndrome (GNS) begins with hyperhydration (occlusion, sweating, maceration) or destruction (microtrauma, dermatitis) of the epidermis thus disrupting the physical barrier, leading to the colonization and proliferation of P. aeruginosa. This case explores the off-label use of nadifloxacin, a fluoroquinolone approved for acne and bacterial skin infections in some countries, to treat a case of GNS. @*Case Report@#This is a case of a 31-year-old Filipino female who presented with a four-month history of green discoloration of the lateral portion of the right thumbnail with a medical history of antiphospholipid antibody syndrome and rheumatoid arthritis. Clinical examination showed a dystrophic thumbnail with greenish discoloration, erythema and swelling around the base of the cuticle, and distal onycholysis. Laboratory findings revealed co-infection of P. aeruginosa and Candida parapsilosis. The patient was effectively treated with topical nadifloxacin and oral fluconazole.@*Conclusion@#This case highlights the possibility of fungal and polymicrobial infections in GNS and suggests a novel, easy-to-use, and cost-effective alternative treatment to GNS secondary to P. aeruginosa in the form of topical nadifloxacin.