Green Nails

Bacteria are not capable of attacking a healthy nail plate. The Gram-negative bacterium Pseudomonas aeruginosa may colonize the dorsal or ventral nail plate under propitious conditions, such as chronic paronychia or onycholysis. The presence of Pseudomonas is revealed by a characteristic green-black nail pigmentation due to pyocyanin staining . Topical application of a few drops of diluted bleach or chlorhexidine solution two or three times a day clears the pigmentation in a few weeks. Administration of systemic antibiotics is unnecessary.