Differential Diagnosis for Green Discoloration Under the Nails
- Single Most Likely Diagnosis
- Pseudomonas aeruginosa infection: This is a common cause of green discoloration under the nails, particularly in individuals with poor hygiene, nail trauma, or exposure to contaminated water. The green color is due to the production of pyocyanin, a pigment produced by the bacteria.
- Other Likely Diagnoses
- Fungal infection: Fungal infections such as onychomycosis can cause discoloration of the nails, including greenish tint, especially if the infection is caused by certain species of fungi.
- Nail polish or dye: Residual nail polish or dye can cause green discoloration under the nails, especially if the polish or dye contains certain pigments.
- Copper exposure: Exposure to copper, such as through handling copper coins or working with copper pipes, can cause green discoloration under the nails due to the deposition of copper ions.
- Do Not Miss Diagnoses
- Arsenic poisoning: Arsenic poisoning can cause a range of symptoms, including green discoloration of the nails. This is a potentially life-threatening condition that requires prompt medical attention.
- Heavy metal poisoning: Exposure to other heavy metals, such as copper or mercury, can also cause green discoloration under the nails and may be associated with systemic toxicity.
- Rare Diagnoses
- Wilson's disease: This is a rare genetic disorder that affects copper metabolism and can cause green discoloration under the nails due to the accumulation of copper in the body.
- Melanonychia: This is a rare condition characterized by the deposition of melanin in the nails, which can cause greenish or bluish discoloration.
- Subungual melanoma: This is a rare type of skin cancer that can cause greenish or blackish discoloration under the nails. Although rare, it is a potentially life-threatening condition that requires prompt medical attention.