What does the presence of greenish nails typically indicate?

• A. A fungal infection
• B. A bacterial infection
• C. A viral infection
• D. Mineral deficiency

Answer: (B)

The presence of greenish nails is typically indicative of a bacterial infection, particularly one caused by Pseudomonas aeruginosa. This bacterium can thrive in moist environments, such as under the nail or in the nail plate, and can lead to a characteristic greenish discoloration due to the pigments it produces. This discoloration is often accompanied by other symptoms such as a foul odor or pus, which further confirms the bacterial nature of the infection.

In contrast, a fungal infection would usually result in changes such as yellowing or thickening of the nails, not a green color. Viral infections do not commonly manifest as discoloration of the nails, and mineral deficiencies generally present with different signs, such as brittleness or ridging, rather than specific color changes. Thus, the context of greenish nails is strongly aligned with bacterial infections, especially from Pseudomonas, making the identification correct.