While black lines on nails can be benign, such as freckle-like nevi or melanonychia, if these lines have the following characteristics, they may indicate subungual melanoma:
- Width greater than 3 millimeters.
- Rapidly widening over a short period.
- Triangular shape with a sharp tip.
- Nail plate damage.
- Black spots around the nail.
Melanoma is a rapidly progressing and potentially deadly skin cancer, so if you notice these symptoms, seek professional medical examination immediately.
Clubbing is characterized by upward curving nails and abnormal enlargement of the fingertips. It can be identified through a simple self-test:
- Place the nails of the index fingers together. Normally, a diamond-shaped gap should be visible. If the gap disappears, it may indicate clubbing.
Clubbing can be associated with various factors, including tissue hypoxia, endocrine disorders, or genetic factors, and may be related to several systemic diseases. Notably, about 75% to 80% of clubbing cases are linked to lung diseases, such as chronic lung abscess, severe bronchiectasis, or chronic empyema, and sometimes it can even be an early sign of lung cancer.
- Yellow Nails: May indicate a fungal infection, especially if the nails become thick and detach.
- Blue or Purple Nails: May indicate a lack of oxygen in the blood, possibly due to heart or lung diseases.
- Pitted Nails (Koilonychia): May be associated with iron deficiency anemia or other blood disorders.
Recommendation: If the color of your nails changes significantly, especially if persistent or accompanied by other symptoms, seek professional medical examination and diagnosis promptly.