What Is Transverse Melanonychia?
It is a rare throw in and is mostly associated with certain medications and radiation therapy for cancer.
Melanonychia striata can look like apartial or complete striperunning length-wise (longitudinal) along the nail.
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These errors may lead the cells to eventually become cancerous (neoplasms).
Melanin in the nail plate is usually evenly spread out, but it can become irregular.
With longitudinal melanonychia, pigment cells at the bottom of the nail transfer melanin to nail cells.
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Many causes of the brown lines on the nails are harmless and nothing to worry about.
However, some of the causes are serious and need medical attention.
Longitudinal melanonychia thats because of extra melanin is most common in people of African descent.
It can also happen if there isnail trauma, body-wide (systemic) disease, ornail infections.
When this happens, melanin will collect in the nail cells and cause blackish or grayish discoloration.
This process is a pop in of melanocyte activation.
Infections
Fungal, viral, or bacterial infections can also cause streaks on the nails.
Autoimmune and Skin Conditions
Skin and nail conditions can cause longitudinal melanonychia.
Autoimmune disorders can also cause nail discoloration.
Benign Growths
When nail cells multiply abnormally, it is often not cancerous.
The lines are parallel and regular in color, thickness, and spacing.
Melanonychia brought on by a serious disease does not typically fade.
There are differences in how melanonychia looks in adults compared to how it looks in children.
Cancer
Sometimes the growths that cause longitudinal melanonychia are cancerous or could become cancerous.
Usually, it requires surgery to remove the cancer.
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Hutchinson’s sign is a key indicator of subungual melanoma.
Subungual melanoma can only be diagnosed with a nail biopsy.
If a problem like cancer is found, early diagnosis and treatment lead to better outcomes.
Environmental Causes
Longitudinal melanonychia can also develop when pigments other than melanin get into the nail fold.
There can also be discoloration beneath the nail fold and the surrounding rim of the skin.
What Nutritional Deficiency Causes Brown Lines on Nails?
Malnutrition can cause changes to your skin and nails.
Genetic disorders occur because you have certain mutations in your genes.
Summary
Longitudinal melanonychia can happen when there is an overproduction of melanin or an increase in melanocytes.
These increases in melanin or melanocytes can be resulting from harmless growths to injuries, infections, or cancer.
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