Brief Answer:
Possible fungal nail infection

Detailed Answer:
Hello,

Thank you for using HCM to post you health issue.

I saw carefully your pictures.
It looks like a fungal infection. Unless you have any other particular problem that you know you suffer from, or take any medicine that may cause that discoloration.

So, most possible cause is a fungal infection. The lesion is called "Oil nail discoloration".

Something you may try, that has proven to be helpful, and that you can buy over the counter is Ciclopirox solution.

Use it as directed in the box. Avoid using nail polish or other nail cosmetic products.

Do not take a bath, shower, or swim for at least 8 hours after applying Ciclopirox topical solution.
Now please don't panic but actually it may take up to 6 months or longer before you notice that your nails are getting better.

Hope this is helpful.
Let me know if you need more clarifications.

Regards,

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