Yellow Nail Syndrome
With yellow nail syndrome, the nails thicken and new growth slows down. This results in a yellowish discoloration of the nails. One of the most common causes of yellow nails is a fungal infection. As the infection worsens, the underside of the nail may recede, and the nails may thicken, crumble, fail to form the cuticle, and the nail may peel off in places.
Yellow nail syndrome is often a sign of respiratory illness, such as chronic bronchitis. It can also be linked to swelling of the hands (lymphedema). In rare cases, yellow nails can indicate a more serious condition such as a serious thyroid condition, lung disease, diabetes, or psoriasis.
Bluish Nails
The medical term for blue nails is cyanosis, which can be a sign of a variety of disorders and should be investigated. While very cold temperatures can temporarily slow blood flow to the skin causing a bluish color, this color should disappear as soon as you warm up. In Raynaud’s disease, the fingers and toes turn white, then blue, and may become numb or painful when exposed to cold. The problem is simply excessive sensitivity of the nerves that control blood flow in the small arteries of the fingers, toes, nose, and earlobes.
Green Nails
Green nails are the result of a pseudonomas infection, which is usually caused by the environment. This means that those with already weak immune systems are very susceptible to this type of nail infection, which often turns the nail green.
Pitted Nails
Small pits or pits in the nails are common in people with psoriasis, which is a condition characterized by scaly patches on the skin.
It may also be related to connective tissue disorders, such as Reiter’s syndrome, alopecia areata, an autoimmune disease that causes hair loss.