5. Grooves on the nails:
Horizontal lines on the finger nail surface are known as “Beau’s lines”, and can occur as a part of chemotherapy, due to any chronic illness, an old injury, or in the setting of Raynaud’s disease, when the fingertips have been exposed to cold temperature for long periods of time.
When the finger nails tend to undergo clubbing, they actually indicate something serious and chronic going on inside the body. Clubbing of nails is said to happen when the underlying tissue bed thickens and the fingertips grow rounded. The normal angle between the nail bed and the nail disappears. When such a thing happens, the reason could likely be some long-term disease such as liver cirrhosis, stomach cancer, lung ailments (especially those in which the host has been deprived of optimum oxygen consumption since long), heart ailments (in which there is a ventilation perfusion mismatch), polycythemia (when the blood becomes thick in consistency due to an overload of R.B.Cs), or inflammatory bowel disease.
7. Dark lines:
Dark vertical stripes (linear melanonychia) on the nails are at times naturally present in dark-skinned individuals. However, if it appears suddenly, it might indicate subungal melanoma. In this case, the dark stripes my change their color overtime due to variation in pigmentation. Moreover, the surrounding nail fold is also likely to darken. Fortunately in most of the cases of linear melanonychia, the underlying cause is negligible.
8. Red streaks:
If you notice any red or brown streak developing under the surface of your nail, it could be a ‘splinter hemmorhages’, which is actually the blood oozing out of a damaged underlying vessel. Splinter hemmorhages can occur due to nail trauma. It is also an important sign of endocarditis, lupus erythematosus and psoriasis.
9. Overgrown nails:
Overgrown thickened nails are a common consequence of fungal infection. Moreover, they also form a symptom of reactive arthritis and psoriasis. A condition known as ‘onychogryphosis’, in which the toe nails grow excessively long and resemble a ram-horn, must not be confused with the thickened nail occurring due to fungal infection. The latter mentioned scenario is of common occurrence in the old age group, in whom the nail overgrows as a response to long-term pressure.