Nail evaluation in internal diseases: An indispensable exercise

Nails are the structures without any vital functions, but their diagnostic significance cannot be undermined. Nail unit constitutes the nail plate, nail bed, and nail folds which exhibit signs of the nail unit and internal disorders. Most nail changes are nonspecific, but some of them have high diagnostic significance. Many such changes have been described since the historic times, and many have been discussed in the recent literature. Diseases of the nail units such as infections may also indicate the presence of immunosuppression or diabetes. Interpretation of the nail changes requires an amount of expertise which any physician can obtain by careful observation. This article emphasizes the important nail signs in internal disorders