Melanonychia pigmentatio nigra vel fusca est normalis laminae clavi et potest apparere ut inventio communis in pluribus digitis apud populum Afro‑Caribbeum.
Cohors lata, pigmentatio profunda cum lineis irregularibus et extensione pigmenti in fibras periunguales, est signum melanoma.
Melanonychia is a black or brown pigmentation of the normal nail plate, and may be present as a normal finding on many digits in Afro-Caribbeans, as a result of trauma, systemic disease, or medications, or as a postinflammatory event from such localized events as lichen planus or fixed drug eruption.
Lineae inusitatae multiplices observantur. Melanonychia maxime benigna est, sed si in hoc gradu multae lineae irregulares sunt, biopsy considerari potest.
Multi aeger(e) melanonychiam praesunt, quae laminae unguis colorem brunneo‑nigrum affert. Causae coloris unguis frequentissimae a benignis ad graves, ut melanoma, variant. Cohors longitudinalis melanonychiae, sicut melanonychia, ex variis factoribus localibus vel systemicis derivari potest. Melanonychia is a very worrisome entity for most patients. It is characterized by brownish black discoloration of nail plate and is a common cause of nail plate pigmentation. The aetiology of melanonychia ranges from more common benign causes to less common invasive and in situ melanomas. Melanonychia especially in a longitudinal band form can be due to both local and systemic causes.
Melanonychia represents a brown to black discoloration of the nail plate that may be induced by benign or malignant causes. Two main mechanisms are involved in the appearance of melanonychias, i.e., melanocytic activation and melanocytic hyperplasia.
Muehrcke's lines
Cohors lata, pigmentatio profunda cum lineis irregularibus et extensione pigmenti in fibras periunguales, est signum melanoma.