ABSTRACT
Diagnosis of melanonychia striata is one of the most difficult aspects of clinical dermatology. Melanoma is feared in most situations; however, melanoma of the nail apparatus is rare (about 1 % of all cutaneous melanomas). The clinical presentation of early nail apparatus melanoma-longitudinal pigmentation-is shared by many other clinical processes with much more favourable outcomes, such as nail apparatus naevus or lentigo, drug-induced pigmentation, subungual haemorrhage and ethnic-type nail pigmentation. The ‘gold standard’ of diagnosis remains the pathological examination of the nail matrix biopsy, but the biopsy procedure is usually painful and often results in nail dystrophy.
