Melanonychia striata longitudinalis. A case report

Area of Science:

• Dermatology
• Nail Biology

Background:

• Melanonychia strata longitudinalis is a nail condition characterized by pigmented bands.
• It results from increased melanin production in the nail matrix, often due to melanocyte changes.

Observation:

• A case study of a white patient presenting with melanonychia strata longitudinalis.
• The pigmentation was observed as a longitudinal, dark brown-tan-black band on the nail plate.

Findings:

• The nail pigmentation in this patient was attributed to epithelial hyperpigmentation.
• Crucially, there was no evidence of melanocytic hyperplasia, malignancy, or hormonal imbalance.

Implications:

• This case highlights that epithelial hyperpigmentation can mimic melanonychia strata longitudinalis in white individuals.
• It underscores the importance of differentiating causes of nail pigmentation to rule out underlying pathology.