Isolated Nail Lichen Planus With Extensive Involvement: The Importance of Clinicopathologic Correlation and Response to Hydroxychloroquine.

Nail lichen planus is an uncommon inflammatory disorder that can occur as an isolated condition and may lead to permanent nail scarring when diagnosis is delayed. We present the case of a 50-year-old woman with progressive dystrophy affecting 16 fingernails and toenails, associated with pain and impaired ambulation. Clinical examination and onychoscopy raised suspicion of nail lichen planus, while repeated mycological studies were negative. Histopathological examination of a nail matrix biopsy confirmed the diagnosis. Treatment with systemic prednisone did not result in clinical improvement. Subsequently, hydroxychloroquine (200 mg/day) combined with topical 0.05% clobetasol led to progressive improvement over 12 months, characterized by decreased pain, reduced periungual inflammation, and growth of less dystrophic nail plates without evidence of further irreversible damage. This case emphasizes the importance of considering nail lichen planus in patients with multifocal nail dystrophy and negative mycological studies. Early clinicopathological correlation is essential for diagnosis and timely management. Hydroxychloroquine combined with topical clobetasol may be considered as a therapeutic approach in selected patients with inadequate response to systemic corticosteroids.