onychodystrophy (nail dystrophy)

Introduction

Dystrophy of the nails.

Etiology

• onychomycosis (< 50%)
• thyroid disease
• parathyroid disease
• peripheral vascular disease
• Raynaud's disease
• anemia
• onychodystrophia mediana canaliformis
• psoriasis
  • more common in patients with psoriatic arthritis
• chronic nail trauma
• aging

Clinical manifestations

• thick, yellow, crumbling toenails

Laboratory

• KOH scraping, microscopic exam for septate hyphae of dermatophytosis
• fungal culture for dermatophytosis
  • collect subungual debris from beneath the nail to avoid a false-negative culture

Management

• treat underlying disorder
• do not treat with antifungals unless onychomycosis identified

More general terms

• nail disease

More specific terms

• onychodystrophia mediana canaliformis (tic habit)

Additional terms

• onychomycosis