FUNGAL INFECTION

 

Fungal Nail Infection (Onychomycosis)

What is it?

• A common infection of the toenails (sometimes fingernails) caused by fungi.
• Dermatophytes (e.g., Trichophyton rubrum) are the most frequent cause; yeasts and moulds can also be involved.

Symptoms

• Nail discoloration: Yellow, white, or brown patches.
• Nail thickening and brittleness.
• Distorted shape or lifting of the nail (onycholysis).
• Debris under the nail.
• Sometimes discomfort, pain, or mild odor.

Risk Factors

• Older age (slower nail growth, circulation issues).
• Diabetes, immunosuppression, peripheral vascular disease.
• Sweaty feet, tight shoes, repeated nail trauma.
• Walking barefoot in communal areas (bathroom, locker rooms).

Types

1. Distal lateral subungual onychomycosis – starts at nail edge.
2. White superficial onychomycosis – white patches on surface.
3. Proximal subungual onychomycosis – starts near cuticle, rare.
4. Total dystrophic onychomycosis – entire nail destroyed.

 

Diagnosis

1. Clinical Exam
   • Visual assessment of nail changes.
2. Dermoscopy (Onychoscopy)
   • Non-invasive magnified imaging for nails.
   • Key dermoscopic findings in fungal nail infection:
     • Jagged proximal onycholytic edge.
     • Longitudinal streaks or spikes.
     • Ruin appearance (irregular, crumbling nail plate).
     • Subungual hyperkeratosis.
     • White or yellow patches with clear borders.
   • Useful to distinguish fungal infections from psoriasis or trauma.
3. Lab Tests
   • KOH microscopy – detects fungal elements quickly.
   • Fungal culture – identifies organism, takes longer.
   • PCR tests – fast and highly sensitive.

Treatment

• Topical antifungals:
  • Ciclopirox, Amorolfine, Efinaconazole.
  • Best for mild/early infections.
• Oral antifungals:
  • Terbinafine (most effective) or Itraconazole.
  • Used for moderate to severe infections; require liver monitoring.
• Combination therapy: Oral + topical for better success.
• Debridement: Thinning or trimming by a professional.
• Laser or photodynamic therapy: Mixed evidence, newer options.

Prevention

• Keep feet clean, dry, and nails trimmed.
• Wear moisture-wicking socks and breathable shoes.
• Change socks daily, alternate shoes.
• Use antifungal powders if prone to sweaty feet.
• Avoid walking barefoot in communal showers/pools.

Prognosis

• Treatment requires patience: Toenails may take 12–18 months for full regrowth.
• Recurrence is possible without preventive measures.