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Fungal Nail Infections (Onychomycosis)

Fungal infection of the nails is most common. They crop up in places where heat, humidity and activities require communal bathing.

Seen in approximately 45 per cent of the general population, and in nearly 50 per cent in people over age 70. Nail infections are rare in children.
Did you know that toenails are seven times more likely to be involved than fingernails?

Watch out for these top ten risk factors:

  • Communal bathing
  • Saunas
  • Spas
  • Sporting activities
  • Closed footwear
  • Damaged nails by trauma
  • Conditions changing nails e.g. Psoriasis
  • Genetic susceptibility
  • Diabetes
  • Peripheral vascular disease (damage or dysfunction near the surface of arteries and veins)

What causes nail infections?

  • 50 to 70 per cent are caused by Dermatophytes (T rubrum)a parasitic fungus that affects the skin, hair, or nails
  • 5 to 17 per cent is caused by a fungus called T mentagraphytes
  • Less than 5per cent are caused by parasitic fungi, such as Candida and molds

How do I know if I have a nail infection?

DLSO (Distal and lateral subungual onychomycosis)

  • The nail thickens, starting at the finger tip or the sides of the nail. The nail bed becomes invaded, causing a thickening in the nail that becomes opaque and then turns a creamy or yellow color. Small streaks and patches show up initially but the color of the nail darkens over time.

SWO (Superficial white onychomycosis)

  • On the upper surface of the nail only, there will be chalk-colored patches, caused by a fungus called Trichophyton mentagrophytes.

Distal (furthest part of the nail) onycholysis

  • The nail lifts off the nail bed starting under the tip of the nail.

Proximal (cuticle end) nail fold onycholysis

  • This is when there is separation of all or part of a fingernail or thumbnail from its bed. It is associated with psoriasis or a fungal skin condition, and usually seen in people who are immunodeficient


  • The nail is invaded by the fungus. The skin is not involved at first.
  • This is a rare condition and is seen with scalp/hair shaft endothrix infection, which begins by penetrating the hair.

Chronic paronychia

  • This infection usually starts with the loss of the nail cuticle, which then allows water and yeasts into the tissue, which causes swelling, redness, tenderness and sometimes pus.
  • Seen mostly in middle-aged women from frequent washing of hands in water, handling food, diabetes or steroid use. Usually affects the index, middle finger or thumb.