Understanding the Different Types of Nail Fungus: Causes and Symptoms

Nail fungus, also known as onychomycosis, is a common condition that can cause nails to become discolored, thickened, and brittle. This condition is caused by different types of fungi, each with unique characteristics and symptoms. 

What Are the Different Types of Nail Fungus?

1. Distal Subungual Onychomycosis (DSO)

   • Description: The most common type of nail fungus, distal subungual onychomycosis, affects both toenails and fingernails. This infection starts at the tip of the nail and gradually moves deeper, eventually reaching the nail bed.
   • Symptoms: Early signs include yellow or white spots at the edge of the nail, followed by thickening and discoloration. As the infection progresses, the nail may become brittle, crumbly, and difficult to trim.
   • Cause: DSO is caused by dermatophyte fungi, especially Trichophyton rubrum, which thrive in warm, moist environments. Activities like walking barefoot in public areas such as pools, showers, or gyms can increase the risk of infection.
     
     

2. White Superficial Onychomycosis (WSO)

   • Description: White superficial onychomycosis is a less common type of nail fungus that affects only the surface of the nail rather than the entire nail structure.
   • Symptoms: This type of infection presents as white patches or spots on the surface of the nail, which may spread over time. The nail surface may become rough, soft, and powdery.
   • Cause: WSO is usually caused by the dermatophyte fungus Trichophyton mentagrophytes, which infects the outer layers of the nail.
     
     

3. Proximal Subungual Onychomycosis (PSO)

   • Description: Proximal subungual onychomycosis is a rarer type of nail fungus that starts at the base of the nail near the cuticle and spreads outward.
   • Symptoms: PSO usually begins as a white or yellow spot near the cuticle that expands as the infection progresses. This type of nail fungus can lead to a significant distortion in nail shape.
   • Cause: Often caused by Trichophyton rubrum, PSO may be a sign of a weakened immune system or underlying health conditions like HIV.
     
     

4. Candida Onychomycosis

   • Description: Candida onychomycosis is a yeast infection that affects the nails, usually fingernails. It commonly occurs in individuals whose hands are frequently wet or exposed to moisture.
   • Symptoms: Nails infected with Candida can become discolored (yellow, green, or brown), and they may feel soft or detach from the nail bed. Swelling, pain, and redness around the nail are also common signs.
   • Cause: Caused by Candida albicans and other species of Candida yeast, this infection typically affects people with compromised immune systems or those who work in moist environments.
     
     

5. Endonyx Onychomycosis

   • Description: Endonyx onychomycosis is another rare type of nail fungus where the infection remains inside the nail plate without affecting the nail bed or causing detachment.
   • Symptoms: This type of fungal infection leads to nail discoloration and white streaks across the nail. The nail may become brittle but generally remains attached to the nail bed.
   • Cause: Typically caused by Trichophyton soudanense, endonyx onychomycosis affects the nail’s inner layers, and symptoms are usually milder than in other types.

How to Recognize Nail Fungus Symptoms

Recognizing nail fungus early can improve treatment outcomes. Symptoms may vary depending on the type but generally include:

• Yellow, white, or brown discoloration
• Thickening of the nail
• Brittle or crumbling edges
• Distortion or irregular nail shape
• Separation from the nail bed

If you notice any of these symptoms, especially if they worsen, consulting a healthcare provider is recommended for an accurate diagnosis and to rule out other conditions.