Medical Services

Fungal Infections

What is a Fungal Infection?

There are two broad categories of fungal infections:

  1. Relatively innocuous fungal infections that live on the skin, hair, and nails (like athlete’s foot or jock itch)
  2. Potentially more dangerous fungal infections that invade deeper structures of the skin or organs in the body called “deep fungal infections”.

Dermatologists treat fungal infections of the skin, as well as fungal infections in hair and nails. Often, these infections appear as itchy, scaley, rashes on the skin. 

Superficial infections are known by common names such as athlete’s foot and ringworm, or by medical names that indicate the fungus (tinea) and location. These infections include: 

  • Tinea unguum (nail)
  • Tinea pedis (foot)
  • Tinea manors (hand)
  • Tinea corporus (body)
  • Tinea cruris (groin)
  • Tinea capitis (scalp)

Nail fungus, known as onychomycosis or tinea unguum, is the most common fungal infection with over 3 million cases a year.

What are the symptoms of a fungal infection?

On the surface, fungal infections on the skin may have no symptoms at all — or they may be itchy, red, and scaly. Infections of the nail may cause the nail to become thickened and uncomfortable. 

Dermatologists can typically diagnose fungal infections immediately by their characteristic appearance. Suspected fungal infections should be confirmed by scrapping a few flakes of skin off the affected areas to examine under a microscope. If it’s a fungal infection, we can often identify the fungal organisms without need of a real biopsy.  

Deeper infections can look like bumps that may be tender or rapidly growing — they generally have a different appearance and often require a biopsy for accurate diagnosis. 

If we suspect a deeper fungal infection, we will biopsy the area. The lab will either try to grow the organism to identify it, or the pathologist will stain the sample to highlight the organism under the microscope. These results can vary showing deep fungal infections, inoculation from a thorn, or other types of injuries.

What causes Fungal Infections? 

Fungal infections are easy to come by. You can pick them up just about anywhere. 

Walking around a locker room or an area that is wet can harbor the fungus and can lead to athlete’s foot or toenail fungus.  Even your own shower can be a source for transmitting the fungus among family members

Some very rare fungal infections are inhaled. These infections typically start in the lungs and migrate to the skin as they worsen. 

What are the treatment options for Fungal Infections?

Infections on your feet or body (like athlete’s foot or ringworm) can be treated with a cream. Since it’s on the surface, you can treat it with a topical anti-fungal medication. 

For fungal infections no longer isolated to a small part of the body (such as ringworm that has spread to the entire body), an oral medication is recommended to fully treat the extent of the infection. 

Toenail fungus infections are best treated with oral medications. Typically, these medications are about 70% effective and require vigilance in preventing recurrence. Toenail fungus usually disappears within six to twelve months of taking the pill and then require regular cream application to keep it from returning. Using these oral medications intermittently or pulse-dosing can be a way to avoid over exposure to these oral medications.

What should you expect during treatment?

Treatment varies based on the exact type of fungal infection. For skin infections, a topical cream can begin to relieve the itch in a few days. 

It will typically take 14 to 28 days to get rid of the fungus, depending on the area of skin that is affected. The thicker the skin the longer that you need to apply the medication. 

It’s important to remember that the anti-fungal medications we have just prevent the fungus from growing, and the skin has to slough off the fungus to get rid of it. (That’s why it’s important to cleanse the shower after each use) Sometimes adding a topical Urea cream can be helpful to turn the skin cell over more quickly.

For nail (or toenail) fungus, patients will notice a gradual cleaning of the nail as the nail grows out over the period of a year. A rim of a normal nail will start to emerge as it grows out from the skin. The new, healthy nail will replace the old, infected nail. However, it’s important to realize that even if you kill the fungus, the nail does not always return to its normal appearance. 

It can take up to six months for a fingernail and up to a year for a toenail to shed the fungus. So, pulse-dosing the oral anti-fungal medication can be helpful to reduce the exposure to the medication.

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