What is pitted keratolysis?

Pitted keratolysis is a bacterial skin infection that can affect both the soles of the feet and the palms of the hands. However, it most often affects the feet because of the sweaty environment created by wearing shoes and socks for an extended period of time.

This condition is characterized by small depressions or pits in the top layer of skin and areas of white skin. It can be a cause of smelly feet and is much more common in men than women.

The most common symptom of pitted keratolysis is a noticeable odor from the feet, due to the infection of the skin on the bottom of the feet.

Those with this condition will usually have clusters of “punched-out” pits on the soles of their feet or palms of their hands. The pits will be more noticeable when the skin is wet.

Sometimes these pits can join together, or “coalesce,” to form larger lesions.

There’s also a type of pitted keratolysis where the affected areas of the skin turn red. While the pits themselves usually won’t present with other symptoms, they sometimes feel sore or itch when pressure is put on the foot while walking.

Several different bacterial species will cause pitted keratolysis; the most common culprits are:

  • Corynebacteria
  • Dermatophilus congolensis
  • Kytococcus sedentarius
  • Actinomyces
  • Streptomyces

These bacteria often multiply in wet or moist conditions. This is why people who don’t let their feet air out enough often develop it.

The bacteria on the feet or palms will produce protease enzymes, which destroy the outermost layer of the epidermis, causing the characteristic pitting. The bad smell is caused by sulfur compounds that are produced by the bacteria on the skin.

If you think you have pitted keratolysis, see a doctor. You will need antibiotics to treat the infection.

To diagnose you with pitted keratolysis, your doctor will swab the area or do something called a skin scraping, where your doctor obtains a sample of skin to check for bacteria and parasites under a microscope.

To treat pitted keratolysis, your doctor will most likely prescribe a topical antibiotic or antiseptic, most commonly clindamycin, erythromycin, or mupirocin. It’s also recommended that you avoid tight-fitting socks and shoes. In rare cases, your doctor may suggest a drying agent like Drysol.

In extreme cases, your doctor may recommend shots of botulin to treat this condition.

Pitted keratolysis is both easily treated and preventable. By taking topical antibiotics and other precautions, this condition will usually clear up in about four weeks.

Because this bacterial infection thrives in moist environments, it’s important to keep your feet as dry as possible to prevent pitted keratolysis. Take the following precautions to keep feet healthy and dry:

  • Wear shoes for as little time as possible.
  • Wear socks made of moisture-wicking materials, such as wool and nylon.
  • Wear open-toed sandals as frequently as possible.
  • Wash feet frequently with antiseptic cleanser.
  • Avoid sharing footwear with others.