Pitted keratolysis (PK) is a common superficial skin infection primarily affecting the soles of the feet, caused by specific types of bacteria. This condition thrives in warm, moist environments, often leading to discomfort and a noticeable odor. Treatment requires a dual approach targeting the bacterial infection and the underlying moisture issue. This guide details how to identify the condition and outlines the necessary medical and hygiene strategies.
Identifying Pitted Keratolysis
The presence of small, shallow depressions on the soles of the feet is the characteristic visual sign of pitted keratolysis. These “pits” are typically circular and look like they have been punched out of the skin’s surface, often measuring between 0.5 and 7 millimeters in diameter. They tend to cluster on the pressure-bearing areas of the foot, such as the heel and the ball, and become more prominent when the skin is wet or macerated.
The most frequent accompanying symptom is a strong, unpleasant smell emanating from the feet. This foul odor is a metabolic byproduct of the causative bacteria, such as Kytococcus sedentarius or Corynebacterium species, which produce sulfur compounds like thiols and sulfides. The bacteria thrive in the presence of hyperhidrosis (excessive sweating), creating the warm and moist microclimate necessary for the infection to take hold. They release enzymes that degrade the keratin protein in the outermost layer of the skin (stratum corneum), creating the microscopic craters.
Primary Topical Medical Treatments
Since pitted keratolysis is a bacterial infection, treatment primarily involves topical antibiotics prescribed by a healthcare professional. These medications directly eliminate the bacteria responsible for the odor and skin lesions. Commonly used options include topical clindamycin, erythromycin, mupirocin, or fusidic acid in gel or cream formulations.
The typical application regimen involves applying the prescribed antibiotic directly to the affected areas of the soles twice daily. Treatment usually spans two to four weeks, which is sufficient to clear both the visible pits and the accompanying odor. Topical antiseptics can serve as an alternative or supplementary treatment. Benzoyl peroxide gel or cream, for instance, can be applied to the feet, particularly for patients who may not respond to or tolerate a topical antibiotic.
For severe or persistent cases, oral antibiotics like erythromycin or clindamycin may be considered if topical treatments prove insufficient. Effective medical treatment usually leads to the complete resolution of symptoms within three to four weeks. However, the infection can recur if the environmental factors are not addressed.
Essential Foot Hygiene and Moisture Control
Medical treatment alone is often ineffective for long-term management if the underlying issue of excessive moisture is not addressed. The warm, damp environment that allows the bacteria to thrive must be eliminated to prevent recurrence. A crucial step involves managing hyperhidrosis using antiperspirants specifically formulated for the feet.
Antiperspirants containing aluminum chloride are recommended because they physically reduce sweat production, creating a less hospitable environment for the bacteria. Applying these products regularly to the soles helps keep the feet dry throughout the day. Attention to daily foot hygiene is also necessary.
Feet should be washed at least once daily with soap or an antibacterial cleanser, followed by thorough drying, paying particular attention to the spaces between the toes. Changing socks whenever they become damp is necessary; selecting moisture-wicking materials like synthetic blends or wool is more effective than standard cotton. Rotating footwear is advised to allow shoes to fully dry out for at least 24 hours between uses, as bacteria persist in damp linings. Avoiding occlusive footwear, such as rubber boots or non-breathable vinyl shoes, reduces moisture buildup.