Plantar punctate keratolysis is a benign skin condition that affects the soles of the feet, characterized by depressions or perforations in the stratum corneum of the skin. It is usually caused by bacteria, especially species of the genus Corynebacterium, which cause breakdown of skin cells.
Key features:
- Appearance :
- The condition manifests as small depressions or perforations, often surrounded by dry or flaky skin. These lesions may appear as whiteheads or superficial cavities in the skin.
- Location :
- It is mainly found on the plantar surfaces (the soles of the feet), especially in areas of pressure or friction, such as the heels or the soles of the toes.
- Symptoms :
- Spotted keratolysis is usually asymptomatic, but it may be accompanied by itching or mild pain, especially if the lesions are irritated by tight shoes or physical activity.
- Causes :
- It is often associated with factors such as humidity, heat, and the use of closed shoes, which promote bacterial growth. Excessive sweating (hyperhidrosis) can also contribute to the development of this condition.
- Diagnosis :
- Diagnosis is mainly clinical, based on examination of lesions. In some cases, a sample may be taken to identify the presence of the bacteria responsible.
- Treatment :
- Treatment is based on twice-daily local application of topical antibiotics for an average of 3 to 4 weeks: as a 1st line of treatment, erythromycin type Erythrogel® 4% gel for skin application, then clindamycin type Zindacline® 1%, fusidic acid 2% and mupirocin 2%.
- The other part of the treatment consists of strict compliance with hygiene rules :
- Wearing open shoes or shoes with little occlusion adapted to avoid friction responsible for plantar hyperkeratosis;
- The use of cotton socks (avoid synthetics) and wash at 60°C;
- Twice-daily cleaning and drying of the feet (especially in athletes) with antiseptic soap;
- Avoid sharing socks, shoes and towels;
- Regular cleaning of common areas (showers for athletes).
- If excessive sweating is identified as a contributing factor (hyperhidrosis), the application of a 20% aluminium chloride antiperspirant may be useful to reduce it (use 2 to 3 times a week).
- Local injections of botulinum toxin are sometimes performed to reduce hyperhidrosis. This therapy is mainly described for axillary hyperhidrosis.
- Under treatment, the evolution is favorable in 3 to 4 weeks with healing of the lesions and disappearance of the malodorous character.
