Pitted Keratolysis

Definition

• A superficial bacterial infection of the soles, characterised by whitish, malodorous skin with small “punched-out” pits. The condition involves bacterial degradation of the superficial stratum corneum.

Aetiology

• Caused by Corynebacterium, Dermatophilus congolensis, or Kytococcus sedentarius

• Moist environments foster bacterial growth, leading to stratum corneum breakdown.

• Sulfur compounds released by these bacteria cause foul odour.

Risk Factors

• Occupations with prolonged moisture exposure (farmers, athletes, sailors)

• Hot, humid climates, hyperhidrosis, or occlusive footwear

• More common in males

Symptoms

• Whitish, pitted skin on soles, sometimes merging into larger erosions

• Foul odour (often the most prominent clinical feature)

• Can be asymptomatic or mildly uncomfortable

Management

1. Topical Antibiotics

   • Clindamycin 1% lotion applied BD (twice daily) for ~10 days

2. Manage Hyperhidrosis

   • Foot hygiene measures: Frequent sock changes, airing footwear, antiperspirants or foot powders

   • Avoid occlusive shoes or use moisture-wicking socks

3. General Measures

   • Keep feet dry, use antibacterial soaps if needed

   • Consider an antifungal if concurrent tinea pedis is suspected