DISCUSSION

Pitted keratolysis (PK) is a relatively frequent superficial bacterial skin infection that typically affects pressure-bearing areas of the soles.^1-5Etiological agents include Corynebacterium spp, Micrococcus sedentarius, Dermatophilus congolensis, Streptomyces, and Actinomyces keratolytica.^3-5These bacteria produce proteases that digest keratin and destroy the stratum corneum, resulting in the characteristic crateriform pitting and erosions.^3,5A malodorous foot odour occurs due to sulfur compounds produced by causal microorganisms, but it is not always present.⁵ Most cases are asymptomatic, although pruritus and a burning or pain sensation may occur on walking.^2-5Predisposing factors include hyperhidrosis, prolonged use of occlusive footwear, humid climate, poor foot hygiene, obesity, diabetes mellitus and immunodeficiency.^2-5Adolescents and young adults are more commonly affected.⁵ There is no racial predilection, but there is a male predominance, presumably due to males’ frequent use of occlusive footwear.^2,5The diagnosis is clinical.^3,5Main differential diagnosis include plantar warts and tinea pedis.^1,3Topical antibiotic therapy, such as clindamycin, erythromycin, mupirocin or fusidic acid, twice daily, usually leads to resolution in 2 to 4 weeks.^3,5Topical benzoyl peroxide is an alternative first-line treatment.⁵ Oral antibiotics are reserved for resistant cases.^4,5Additional measures, such as treatment of concomitant hyperhidrosis and improving foot hygiene, promote clinical resolution and reduce the risk of reinfection.^2,5