Hyperkeratotic Rim of Gram-Negative Toe Web Infections

Abstract

T HE LESIONS SHOWN ARE FROM THE PLANTAR surface of a foot of a 41-year-old white man (Figure1) and a foot of a 48-year-old white man (Figure 2). Each photograph represents a case of gram-negative toe web infection that was resistant to several courses of antibiotics, antifungal agents, and immunosuppressants, alone or in combination. With continued disease, development of a hyperkeratotic rim was noted in these 2 cases as well as in other cases seen at our institution. This hyperkeratotic rim pattern seems to be characteristic of toe web infections that are resistant to standard medical intervention. In our experience, surgical debridement of the hyperkeratotic rim and surface exudate with a standard curette with the patient under local anesthesia leads to rapid improvement (Figure 3) with routine wound care and without further medical therapy. The hyperkeratotic rim pattern may be the result of epidermal undermining of the polymicrobial infection and may serve both as a protected environment for the infecting agents and as a barrier to wound healing, blocking lateral epidermal migration. Editor’s Note: The skINsight section is a forum for the presentation of dermatologic images. The current effort is to foster the recognition of patterns in dermatologic disease processes that may enhance both diagnostic and research capabilities. The initial focus is on dermoscopic images. Theoretically, these patterns reflect the interaction of specific gene defects with local environmental factors. The exercise here is to group lesions with similar dermoscopic patterns—not pathologic criteria. The ultimate benign or malignant behavior is not the focus of this section.