Gram-Negative Toe Web Infection Differential Diagnoses

Updated: Mar 26, 2021
  • Author: Robert A Schwartz, MD, MPH; Chief Editor: William D James, MD  more...
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DDx

Diagnostic Considerations

Group A beta-hemolytic streptococci may produce a variety of common childhood cutaneous infections. [14] It is typically seen as intense, fiery red erythema and maceration in the intertriginous folds of the neck, axillae, or inguinal spaces, and has a distinctive foul odor. It should also be contemplated in the differential diagnosis of interweb toe infections.

Fungal interdigital tinea pedis should also be considered. [15] Fusarium solani infection may be the nondermatophytic filamentous fungi responsible. Bilateral intertrigo of the third and fourth interdigital spaces of the feet due to a Fusarium solani infection in an immunocompetent Senegalese man has been described. [16] Infection with this mold is potentially dangerous for the immunosuppressed.

Diabetic patients with ischemic foot ulcers differ with neuropathic foot ulcer patients in having a higher frequency of S epidermidis skin colonization and ulcer infection. S epidermidis may be a nosocomial pathogen. [17] The relationship of each other type to interweb infections remains to be determined.

Trichophyton tonsurans tinea gladiatorum is an emerging epidemic among combat-sport athletes, which may involve scalp, trunk, groin, and toe web spaces. [18]

Itchy maceration of the toe webs is a common disorder often confused with tinea. Bacterial cultures often grow mixed pathogens (93%). Pseudomonas aeruginosa, Enterococcus faecalis, and Staphylococcus aureus were the most common pathogens in one study. [19]

In addition, dermatophytids, which result from sensitization to a dermatophyte infection, may be associated with toe web intertrigo. [20]

Interdigital intertrigo and onychomycosis may result in severe bacterial infection with complications including pain, mobility problems, abscess, erysipelas, cellulitis, fasciitis, and osteomyelitis. [21, 22] Dermatophytic infections in interdigital spaces damage the stratum corneum, leading to bacterial proliferation and secondary infection. Although toe web intertrigo temporarily disrupts the skin barrier and is a risk factor for erysipelas, it may not predispose to repeated episodes of erysipelas. [23] Another study found a significant association between interdigital tinea pedis and the recurrence rate of erysipelas, but not with erysipelas itself. [24]

The interdigital bacterial infection erythrasma, caused by Corynebacterium minutissimum, should also be considered. [25, 26] Wood-lamp examination is a good idea, but it may not identify all of those infected with this gram-positive rod.

Differential Diagnoses