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Gram-Negative Toe Web Infection Differential Diagnoses

  • Author: Robert A Schwartz, MD, MPH; Chief Editor: William D James, MD  more...
Updated: Jun 09, 2016

Diagnostic Considerations

Group A beta-hemolytic streptococci may produce a variety of common childhood cutaneous infections.[6] 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.[7] 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.[8] 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.[9] 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.[10]

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.[11]

In addition, dermatophytids, which result from sensitization to a dermatophyte infection, may be associated with toe web intertrigo.[12]

Interdigital intertrigo and onychomycosis may result in severe bacterial infection with complications including pain, mobility problems, abscess, erysipelas, cellulitis, fasciitis, and osteomyelitis.[13, 14] 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.[15] Another study found a significant association between interdigital tinea pedis and the recurrence rate of erysipelas, but not with erysipelas itself.[16]

The interdigital bacterial infection erythrasma, caused by Corynebacterium minutissimum, should also be considered.[17, 18] Wood-lamp examination is a good idea, but it may not identify all of those infected with this gram-positive rod.

Differential Diagnoses

Contributor Information and Disclosures

Robert A Schwartz, MD, MPH Professor and Head of Dermatology, Professor of Pathology, Pediatrics, Medicine, and Preventive Medicine and Community Health, Rutgers New Jersey Medical School; Visiting Professor, Rutgers University School of Public Affairs and Administration

Robert A Schwartz, MD, MPH is a member of the following medical societies: Alpha Omega Alpha, New York Academy of Medicine, American Academy of Dermatology, American College of Physicians, Sigma Xi

Disclosure: Nothing to disclose.

Specialty Editor Board

David F Butler, MD Section Chief of Dermatology, Central Texas Veterans Healthcare System; Professor of Dermatology, Texas A&M University College of Medicine; Founding Chair, Department of Dermatology, Scott and White Clinic

David F Butler, MD is a member of the following medical societies: American Medical Association, Alpha Omega Alpha, Association of Military Dermatologists, American Academy of Dermatology, American Society for Dermatologic Surgery, American Society for MOHS Surgery, Phi Beta Kappa

Disclosure: Nothing to disclose.

Rosalie Elenitsas, MD Herman Beerman Professor of Dermatology, University of Pennsylvania School of Medicine; Director, Penn Cutaneous Pathology Services, Department of Dermatology, University of Pennsylvania Health System

Rosalie Elenitsas, MD is a member of the following medical societies: American Academy of Dermatology, American Medical Association, American Society of Dermatopathology, Pennsylvania Academy of Dermatology

Disclosure: Received royalty from Lippincott Williams Wilkins for textbook editor.

Chief Editor

William D James, MD Paul R Gross Professor of Dermatology, Vice-Chairman, Residency Program Director, Department of Dermatology, University of Pennsylvania School of Medicine

William D James, MD is a member of the following medical societies: American Academy of Dermatology, Society for Investigative Dermatology

Disclosure: Nothing to disclose.

Additional Contributors

Takeji Nishikawa, MD Emeritus Professor, Department of Dermatology, Keio University School of Medicine; Director, Samoncho Dermatology Clinic; Managing Director, The Waksman Foundation of Japan Inc

Disclosure: Nothing to disclose.


The authors and editors of Medscape Reference gratefully acknowledge the contributions of previous authors, Dr. Frantisek Vosmik, and Jarrett R. Hesselbirg, MD, to the development and writing of this article.

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A 33-year-old man with interweb exudative patches. Courtesy of Rajendra Kapila, MD, Professor of Infectious Diseases, New Jersey Medical School.
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