A Helpful Treatment Pearl for Mixed Toe Web Infections
I believe all clinicians would agree that there are few joys greater than seeing a prescribed or recommended treatment, especially for a difficult condition, succeed and ultimately help a patient! By far, the treatment pearl that receives the most positive feedback from patients and colleagues alike is my secret recipe for “foot salad dressing.” No, do not bring this to your next neighborhood barbeque, rather, use it the next time you see a tough-to-treat mixed toe web infection!
Mixed toe web infection can present both diagnostic and therapeutic challenges. The infection can often be mistaken for tinea pedis or eczematous dermatitis. Initially, the infection presents within the interdigital space as mild erythema with scaly, macerated plaques but may progress to edematous, inflamed erosions with a malodorous discharge extending onto the sole or dorsal foot (1). Burning, pain, and pruritus are common symptoms. A well-demarcated edge is a classic physical exam finding (1). Bacterial culture, Wood’s lamp exam, as well potassium hydroxide preparation are useful diagnostic tests to confirm the diagnosis and exclude other etiologies (1).
These interweb infections commonly start as a fungal infection that progresses to a secondary or “mixed” bacterial infection (2). The initial injury to the stratum corneum by dermatophytes sets the stage for bacterial proliferation. This bacterial superinfection is frequently caused by Staph
aureus/epidermidis but Enterococcus faecalis, Klebsiella, and Pseudomonas can be present as well. In fact, Pseudomonas is the most commonly identified organism in gram-negative toe web infections and can be seen alone or within a mixed gram-negative infection (2).
Warm, moist environments present an ideal breeding ground for bacteria and fungi. Therefore, patients will often report a history of damp or sweaty feet as well occupational and/or recreational use of closed-toe or tight-fitting shoes. Smoking and diabetes are also risk factors for the development of a mixed toe web infection (3). Rarely, these infections can lead to cellulitis or
septicemia, especially in our older or immunocompromised patients.
So what to do when you are faced with this challenging condition? Try my recipe for “foot salad dressing!” In my clinical experience, this regimen clears infection quickly and reduces recurrence:
1. Mix 4 tablespoons of salt with 8 tablespoons of white vinegar. White vinegar has been shown to have antimicrobial activity against gram-negative bacteria.
2. Soak multiple cotton balls in the mixture and apply for 5 minutes to the affected area.
3. Rinse with clean water and pat dry
4. Apply a mid-potency topical corticosteroid alongside topical gentamicin
5. Repeat twice daily.
6. I encourage my patients to keep their feet as open to the air as possible and suggest clean cotton between the toes to wick away moisture.
I hope this treatment cocktail proves useful in your day-to-day practice and you are able to put your best “foot’ forward the next time this condition “walks” into your door!
References:
1. Solomon M, et al. Toe web infection: Epidemiology and risk factors in a large cohort study. Dermatology. 2020 Oct;26:1-5
2. Murthy R, Burgin S. Mixed Toe Web Infection in Adult. In: Goldsmith LA, ed. VisualDx. Rochester, NY: VisualDx; 2021.
URL:
https://www.visualdx.com/visualdx/diagnosis/mixed+toe+web+infection?diagnosisId=52771&moduleId=101#:~:text=A%20mixed%20toe%20web%20infection,bacterial%20proliferation%20and%20secondary%20infection. Accessed February 26, 2023.
3. Hay RJ. Gram Negative Toe Web Infection - A Not So Rare but Neglected Syndrome. Acta Derm Venereol. 2019 Oct 30. 99 (12):1070
Eileen Cheever MPAS, PA-C, resides with her husband Aaron in Lunenburg, Massachusetts. She works at Clearview Dermatology in Leominster, Massachusetts. In her spare time, she enjoys cheering on her favorite Boston sports teams and exploring the outdoors with her husband, their daughter Shalane, and their dog, Jasta.