Preventing diabetic foot ulcers

Treatment for onychomycosis and toe web bacteria is key, according to Dr. Gary Sibbald (650 words, 2.5 min)

Canadians of African ancestry are twice as likely to be diagnosed with diabetes as compared to white Canadians, according to Statistics Canada. In his presentation at Skin Spectrum Summit in Toronto, Dr. Gary Sibbald spoke about preventing diabetic foot ulcers by outlining treatment for onychomycosis and toe web bacteria. 

“The average wear and tear in the foot for someone who lives an average lifespan is the equivalent of walking 115 thousand miles,” said Dr. Sibbald. 

Many other physical ailments can first manifest in the foot, he said. Those ailments include arthritis, peripheral vascular disease, cardiac disease and diabetes. “A foot out of alignment results in discomfort and pain in the ankle, the knee, the hip, and the back,” he said.

For patients with diabetes, 85 per cent of amputations begin with a foot ulcer, said Dr. Sibbald. For this population, an onychomycosis infection can be especially concerning. 

“In a population of persons with diabetes, one per cent of them have gangrene,” said Dr. Sibbald. For those with diabetes and onychomycosis, five per cent have gangrene, he said. 

He noted that two per cent of persons with diabetes and a foot ulcer will develop gangrene. If they have diabetes, a foot ulcer and onychomycosis, the incidence goes up to six per cent. 

When taking a nail clipping for culture, the most important part is to get the subungual debris, said Dr. Sibbald. 

“This is really where most of the fungus is. About 30 per cent can be falsely negative on culture, so you may need three cultures. But if we see a KOH [test] with fungal filaments, that’s enough,” he said. 

There are 22 different conditions that can mimic fungus, Dr. Sibbald said. He offered a piece of advice for identifying tricky cases. 

“The most important pattern is distal streaking where it’s wider distally than proximally,” he said. 

If unsure about the diagnosis, he recommends 1% hydrocortisone powder and antifungal cream. Dr. Sibbald also talked briefly about bacteria between the toes. The tightest toe web is typically between the fourth and the fifth toe, he said. 

In patients with diabetes, this can become a problem area for bacterial and fungal infections, so he recommends checking in this area first before going proximally to check the others. 

“Bacteria, specifically Staph and Strep, can get in. That causes lymphangitis and subsequent cellulitis, and these people end up in emergency departments,” he said.

The takeaway: He recommends using 10% povidone-iodine on this area by applying it with a cotton applicator. “It’ll control gram-positive, gram-negative and anaerobic bacteria; it will treat dermatophyte fungus, yeast and viruses. This is a way to keep that space clean,” he said. He also recommends breathable footwear for patients with this condition.

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Prevalence of diabetic foot ulcer and associated factors among adult diabetic patients on follow-up clinic at Jimma Medical Center, southwest Ethiopia, 2019: An institutional-based cross-sectional study

  • An Ethiopian study found that the prevalence of diabetic foot ulcers among patients with diabetes mellitus was 11.6 per cent. The study looked at 277 randomly selected patients with diabetes mellitus. Extra attention should be paid to patients with a history of ulceration, according to researchers.

    From “Journal of Diabetes Research”

Association between race/ethnicity and the risk of amputation of lower extremities among medicare beneficiaries with diabetic foot ulcers and diabetic foot infections

  • A U.S. study found that racial disparities exist for patients with diabetic foot ulcers at risk of amputation. The study looked at data from 92,929 Medicare beneficiaries and found that racial disparities were most significant among fee-for-service beneficiaries.

    From “BMJ Open Diabetes Research & Care”

Saving the diabetic foot during the Covid-19 Pandemic: A tale of two cities

  • Due to the Covid-19 pandemic, many outpatient clinics have closed, marking a shift in how diabetic foot ulcers are diagnosed, treated, and cared for long-term, according to a recent study that looked at outcomes in Los Angeles and Manchester, U.K. The authors reported that new models of care for diabetic foot ulcers may be emerging as a result.

    From “Diabetic Care”

VIDEO: Statin Medications May Leave Patients Vulnerable to Skin Infections

  • The study linked the skin infection issues with the discovery that statins may bring on new-onset diabetes.


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Thank you to our panellists and delegates for making Skin Spectrum Summit 2020 a great success. Conference highlights will soon be posted to the Skin Spectrum website. As always, we welcome your questions and comments on topics in Ethnodermatology.

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