In older patients with long-standing diabetes, toenails that are thickened and discolored often suggest a fungal infection, according to a presentation at the Council of Nail Disorders in Washington, DC.

Doctors “should be alert to our finding that, in patients at high risk for developing diabetic foot ulcerations, fungal infections of the toenails are common,” Dr. Stephanie Wu, from Rosalind Franklin University of Medicine and Science in North Chicago, told Reuters Health.

Wu also emphasized that just because a nail is thickened and discolored does not mean that there is a fungal infection. These changes may be the result of mild trauma to the foot, such as occurs from wearing ill-fitting shoes.

Wu and colleagues evaluate 96 patients with decreased foot sensitivity, a common finding among diabetics, and thickened, discolored nails. The patients, who were seen for routine care at a diabetes clinic, were all male, an average of 71 years old, and had diabetes for an average 16 years.

The investigators obtained nail clippings of the most affected nail and debris under the nail. Twenty-five of the patients had nail thickening but no evidence of infection. The other 71 patients had fungal nail infections.

Wu noted that antifungal treatment is usually effective, but oral agents must be used with caution because of their association with heart failure and hepatic toxicity.

Successful resolution of the fungal infection is not the only goal of treatment, Dr. Wu noted. Diagnosis of fungal infection of the nail will motivate patients “to pay more attention to their feet, which will ultimately help prevent ulcers from developing.”