NEW YORK (Reuters Health) – The presence of peripheral neuropathy, and not diabetes per se, increases the risk of surgical site infections after foot and ankle surgery, according to findings published in the August 4th online Diabetes Care.

“It is the complications of diabetes, not the diabetes itself,” Dr. Dane K. Wukich from University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania told Reuters Health in an email. “Patients without complications of diabetes (i.e., neuropathy, peripheral artery disease, nephropathy) did not have higher rates of infection than nondiabetic patients.”

Dr. Wukich and colleagues prospectively evaluated the rate of surgical site infections in 1465 consecutive foot and ankle surgical cases.

Surgical site infections developed significantly more often in diabetic patients (21/221, 9.5%) than in nondiabetic patients (30/1241, 2.4%)(P<0.001).

In multivariate logistic regression, however, the only factors independently associated with surgical site infection were neuropathy, current or past smoking, diagnosis of Charcot neuroarthropathy, and increasing duration of surgery.

Diabetes, male sex, and ulcer history were not associated with the development of surgical site infections.

“We actually were not surprised because a previous retrospective study of ours (1000 patients) found similar results,” Dr. Wukich said.

“We recognize that our study group of 221 patients with diabetes is relatively small and that future prospective studies should attempt to have a more equal distribution of patients between the study and control groups,” the authors say.

“We have identified that neuropathy is also associated with noninfectious adverse outcomes in our foot and ankle patients (the bone didn’t heal),” Dr. Wukich said. “Future studies are trying to see if increasing severity of neuropathy, as measured by the Michigan Neuropathy Screening Index, is associated with higher rates of infection.”

“Diabetic patients who avoid the complications of diabetes are less likely to have adverse outcomes after foot and ankle surgery,” Dr. Wukich concluded. “Closely examine these patients before surgery to see if neuropathy is present. It allows you to stratify patients into high risk.”

Reference:
Surgical Site Infections After Foot and Ankle Surgery: A Comparison of Patients With and Without Diabetes
Diabetes Care 4 August 2011.