A diabetic's ankles may swell if there is an infection, a reaction to medication, a blood clot, or heart, kidney or liver failure, explains WebMD. A diabetic may contract a foot infection that makes his ankles swell, because the nerve damage prevents him from feeling his feet, making sores fester.
Swollen ankles are not necessarily indicative of a serious problem for a diabetic, according to the University of Washington Department of Orthopaedic and Sports Medicine. Sometimes it is merely a reaction to medication. However, it needs to be reported to a physician regardless, in case the medication needs to be discontinued or there is a more serious underlying problem.
Swollen ankles can be indicative of more serious problems such as heart or liver failure, issues that a diabetic is more likely to face, according to the University of Washington. Swelling can indicate that protein is getting absorbed in the urine, a sign of kidney disease. It can also mean that the liver is not producing enough of a protein that prevents blood from seeping out of blood vessels, explains WebMD. This blood then collects in the ankles, causing them to swell, which is a sign of liver failure. Swelling ankles can also indicate that the heart is failing.