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Medically Reviewed by Elizabeth Gomez MSN, FNP-BC
Skin issues are common in people with diabetes, both type 1 and type 2. Though these problems are often merely “cosmetic,” they can be both uncomfortable and unpleasant to look at. In some cases, damaged skin can lead to infections, always a scary prospect in people with diabetes.
The skin is the largest organ in the body, and its many blood vessels and nerves experience dysfunction when subjected to high blood sugars — just like the rest of the body. Even harmless skin issues are often considered warning signs that hyperglycemia needs to be addressed before it leads to more serious problems.
Diabetes increases the likelihood of a large number of skin conditions. If you’ve noticed curious itching, dryness, or bumps, it’s possible that you’re experiencing a diabetic skin complication.
This article is not intended to help readers diagnose their own skin issues. If you’re experiencing skin problems of any sort, please share your concerns with your doctor.
(This article substantially referenced two sources: the American Academy of Dermatology Association (AAD) and Endotext, an online resource for endocrinologists.)
General Skin Conditions
Dry Skin
Dry skin (xerosis) is more likely in people with diabetes — as many as 40 percent have the condition. Dry skin can be very uncomfortable; the skin may form cracks or scales, especially on the bottom of the feet.
Often, dry skin in people with diabetes is a function of hypohidrosis, a localized loss of the ability to make sweat. Topical treatments like emollients may be able to help. Only good metabolic control can address the root cause, hyperglycemia.
Infections
Diabetes increases the risk of skin infections and also increases the speed with which they grow and spread.
There are two families of skin infections: fungal and bacterial.
Bacterial infections usually present with redness, swelling, pain, tenderness, or warmth at the site of the infection, frequently around the nails, scalp, and eyes.
Fungal infections — including ringworm, jock itch, athlete’s foot, and vaginal yeast infections — may find the body of a patient with diabetes to be especially hospitable, because they can literally feed on the excess sugar. The organisms that cause these infections usually prefer warm, moist parts of the body. These infections are likely to be itchy rashes, characterized by dry scaly skin or blisters.
Treatment: Bacterial infections generally require antibiotics, while fungal infections require targeted antifungal drugs. In either case, good blood sugar control will help reduce the likelihood of infection in the future.
Open Sores
Open sores, cuts, and wounds can happen for any number of reasons, including some of the skin conditions discussed in this article. The important thing to know is that people with diabetes need to take open sores very seriously and get proper treatment as soon as possible. Hyperglycemia dramatically reduces the body’s ability to heal itself and fight off infection. In the worst cases, minor cuts and scrapes have eventually led to amputations. If you have any fear at all that a wound or sore is not healing promptly, please see a doctor as soon as possible.
Diabetic Hand Syndrome
Several other skin complications primarily affect the hands. Various conditions cause the skin of the hands to harden or become waxy; others reduce finger and wrist mobility. If you’re struggling with hand issues, we have an entire article on diabetes hand complications, sometimes referred to by the umbrella term “diabetic hand syndrome”:
Diabetes Hand Complications: Stiff Hand Syndrome, Trigger Finger, and More
Specific Skin Conditions
Acanthosis Nigricans
Key symptom: “Velvety” skin around body creases, particularly the neck, armpits, or groin
Details: Acanthosis nigricans (AN) presents as a band of skin that is darker (from gray to dark brown) and/or thicker. The skin texture is described as “velvety.” Though most common around the neck, armpits, and groin, AN can also affect the elbows, palms, belly button, and the crease below the breast. AN may not itch or otherwise feel different.
AN is a consequence of very high insulin levels and therefore frequently appears before diabetes is diagnosed. In fact, it can alert clinicians to the presence of diabetes or even prediabetes. It is more common in type 2 diabetes and in people with darker skin color and is especially common in Native American teenagers.
Treatment: The best treatment is optimal glycemic control and weight loss. Topical and oral skin medication can help those with painful thickened skin.
Bullosis Diabeticorum
Key symptom: Blisters, large and full of pus, usually on the lower legs and feet
Details: Bullosis diabeticorum, sometimes known as diabetic blisters, is a rare complication that generally occurs in patients with long-standing diabetes, especially those with other complications. It is most common in men over the age of 50.
These blisters can form very rapidly, even overnight, and may be painless. Though the feet and legs are most frequently affected, these blisters can also occur on the hands and arms.
Treatment: Diabetic blisters usually get better in a handful of weeks. However, it’s important to take care that they do not rupture, which can create a risk of infection. Very large blisters may need to be treated by a specialist. Though bullosis diabeticorum is not itself a dangerous condition, it may be treated as a warning sign that patients need to get their blood sugar levels under control.
Diabetic Dermopathy
Key symptom: Shin spots
Details: Diabetic dermopathy is the official diagnosis for minor lesions often seen in patients with diabetes. These lesions most commonly appear on the shins and are sometimes called “shin spots.” They can be found less commonly elsewhere on the body, such as on the sides of the feet or forearms.
Dermopathy lesions may be redder or darker than the surrounding skin color. They may also have a scaly or scar-like surface. They are often round or oval and symmetrical.
Thankfully, lesions usually do not itch, burn, or sting.
Treatment: There is no treatment recommended for diabetic dermopathy. The American Diabetes Association simply states that “dermopathy is harmless and doesn’t need to be treated.” Lesions usually fade after a year or two, but are often replaced by new lesions in other areas, especially if the underlying hyperglycemia is still present.
Eruptive Xanthomatosis
Key symptom: Reddish pimples, generally clustered on the soft side of the elbow and knee
Details: Eruptive xanthomatosis presents as patches of red, rashy pimples. These little papules may be itchy or tender. It is most frequently found in the soft areas opposite joints, such as the crook of the elbow or the back of the knee, though it can also be found on the buttocks and elsewhere on the body.
Eruptive xanthomatosis is rare; it is primarily caused by very high levels of triglycerides. Insulin resistance and insulin deficiency associated with hyperglycemia in diabetes reduce the body’s ability to metabolize triglycerides, making the condition more likely to occur.
Treatment: The only way to treat the root cause of eruptive xanthomatosis is through improved metabolic control, whether by diet, exercise, or medication. Weight loss and improvements in cholesterol or blood sugar control can help resolve the condition.
Granuloma Annulare
Key symptom: Groups of raised bumps that can appear on the trunk or extremities
Details: The papules (bumps) of granuloma annulare will initially be reddish or skin-colored, though they can also appear purple. The bumpy areas may or may not be itchy. These papules can get quite large, up to 5 centimeters across, and the rashes can cover large parts of the body.
Granuloma annulare can resemble the early stages of necrobiosis lipoidica.
A more common form of granuloma annulare, in which the bumps appear in a small ring pattern, is not believed to be associated with diabetes.
Treatment: These bumps may come and go, but the condition can be prolonged and difficult to treat. A 2006 guideline suggests that dermatologists may need to use many different systemic therapies to treat granuloma annulare.
Necrobiosis Lipoidica
Key symptom: Pimples that swell into large, discolored patches on the shins
Details: Not to be confused with the comparatively harmless diabetic dermopathy (see above), necrobiosis lipoidica is a rare condition in which small pimple-like bumps gradually erupt into large patches of swollen, discolored, hardened skin. Though disfiguring, the disease may not have other symptoms.
The early stages of necrobiosis lipoidica can also be confused for granuloma annulare (see above).
Necrobiosis lipoidica usually occurs decades after an initial diagnosis of diabetes and is more common in women than in men. Its cause is somewhat mysterious, as it also occurs in people without diabetes.
Treatment: There’s no known cure for this chronic condition. A minority of cases will resolve spontaneously, and others do not require treatment, especially if the patient does not suffer discomfort. For cases resulting in open sores, clinicians will need to employ wound care. A dermatologist may prescribe steroids or choose from a number of therapies that help with skin ulceration.
Skin Tags
Skin tags — dermatologists call them acrochordons — are harmless, though they are more likely to occur in people with diabetes. In fact, it has been suggested that the appearance of these flaps of skin may indicate diabetes risk in people not yet diagnosed. Skin tags occur most commonly around the neck, eyes, and armpits. They usually don’t require treatment, but if you have skin tags in a particularly unsightly area, it is possible to get them removed.