Ask the Dermatologists: 

Skin manifestations of diabetes are common and varied.  While anyone can develop skin conditions, people with diabetes may be more prone to developing some of these conditions because high blood sugar levels can weaken the immune system and cause changes in the skin and blood vessels.  Here, we will highlight common skin findings that are more common in people with diabetes.

People with diabetes may develop bacterial or fungal infections more frequently than other people.  Bacterial infections that may commonly occur in people with diabetes include boils or folliculitis (infections of the hair follicle), styes (infection of eyelid oil gland), and infections of the skin around the nails.  The most common cause of fungal infections in people with diabetes is Candida albicans, which usually affects the warm, moist skin folds (armpits, under the breasts, groin, toes) and causes infections like ringworm, jock itch, and athlete’s foot.

People with diabetes can reduce their chances of developing a skin infection by practicing good skin care, which includes using a gentle cleanser when bathing, bathing with warm (not hot) water, and drying the folds of the skin (armpits, under the breasts, groin, toes) carefully to prevent water from staying in these areas or using powders or specialized materials to help keep those areas of the skin dry.  Another aspect of good skin care is checking feet and other easily injured areas daily for minor wounds and treating all cuts and scratches immediately.

People with diabetes can experience itching, which can be caused by dry skin and/or poor circulation.  In addition to keeping diabetes well-managed and practicing good skin care as detailed above, it is important for people with diabetes to moisturize their skin every day.  Dermatologists recommend using a fragrance-free cream or ointment rather than a lotion or a gel, because creams and ointments are more moisturizing for dry skin and fragrances may cause irritations or allergies.

Acanthosis nigricans – People with diabetes or pre-diabetes sometimes notice tan or brown raised areas of skin on the back or sides of the neck, armpits, and other skin folds. This is acanthosis nigricans.  While this skin condition can be inherited or acquired, people with acanthosis nigricans are twice as likely to have type 2 diabetes as those without this skin finding. This condition is harmless, though affected individuals often do not like the cosmetic appearance of it.  There are skin creams to help improve the appearance of the skin. Dermatologists discourage the common behavior of excessively scrubbing these areas because this can thicken the skin and worsen the darkened color.

Eruptive xanthomatosis – This condition is more common in people with diabetes. These are skin-colored or yellowish bumps that appear suddenly, often on the buttocks, arms, or legs. They often are mistaken for pimples and can be tender or itchy. These bumps develop when diabetes is uncontrolled and disappear when diabetes is well-controlled. It is important to tell your doctor if you develop these bumps.

Digital sclerosis – This condition is more common in people with diabetes. People with digital sclerosis develop waxy, tight and thickened skin on the backs of their fingers or toes. Sometimes, if the affected skin overlies a joint, the joints can become stiff. In addition to obtaining better control of diabetes, physical therapy can also help.

Diabetic dermopathy (shin spots) – This is a harmless and asymptomatic skin condition that is common in people with diabetes, occurring in about 50% of people with diabetes. They appear as brown or dull red spots and lines that are slightly depressed into the skin, most commonly on the shin. While these spots sometimes go away on their own, they can persist indefinitely.

Necrobiosis lipoidica – This skin condition often starts as small bumps, which turn into larger areas of swollen and hard skin that has a shiny appearance. The color of the affected areas can be yellow, red, or brown, and the area can be itchy or painful.  While this condition is harmless, it can lead to complications such as erosions or ulcerations, which often follows minor trauma to the affected area. These open areas of the skin can be painful and may become infected or heal with scarring. In rare cases, squamous cell carcinoma can arise due to chronic inflammation in long-standing sites of necrobiosis lipoidica.

For people with diabetes, good skin care is a necessity and not a luxury because it can help prevent life-threatening conditions and also help your skin feel comfortable. If your skin still feels uncomfortable despite good skin care, or if you develop any new changes to your skin, seeking dermatological care can be helpful. Dermatologists frequently treat patients with diabetes who have complications with their skin. If you notice any new bumps or spots on your skin, it is always helpful to take clear, in-focus pictures of these areas of skin to help document a history, but also to show your doctor, especially if the spots change or go away. During your visit, it can be helpful to ask your dermatologist for examples or names of recommended over-the-counter products.

For people with diabetes, it is imperative to seek immediate medical care for any skin or nail infections. Some warning signs include painful or tender skin, skin that looks swollen or red, a wound that starts leaking fluid, or a nail that is starting to lift up. Infections can quickly become serious, especially in people with diabetes.

If your skin condition is persistent or worsens despite better control of your diabetes and good skin care, a dermatologist can help.

The most common type of insulin site skin reactions is related to the injection itself, which includes skin irritation from the solution, itch, pain, bleeding, or bruising. Local site reactions often show up quickly. Other skin complications of subcutaneous insulin injection include lipoatrophy and lipohypertrophy. Lipoatrophy is a selective loss of subcutaneous fat. Lipohypertrophy is a localized growth of subcutaneous fat. Repeated use of the same injection site can irritate the skin and underlying fatty tissue, therefore increasing the risk of developing lipoatrophy or lipohypertrophy. Both of these can impair absorption of insulin.

The integrity of the skin barrier is one of the most common concerns for people with diabetes using insulin pumps and/or continuous glucose monitors (CGM). However, use of continuous glucose monitors has been associated with improved diabetes control when compared to multiple daily injections, so it is important to reduce the burden of skin conditions as much as possible.

Common skin conditions due to insulin pumps include itching, chronic wounds, and skin irritation or nonspecific eczema. These conditions are more common in patients with prior history of eczema. In children, small scars (<3 mm), redness, and lipohypertrophy around the infusion site (described above) are the most common skin conditions.

Common skin conditions due to CGM include irritation and sensitivity to the adhesive, which can often be so distressing that it causes people to stop using their CGM. Additionally, patients can experience discoloration of the skin after having inflammation of the area, known as “post-inflammatory hyperpigmentation.”

In order to prevent chronic wounds and irritation at the areas of infusion/CGM, we recommend use of barrier ointments such as Vaseline to keep the skin protected from the CGM/infusion device. Additionally, it is important to switch bandages immediately when you feel your skin is getting irritated from a bandage. This will help prevent the inflammation from occurring and persisting. If the inflammation still persists, it is important to see a dermatologist to discuss ways to decrease the inflammation, which could include topical steroids.

We also recommend rotating through multiple sites to preserve skin integrity (at least 6-10 sites), as well as allowing prior insertion sites at least 1 week to heal before putting new tapes or adhesives over them. Angled CGMs and infusion sets may allow you more flexibility with placement.

We also recommend minimizing humidity by using an antiperspirant to prevent skin prone to sweating, as well as trimming hair with a dry razor if needed prior to placing the device.

Post-inflammatory hyperpigmentation may fade over time, but if it persists, discuss with a dermatologist the use of creams to help your skin return to your normal skin color.

A good review of dermatologic care for device use in diabetes is below:

Messer LH, Berget C, Beatson C, Polsky S, Forlenza GP:  Preserving Skin Integrity with Chronic Device Use in Diabetes.  Diabetes Technol Ther 2018 Jun; 20 (S2): S254-S264. doi: 10.1089/dia.2018.0080. PMID: 29916740; PMCID: PMC6011799.

Although reusing single-use diabetes supplies may save money, it is important to know that it can increase the risk of skin infection and irritation. In the short term, reusing lancets and syringes can lead to contamination of the skin. Reusing alcohol wipes may lead to use of alcohol wipes which are dry and do not effectively disinfect the skin. In the long-term, this may increase the burden of skin inflammation (potentially leading to discoloration) and may cause ulcers, leading to wounds. In order to decrease these risks, it is important to avoid reusing single-use diabetes supplies when possible (especially lancets, syringes, and other devices that penetrate the skin).

It is important to note that diabetes supplies which touch the skin should not be shared between people with diabetes, particularly lancets and syringes. This is important to prevent infections from bacteria and harmful agents that may travel in the blood.

For people with diabetes, permanent tattoos are generally understood to be safe. Prior to getting the tattoo, it is important to ensure that blood sugars and HbA1c are under good control, in order to support good wound healing. It is critical for everyone, whether or not they have diabetes, to go to a reputable tattoo studio with good hygiene practices – this is important in order to prevent skin infections. Finally, it is important to know that diabetes poses an increased risk of infection and non-healing ulcers – consider getting a tattoo in an area that is less likely to get infected, avoiding areas like the shins, feet, ankles, and common insulin injection sites.

Apart from keeping blood sugar under control, the recommended skincare routines are the same for people with diabetes as they are for people without diabetes. This involves keeping your skin healthy and moisturized, avoiding very hot and frequent baths (to prevent your skin from becoming too dry), and making sure to keep the skin dry in areas of skin folds to avoid irritation and rashes.

We recommend keeping your skin regimen as “bland” as possible – avoid scents and fragrances, and use moisturizers that do not irritate your skin. Use sunscreen with SPF of at least 30 and reapplying multiple times a day when out in the sun in order to provide good sun protection and prevent skin cancers. For areas that are very dry, scaly, or cracking, look for products with an active ingredient of petroleum jelly (aka petrolatum) – this can help lock moisture into your skin, which can be particularly helpful in dry climates.

For people with diabetes, it is important to ensure that you check your body regularly for signs of infection – particularly areas that you may not see often, such as your feet. If you see any blisters, inflammation, drainage, or significant redness, or if you start to feel pain on your skin, it is important to tell your doctor as soon as possible so that they can help evaluate your skin and see if an antibiotic may be needed.

Finally, if you notice anything new, changing, or bothersome on your skin, it is important to see a dermatologist for further evaluation and treatment.