Protecting Yourself: How to Manage Infections with Type 2 Diabetes

People with type 2 diabetes (T2D) are more prone to infections, which can also become more severe. Elevated blood sugar levels weaken the immune system, making it harder to fight off harmful germs.^1,2

Getting sick can also make blood sugar levels more difficult to control. As your body works to fight an infection, your blood sugar may rise in response. If you notice any signs of infection, talk to your doctor. They can help with treatment and blood sugar management.^1,2

What infections are common for people with T2D?

Knowing what infections are common can lead to early diagnosis and treatment. This can help prevent infections from becoming more serious. It can also reduce long-term complications. The most common infections in people with T2D affect the:^2-4

• Skin
• Soft tissues
• Urinary tract
• Respiratory tract

Foot infections

Foot problems are a common concern for people with T2D, with infections, ulcers, and other complications being major reasons for hospitalization. These issues are often linked to nerve damage (neuropathy), which can make the feet more vulnerable to injury and infection. Neuropathy can lead to:⁵

• Loss of feeling, so you might not notice a foot injury
• Decreased ability to control sweat and oil, which can lead to dry and cracked skin that bacteria can enter
• Foot deformities, which can lead to soft tissue damage

T2D can also reduce blood flow to the feet, making it more difficult for the immune system to fight infections and heal ulcers. Regular foot checks are essential, as cuts or wounds may heal slowly and develop into serious infections. If left untreated, these infections can lead to amputation or, in severe cases, become life-threatening.⁵

Urinary tract infections

T2D raises the risk of urinary tract infections (UTIs) and is a key risk factor for certain rare but severe forms of UTIs. These emphysematous infections, associated with gas formation, can affect the bladder, pelvis, and kidneys.^6,7

Prolonged high blood sugar leads to increased sugar in the urine, creating an environment that supports the growth of gas-producing bacteria. Additionally, people with T2D may have difficulty fully emptying their bladder, allowing harmful bacteria to remain in the urinary tract longer, increasing the risk of infection.⁷

Symptoms of UTIs

Most UTIs develop in the bladder, but if left untreated, they can spread to the kidneys. Kidney infections can complicate T2D management by increasing insulin resistance and making hydration more difficult. Symptoms of a UTI may include:^3,7

• Increased or strong urge to urinate
• Pain or burning feeling when urinating
• Urine that looks cloudy or has blood in it
• Strong-smelling urine
• Nausea or vomiting
• Fever or chills
• Pain in your back, side, or groin

Skin and soft tissue infections

T2D increases the risk of bacterial and fungal infections that affect skin and soft tissue. These infections can affect any skin surface but most often involve the feet.^3,8

Bacterial skin infections

People with T2D may have an increased risk of bacterial skin infections, including:^6,8

• Cellulitis – infection of the skin and underlying tissue
• Necrotizing fasciitis – infection of tissue under the skin that causes death of that tissue (“flesh-eating”)
• Fournier gangrene – a relatively rare form of necrotizing fasciitis affecting the genitals or perineum (area between the anus and genitals)
• Erythrasma – skin infection that most commonly involves toe webs, armpit, and groin areas, causing red-brown patches or plaques
• Folliculitis – infections of the hair follicles
• Styes – infections of the glands of the eyelids at the base of the eyelashes

Fungal infections

The most common fungal infections in people with T2D include:^6,8,9

• Tinea pedis – athlete’s foot
• Onychomycosis – fingernail and toenail infections
• Candidiasis – yeast infections
• Thrush – candidiasis of the mouth and/or throat

Respiratory infections

T2D increases the risk of severe respiratory infections, including pneumonia. People with T2D have higher rates of hospitalization and death from pneumonia.⁶

Symptoms of respiratory infections vary. Possible symptoms include:⁶

• Body aches
• Cough, which may produce discolored or bloody mucus
• Fatigue
• Fever, chills
• Shortness of breath

Ear, nose, and throat infections

Some infections are seen mostly in people with T2D. They tend to be more common when diabetes is uncontrolled. These include:^3,6,10-12

• Malignant (necrotizing) otitis externa – a bacterial infection that starts in the ear and causes severe ear pain and drainage and causes tissue death (“flesh-eating”)
• Rhinocerebral mucormycosis – a fungal infection that starts in the sinuses and can spread to the brain

These are rare but serious infections. They can cause life-threatening complications if not treated quickly.^11,12

Why does T2D cause infections?

Your immune system helps fight off germs. Certain immune cells called white blood cells circulate throughout your body. They trigger your immune system to fight off things that can make you sick (pathogens) like:^1,13

• Bacteria
• Viruses
• Fungi

High blood sugar makes white blood cells work harder. This means your immune system may be weaker. It may have more difficulty fighting off infections. This increases the risk of frequent and severe illnesses. It also makes it harder to recover from illnesses.^1,13

How are infections prevented and treated?

The first step to preventing infections is to keep your blood glucose under control. Other ways to lower your risk of infections include:¹

• Taking medicines as prescribed by your doctor
• Getting enough sleep, exercise, and fruits and vegetables
• Practicing good hygiene by washing your hands often
• Getting a flu shot each year and talking to your doctor about pneumococcal and other vaccines
• Examining your feet and skin every day

Talk to your doctor if you notice any signs of an infection. Treatment varies but often involves antibiotic or antimicrobial drugs. Certain medicines for infection have side effects that may affect T2D management.^6,8