As people age their ability to fight bacteria decreases and they are more prone to infections of the skin (ulcers) and soft tissue (cellulitis). Most ulcers and cellulitis occur on the feet and legs. The main reasons seniors develop such problems include decreased sensation caused by nerve damage, inadequate blood flow to the lower extremities through clogged arteries, and impaired return of blood from these areas caused by dilated veins. Such veins often cause the legs and feet to swell. Swelling, or edema, impairs the body’s ability to deliver antibiotics and remove bacteria from infected areas.

Several medical conditions, which are more common in seniors, predispose them to skin ulcers and cellulitis. Among these are:

• Diabetes, which causes decreased sensation in the hands, feet, arms and legs as well as increasing arteriosclerosis or narrowing of the arteries

• Arteriosclerosis or poor circulation

• Kidney failure, which may also be a consequence of diabetes or many other conditions, and is more common in older people

• Hypertension, which also causes arterial narrowing

• Lymphedema or generalized swelling of the legs or arms

• Inflammatory diseases, which cause damage to small vessels, such as lupus, vasculitis, rheumatoid arthritis and scleroderma

• High cholesterol, heart disease, sickle cell anemia and inflammatory bowel disease

• Smoking, either current or past

• Cancer or other tumors and treatments for cancer such as chemotherapy that impair the ability to fight infection

• Taking corticosteroids such as prednisone

• Obesity, paralysis, excessive skin moisture and alcohol abuse.

Essential to-do list for diabetes

Diabetics are especially prone to skin ulcers on the legs and feet. They should follow a careful foot care routine, which includes inspecting their feet daily to look for blisters, cracks, sores, redness, tenderness or edema. Daily washing of the feet with warm water and gentle drying are recommended.

Calluses can be treated with a pumice stone. Talcum powder or cornstarch applied to the feet prevents accumulation of moisture, which can make skin breakdown more likely.

Instead of trying to remove calluses or other lesions themselves, patients should see a podiatrist or their health care provider. Toenails need to be trimmed carefully and straight across.

Additional essential measures include clean socks changed daily and comfortable shoes that fit well and don’t crush the toes together or rub any part of the feet. Orthopedic shoes may need to be prescribed.

People who suffer from diabetes will have fewer foot and other problems if they control their blood sugars and stop smoking. A physician should examine any foot injury, sign of infection or skin breakdown; diabetics need to see a podiatrist yearly for a check-up.

Common causes of cellulitis

Any injury that breaks the skin, no matter how small, can lead to cellulitis of the legs or feet. A scratch, scrape, cut or crack in dry skin can allow bacteria to enter the tissue below the surface and cause infection.

Common causes may be insect bites or stings. Scratching these introduces bacteria from the skin surface and underneath the fingernails into the wound where they can grow. Animal and human bites are particularly likely to cause cellulitis that may progress rapidly over a few hours with red streaks or lymphadenitis appearing on the infected extremity.

In addition to the above diabetic foot care recommendations, skin ulcers and infections can be reduced by:

• Managing diabetes, hypertension, elevated cholesterol and triglycerides by taking recommended medications and following dietary changes

• Regular exercise

• Quitting smoking

• Maintaining a healthy weight

• Limiting the amount of salt or sodium in the diet

Ulcers need treatment

A skin ulcer usually appears as a sore that does not heal, or heals and returns.

It may itch, hurt or not cause any abnormal sensation. A rash or brown or discolored skin may surround the ulcer. Any suspected skin ulcer or other signs of infection such as redness, swelling, tenderness, heat or discharge from a wound require a visit to a health care provider who can quickly begin treatment and prevent complications.

Stephanie Jaeger is a retired internist, family practitioner and emergency room physician living in Anchorage.