Mayo Clinic: What causes cellulitis, and how is it treated?
Cellulitis is a bacterial infection that typically affects the
deeper layers of your skin and the layer of fat just beneath.
It’s quite common, especially among middle-aged and older
adults. Most often, cellulitis occurs when a crack or cut in
your skin allows bacteria to get inside and multiply.
can range from mild to severe. Most cases are treated
effectively with antibiotics. Prompt treatment is key. If
severe, or when left untreated, cellulitis can spread to your
lymph nodes, bloodstream and deeper tissues, rapidly becoming
usually develops in the lower legs, although it can occur in
any area with skin. The surface skin area appears red and
swollen, and is typically painful and warm to the touch. Over
time, the untreated area of redness expands.
factors can put you at greater risk of cellulitis, including:
Wounds, cuts or incisions
opening in the skin — from a small scratch or an insect bite
to an ulcer or a recent surgery — can provide an entryway
such as athlete’s foot, dermatitis and eczema can cause the
skin to break or crack, and increase your chance of developing
cellulitis. Shingles can cause broken blisters that are
vulnerable to infection. Itching leads to scratching, and
scratching introduces bacteria to deeper layers. Swelling
become swollen because of damage to your veins (edema) or the
lymphatic system (lymphedema) or following surgery. Stretched,
swollen skin can crack, creating an entry point for bacteria.
had cellulitis in the past increases your chances of having it
sensation and an inability to feel an injury can increase the
risk of cellulitis.
conditions such as diabetes or cancer can make you more prone
to infection because of poor circulation or a weakened immune
system. With diabetes, keeping blood sugars in control can
reduce the risk of nerve or blood vessel diseases, as well as
severity of cellulitis.
develop signs or symptoms of cellulitis, see your doctor as
soon as possible. If symptoms are worsening or you also have a
fever or chills, seek emergency care, because the infection
may be severe or spreading rapidly.
a diagnosis, your health care provider likely will review your
medical history and perform an exam to look for skin features
that suggest cellulitis. If signs such as redness and swelling
are developing on both legs, the cause is usually something
other than cellulitis. Sometimes blood tests or imaging are
necessary to rule out other conditions, including a blood clot
in a leg vein (deep-vein thrombosis), a reaction to a drug or
a skin irritant, lymphedema, or an infected joint. For simple,
uncomplicated cellulitis, however, additional testing isn’t
usually improves with antibiotic treatment in combination with
local cares (elevation and compression) that reduce swelling.
Decreased swelling improves blood supply and circulation,
getting the antibiotic to the infection and making the
antibiotic more effective. Also, cool compresses can relieve
antibiotics are taken for five to 14 days, depending on the
severity and location of the infection and response to
treatment. Most people start to feel better within two or
three days of starting treatment; however, it is recommended
that patients complete the entire course of antibiotic
prescribed to ensure the infection resolves and the bacteria
underlying conditions that make you more vulnerable to
cellulitis, such as edema, eczema and diabetes, is also
helpful in clearing up the present infection and preventing a
serious infections may require hospitalization for
administration of antibiotics via IV and close monitoring for
complications and improvement. While complications are rare,
they can be serious and life-threatening. Sometimes, severe
cellulitis can cause the surrounding tissue to die. Rarely,
bacteria can enter the bloodstream, spreading the infection to
distant parts of the body.
have recurring episodes of cellulitis, your doctor may
recommend taking a long-term course of preventive antibiotics
to keep the infection at bay. It also may help to visit with a
dermatologist or an infectious disease specialist to look for
other causes of your symptoms.