“Usually cellulitis develops when a crack or break in the skin allows bacteria to enter into it,” explains Edidiong C. Kaminska, MD, a Chicago-based dermatologist. It typically affects the dermis — the layer of the skin below the top, outer layer (the epidermis). The dermis contains blood vessels, oil and sweat glands, nerves, hair follicles, and other structures, as well as subcutaneous connective tissue. Occasionally cellulitis spreads to the muscle and bone. (1,2)
What Are the Symptoms of Cellulitis?
“With cellulitis the skin appears swollen and red. It is typically painful and warm to touch,” says Dr. Kaminska. “The most common location for cellulitis is the lower legs, but it can occur on any part of the body, including the face. Additionally, it usually affects one side of the body, so for example, it’s very rare to have cellulitis affect both legs.” It can also affect the area around the eyes (periorbital or preseptal cellulitis) or behind the eyes (orbital cellulitis), she notes. Other symptoms of cellulitis can include:
A skin sore or rash that appears suddenly and worsens quickly within the first 24 hoursA tight, shiny, stretched appearance to the skinJoint stiffness from swelling of the tissue over an affected jointNausea and vomiting
How Is Cellulitis Treated?
“The first line of treatment for cellulitis usually includes a prescription oral antibiotic,” says Kaminska. “Typically you will see a response within the first three days. You should notice that the redness, swelling, and tenderness are starting to go down. It is important for patients to know they should complete the total prescribed course of antibiotic treatment, even if they feel better.” Normally, cellulitis will clear up with antibiotic treatment within 7 to 10 days.
What Are the Complications of Cellulitis?
While cellulitis is usually simple to treat, in rare cases, complications can occur. These can include:
Abscess
“Sometimes the bacteria collect beneath the skin and fill up a pocket with yellow pus, which we call ‘purulent.’ The drainage can be smelly,” says Kaminska. “If cellulitis is complicated by an abscess, the treatment of course is surgery, which involves an incision and drainage. They cut the skin to release that pocket and drain all of the pus out.”
Gangrene
Gangrene is dead or dying tissue, and it happens when the blood supply to the tissue is lost. This can happen for a number of reasons, including infection. The affected site may turn black or blue, discharge pus, hurt, or feel numb. Gangrene caused by or accompanied by infection is a medical emergency, and you should seek help for it immediately. Treatment may include surgery to remove dead tissue, intravenous antibiotics to treat the infection, and hyperbaric oxygen therapy to increase the amount of oxygen in your blood and slow the growth of bacteria that grows best in the absence of oxygen. In extreme cases of gangrene, an amputation may be required. (3,4)
Necrotizing Fasciitis
“Sometimes the infection can go into the deeper layers of the tissue and it can cause necrotizing fasciitis, which is an extreme emergency,” says Kaminska. Also known as “flesh-eating disease,” the condition is caused by a rapidly spreading bacterial infection of the fascia (connective tissue) and surrounding soft tissue, causing the tissue to die and possibly leading to the loss of limbs or even death. The treatment is surgical removal of dead tissue and administration of intravenous antibiotics.
MRSA
In the United States, hospitalizations for cellulitis nearly doubled between 1998 and 2013, to approximately 537,000. The rise in incidents may be partially attributable to a contemporaneous rise in methicillin-resistant Staphylococcus aureus (MRSA) infections, which are resistant to many of the antibiotics used to treat ordinary staph infections. (6,7) Rachel Bystritsky, MD, an infectious disease specialist and assistant professor of medicine at the University of California in San Francisco, says MRSA can be a concern “particularly for cellulitis that involves an abscess or pus or if there are other risk factors like injection drug use.” If the bacteria causing cellulitis is indeed MRSA, she says, “You would need to use drugs that cover MRSA, such as trimethoprim sulfamethoxazole and clindamycin or doxycycline; or if admitted to the hospital, vancomycin is the main drug that we use.”
Orbital Cellulitis
Orbital cellulitis involves the fat and muscle around the eye, affecting the eyelids, eyebrows, and cheeks. “It is an emergency,” says Kaminska. “It can limit eye movement, cause bulging of the eye, pain, and loss of vision.” Discolored eyelids and fever are other symptoms, and left untreated, it can also lead to septicemia (bacteria in the bloodstream, also called bacteremia), cavernous sinus thrombosis (a blood clot in the cavernous sinus, a cavity in the brain), hearing loss, meningitis, and blindness. In children orbital cellulitis can be caused by a sinus infection caused by Haemophilus influenzae, a type of bacteria that causes a variety of types of infections, most commonly in babies and children. (8) Orbital cellulitis should not be confused with the less serious condition of periorbital (or preseptal) cellulitis, Kaminska says. That condition involves the skin around the eye and eyelids, and presents as swelling, redness, and discharge from the eye. “With periorbital cellulitis, the treatment is oral antibiotics, but people with orbital cellulitis need IV antibiotics,” says Kaminska. Surgery may also be needed to drain an abscess or relieve pressure around the eye.
Perianal Streptococcal Cellulitis
Usually occurring in children, this form of cellulitis affects the anus and rectum. The infection can be a result of strep throat, the common cold, or streptococcal skin infection (impetigo). Symptoms include fever, pain, itching, redness around the anus, or blood in bowel movements. Treatments include oral antibiotics such as penicillin and topical antibiotics such as mupirocin (Bactroban). (9) Even in the absence of cellulitis, the perianal skin can be the source for the strep bacteria if a child experiences repeated bouts of strep throat or streptococcal skin infections.
Septicemia
Cellulitis that goes untreated “can go inside of the body, spread to the bloodstream and become life-threatening, though that is very uncommon,” says Kaminska. Septicemia, or infection of the bloodstream, can lead to sepsis, an extreme inflammatory response to infection. Sepsis in turn can lead to septic shock, in which blood pressure drops and the functioning of major organs shuts down. The treatment for septicemia typically requires hospitalization and may include IV antibiotics, medication to raise blood pressure, other medications, oxygen, intravenous fluids, kidney dialysis, and possibly being placed on a breathing machine. (10)
Lymphedema
Lymphedema, or swelling in an arm or leg because of a blockage in the lymphatic system, can be a risk factor for cellulitis, but it can also be caused by cellulitis. Specifically, recurrent cellulitis can damage your lymph drainage system, leading to chronic swelling of the arms and legs. Recurrent cellulitis can be treated with a prophylactic (preventive) course of antibiotics to end the cycle of infections. (11)
How Can You Prevent Cellulitis and Its Complications?
Anything you can do to prevent breaks in your skin will reduce your risk of cellulitis and, hence, complications of cellulitis.
Do What You Can to Avoid Injury
Everyone should take common-sense steps to reduce their risk of skin injury, but if you have diabetes, you may have loss of sensation in your limbs, notes Kaminska, so you may not even notice small wounds. People with diabetes should therefore be extra vigilant about checking their feet, hands, legs, and arms for abrasions, cuts, cracked skin, or injuries. Diabetes may also result in dry, cracked skin, particularly on your feet. (12) This can provide an entry point for bacteria to infect your skin and cause cellulitis. If you have diabetes, make sure you are also going to your podiatrist regularly, Dr. Bystritsky advises.
Treat Any Wounds Immediately
Wash minor wounds with soap and water, apply an antibiotic ointment, and cover the area with a bandage that you change daily (or as often as your doctor recommends). Keep bandages and the injured area clean until it heals. (13) For severe wounds or wounds that aren’t healing normally, see a doctor.
Manage Any Underlying Infections or Diseases That May Have Contributed to Your Cellulitis
Diabetes, cancer, HIV/AIDS, lymphedema, peripheral vascular disease, obesity, and chronic skin conditions such as eczema all raise the risk of developing cellulitis. In the case of recurrent cellulitis, this is especially important to stay on top of, says Bystritsky. “Make sure your skin is in good condition,” she says. “Treat nail fungal infections or fungal infections between the toes.”
Keep Your Skin Clean and Moisturized and Your Nails Well-Manicured
Moisturizing helps keep the skin from cracking and thus providing a way for bacteria to get into the skin. Keeping your nails shorts lessens the likelihood you will scratch yourself.
