Cellulitis is a bacterial infection that affects the skin as well as the soft tissues under the surface of the skin. This kind of an infection usually occurs when bacteria enter normal or broken skin and start spreading under the skin into the soft tissues. This causes inflammation and infection in the affected parts of the skin. Cellulitis can either be caused by exogenous bacteria or even by the normal flora of the skin. Cracks in the skin, bruises, cuts, open wounds, surgical wounds, insect bites, burns, and blisters are common sites where such infections develop. Although cellulitis may affect any part of the body, usually the skin on the legs and face are primarily affected by this disease.
When cellulitis was first identified in 1860 it was just considered an inflammatory condition and there was no treatment given. Around 1865 the condition was recognized as a bacterial infection. The type of bacteria that was causing the infection would eventually be identified, which allowed doctors to prescribe the most effective antibiotics. When the infection didn’t respond to commonly prescribed antibiotics, MRSA was suspected and MRSA cellulitis was identified. Currently when diagnosing this bacterial infection, a medical history will be taken.
Cellulitis is a common condition; a general practice with approximately 2000 people will have about 30 consultations for ‘cellulitis and abscess’ each year. Many more people present to emergency departments; in 2003 to 2004, cellulitis or erysipelas accounted for approximately 49,500 hospital admissions in England (0.4%). According to data collected from community hospitals in the US in 2005, cellulitis was the 27th most common primary diagnosis among adults at discharge. A population-based study in the Netherlands found that, in 2001, approximately 28,000 patients presented with cellulitis or erysipelas of the leg. Of these patients, 2200 were hospitalised, with the average cost per hospitalisation of 5346 euros. This accumulated to more than 14 million euros in 2001. Among patients presenting to acute care facilities, men outnumbered women and the lower extremity predominated as the site of involvement. However, some forms of cellulitis are unique to women. Another study of US hospital data showed an increase in visits for skin infection during the emergence of community-associated MRSA; however, further analysis concluded this was mostly due to abscesses rather than cellulitis.
Most commonly, cellulitis affects body parts like the arms, hands, legs, and feet and is therefore known as cellulitis of the extremities. Some of the other types of cellulitis include:
Orbital Cellulitis: This refers to a cellulitis infection inside the socket of the eye and is usually treated as a medical emergency. Some of the factors which increase the chances of orbital cellulitis include eye injuries, infections in the middle ear, teeth, or face, and sinus infections.
Perianal Cellulitis: This is a type of cellulitis infection that affects the anal region. This type of infection is quite common in children and usually more common in boys than in girls. Those suffering from perianal cellulitis usually do not experience symptoms like fatigue, fever, and body aches which are common symptoms in other types of cellulitis. However they may experience other symptoms like painful bowels, bloody stools, anal itching, and tenderness.
Periorbital Cellulitis: This type of cellulitis develops around the eyelids and is more common in children than adults. People suffering from eye injuries, insect bites, and upper respiratory tract infections are more prone to developing periorbital cellulitis. Fever, eyelid redness, redness inside the eye, and inflammation are common symptoms of periorbital cellulitis.
Facial Cellulitis: This facial infection affects people of all ages and may cause serious complications if left untreated. Some of the risk factors which increase the chances of developing this infection include middle ear or tooth infections, upper respiratory tract infections, and lymphatic system problems.
Breast Cellulitis: As the name suggest, this type of cellulitis affects the skin on the breasts. Women suffering from breast cancer and those with a history of lumpectomy are more prone to developing this type of cellulitis.
The following risk factors increase the likelihood of cellulitis.
Leg swelling (edema): This raises the chances of developing cellulitis.
Weakened immune system: Including people who are undergoing chemotherapy or radiotherapy, those with HIV or AIDS, and older adults.
Diabetes: If the diabetes is not properly treated or controlled, a person’s immune system can be weaker, or they may have circulatory problems, which can lead to skin ulcers.
Blood circulation problems: People with circulation issues may develop skin infections.
Other skin infections: Conditions, such as chicken pox and shingles may cause skin blisters. If the blisters break, they can become ideal routes for bacteria to get into the skin.
Lymphedema: This condition causes swollen skin that is more likely to crack. Cracks in the skin may become perfect entry routes for bacteria.
Previous cellulitis: A person who has had cellulitis before has a higher risk than others of developing it again.
Intravenous drug users: Drug addicts who do not have access to a regular supply of clean needles are more likely suffer from infections deep inside the skin.
Cellulitis occurs when bacteria, most commonly streptococcus and staphylococcus, enter through a crack or break in your skin. The incidence of a more serious staphylococcus infection called methicillin-resistant Staphylococcus aureus (MRSA) is increasing.
Although cellulitis can occur anywhere on your body, the most common location is the lower leg. Bacteria is most likely to enter disrupted areas of skin, such as where you’ve had recent surgery, cuts, puncture wounds, an ulcer, athlete’s foot or dermatitis.
Certain types of insect or spider bites also can transmit the bacteria that start the infection. Bacteria can also enter through areas of dry, flaky skin or swollen skin.
Bacteria causes’ cellulitis
Although symptoms may appear in any part of the body, the legs are most commonly affected. The affected area will become:
Some people may develop blisters, skin dimpling, or spots. They might also experience a fever, chills, nausea, and shivering.
Lymph glands may swell and become tender. If the cellulitis has affected the person’s leg, the lymph glands in their groin may also be swollen or tender.
Symptoms of cellulitis
Sometimes cellulitis can spread throughout the body, entering the lymph nodes and bloodstream. In rare cases, it can enter into deeper layers of tissue. Potential complications that can occur are:
A blood infection
A bone infection
An inflammation of your lymph vessels
Tissue death, or gangrene
Diagnosis and test
Your doctor can usually diagnose cellulitis on sight, but they’ll perform a physical exam to determine the extent of your condition. This exam might reveal:
Swelling of the skin
Redness and warmth of the affected area
Depending on the severity of your symptoms, your doctor may want to monitor the affected area for a few days to see if redness or swelling spread. In some cases, your doctor may perform a blood test or a culture of the wound to test for the presence of bacteria.
Treatment and medications
The aim of the treatments for cellulitis is to reduce the intensity of the infection, relieve pain and other cellulitis symptoms, heal the skin, speed up the recovery process, and prevent the infection from reoccurring. Treatment for children suffering from cellulitis depends on their age and the type of cellulitis they are suffering from. In general, some of the common treatments for cellulitis include:
Oral Antibiotics: Doctors usually recommend oral antibiotics to treat this infection, especially is it is restricted to a smaller area. If the infection is widespread or the recovery rate is slow, antibiotics may be injected or used intravenously to combat the infection.
Topical Antibiotics: Mild cases of cellulitis may even be treated with the help of topical antibiotics.
Limb Elevation: In the case of cellulitis of the extremities, doctors recommend elevating the affected limb to reduce the inflammation and swelling.
Hospitalization: This is usually recommended when the cellulitis is severe or causes other complications. Such patients need constant medical attention and it is therefore best for them to be hospitalized.
Although some cases of cellulitis are not preventable, there are things that people can do to reduce their chances of developing it:
Treat cuts and grazes: If the skin is broken because of a cut, bite, or graze, it should be kept clean to reduce risk of infection.
Reduce the likelihood of scratching and infecting the skin: The risk of the skin being damaged by scratching will be greatly reduced if fingernails are kept short and clean.
Take good care of the skin: If the skin is dry, use moisturizers to prevent skin from cracking. Individuals with greasy skin will not need to do this. Moisturizers will not help if the skin is already infected.
Protect the skin: Wear gloves and long sleeves when gardening; do not wear shorts if there is a likelihood of grazing the skin of the legs.
Lose weight if you are obese: Obesity may raise the risk of developing cellulitis.