Cellulitis
Cellulitis is a bacterial infection affecting the deep layers of the skin and underlying tissues, often caused by streptococcal and staphylococcal bacteria. These bacteria can enter the skin through cuts, insect bites, or sores, posing a risk particularly to individuals with weakened immune systems, older adults, and people with diabetes. Symptoms typically include redness, swelling, warmth, and tenderness in the affected area, as well as possible fever and chills. Diagnosis is usually based on physical observation, though imaging tests may be used in rare cases. Treatment primarily involves antibiotics, monitored closely by a physician, and may require intravenous administration for severe cases. Preventative measures focus on maintaining skin health, treating injuries promptly, and practicing good hygiene. If left untreated, cellulitis can lead to serious complications, such as sepsis or tissue death. Understanding the symptoms, risks, and preventative strategies can help individuals manage their health and reduce the likelihood of developing cellulitis.
Cellulitis
- ANATOMY OR SYSTEM AFFECTED: Skin, tissue
- ALSO KNOWN AS: Bacterial skin infection
Definition
Cellulitis is a bacterial infection of deep skin tissues. Bacteria enter the skin through cuts, insect bites, and sores. People who are susceptible to cellulitis, such as older adults, people with diabetes, or people with weakened immune systems, may develop cellulitis without an obvious break in the skin.
Causes
Streptococcal and staphylococcal bacteria are the most common causes of cellulitis. Methicillin-resistant Staphylococcus aureus(MRSA) infections that lead to cellulitis are often obtained in hospitals. Although bacteria are normally found on the skin, they do not cause problems unless there is a break in the skin.
Risk Factors
The National Institutes of Health estimate that over 14 million cases of cellulitis occur each year in the United States, and it is one of the most common bacterial skin infections. Any exposure to bacteria may lead to cellulitis. People who work in gardens or other outdoor areas without gloves may get bacteria from the soil. Handling poultry, fish, or meat without gloves or careful handwashing also exposes a person to bacteria. Any break in the skin from, for example, surgery, liposuction, eczema, illegal drug use, or athlete’s foot may allow cellulitis to develop. Athletic events, athletic facilities, daycare, and other crowded areas are also sources of infections, including infections with MRSA. Swelling in the legs (edema) from diseases such as peripheral artery disease, even without a break in the skin, may lead to cellulitis. Additional risk factors for cellulitis include having a weakened immune system, circulatory problems, and obesity.
Symptoms
Symptoms of cellulitis include redness, tightness, and a glossy look to the skin. The area may grow in size and be painful, warm, and tender. Fever, chills, and muscle aches may indicate infection. Another symptom is a skin rash that appears suddenly and spreads.
Screening and Diagnosis
There is no screening for cellulitis. A physician usually makes the diagnosis by observing the area of redness. In rare cases, radiology tests such as ultrasound, magnetic resonance imaging, or a computed tomography scan may be used to rule out other problems.
Treatment and Therapy
The primary therapy for cellulitis is antibiotics, drugs prescribed to fight infections. A doctor will carefully monitor the initial response to antibiotics to be sure the infected area improves with treatment. If the cellulitis does not improve, the doctor may take blood samples to determine what bacteria are involved in the infection and to find a more appropriate antibiotic. In rare cases, sepsis (bacteria in the bloodstream) may occur, requiring additional laboratory blood work. Antibiotics may be given by mouth (orally). For cases where the infection is more severe or does not respond to oral antibiotics, intravenous antibiotics (administered directly into the bloodstream using a needle) may be indicated; admission to a hospital is likely, too. Local treatment of the infected area may include elevating the area and applying moist dressings. If not treated, cellulitis can cause more serious problems, including meningitis, infection in the bone, and gangrene (tissue death).
Prevention and Outcomes
Preventing cellulitis means taking care of the skin. Cleanliness; wearing gloves when needed; treating cuts, scrapes, and bites promptly; and treating skin infections such as athlete’s foot immediately are important preventive measures. Persons with risk factors for cellulitis should discuss with their doctor how to prevent its development, including taking antibiotics regularly.
Bibliography
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