Cellulitis (Skin Infection): Causes, Symptoms, and Treatments

There are a range of symptoms here, varying from mild to severe. These include:

• Redness of the skin - the skin becomes noticeably red and inflamed, often with well-defined edges.

• Warmth - the skin feels warm to the touch as blood flow increases to the infected area.

• Swelling - the area swells due to the accumulation of fluid and inflammatory cells.

• Tenderness or pain in an area of skin

• discharge - such as leaking yellow clear fluid or pus.

• Pain - the infected area is typically tender and painful, with discomfort worsening over time.

• Fever - high temperature often accompanies the infection as the body responds to the bacteria.

The infection can sometimes spread to the rest of the body, and in this case, the lymph nodes may swell and be noticed as a tender lump in the groin and armpit. You may also have fevers, sweats and vomiting.

Types of Skin Infections

Cellulitis is one type of skin infection. Other skin infections include impetigo, caused by the same bacteria, and fungal infections. While cellulitis is a bacterial infection, understanding its place among various skin infections helps in diagnosing and treating it effectively.

Bacterial Infection

Cellulitis is primarily caused by bacteria such as Streptococcus and Staphylococcus. These bacteria can enter the skin through breaks, cuts, or insect bites. Once inside, they multiply and cause infection, leading to the symptoms of cellulitis.

The bacteria that cause cellulitis often enter the skin through small injuries. Common entry points include:

• Cuts and scrapes - Minor injuries can become infected if not properly cleaned and treated.

• Insect bites - Bites from insects such as mosquitoes or spiders can introduce bacteria into the skin.

• Other skin breaks - Any break in the skin, including surgical wounds or chronic skin conditions like eczema, cold sores, chickenpox & shingles, can serve as a gateway for bacteria.

Viral skin infections

Distinguishing cellulitis from viral skin infections is crucial for appropriate prevention and treatment. Unlike bacterial cellulitis, viral skin infections like herpes simplex or shingles require different management strategies and do not typically benefit from antibiotics. If in doubt, consult a healthcare provider for accurate diagnosis and treatment options.

Infected wound

An infected wound can lead to cellulitis if the bacteria spread beyond the initial site of infection. For example, a minor wound that becomes infected may lead to cellulitis in the surrounding skin.

Risk factors. Several factors increase the risk of developing cellulitis, including:

• Conditions that weaken the immune system, such as diabetes or HIV, make it easier for infections to develop.

• People with chronic health conditions, like diabetes or cardiovascular diseases, are at higher risk.

• Conditions that damage the skin barrier, such as eczema or athlete’s foot, can increase susceptibility to cellulitis.

Is Cellulitis contagious?

Cellulitis itself is not contagious. The bacteria causing cellulitis, such as Streptococcus or Staphylococcus, can be present on the skin or in the environment but require an entry point like a cut or insect bite to cause an infection. Therefore, while the bacteria can spread in some cases (e.g., from a wound to another person’s broken skin), the condition of cellulitis is not spreadable through casual contact or airborne transmission.

The risk of transmitting cellulitis is low compared to other infections like the common cold or flu. Maintaining good hygiene practices is important to prevent bacteria from entering your own or others' skin through cuts or wounds. Proper wound care and hygiene can help minimise the risk of infection spreading from person to person.

To diagnose cellulitis, healthcare providers employ various methods:

Physical examination. The initial step involves a visual and physical examination of the affected area to check for signs of redness, swelling, warmth, and pain.

Imaging tests. In some cases, tests like ultrasound or MRI may be used to assess the depth and extent of the infection, especially if there is concern about complications such as abscesses.

Medical history. A thorough review of the patient's medical history, including recent injuries, skin conditions, or any underlying health issues, helps diagnose cellulitis and understand its possible causes.

Treatment Options for Cellulitis

Antibiotics

Treatment for cellulitis primarily involves antibiotics to combat the bacterial infection. Commonly prescribed antibiotics include:

• For most cases, oral antibiotics like flucloxacillin, cephalexin, or clindamycin effectively treat cellulitis. These medications are typically taken for 7-14 days, depending on the severity of the infection.

• In severe cases or if oral antibiotics are not effective, intravenous (IV) antibiotics such as vancomycin or piperacillin-tazobactam may be required. IV antibiotics are administered in a hospital setting.

Alternative Skin Infection Antibiotics

Besides specific antibiotics for cellulitis, other general antibiotics used for skin infections might also be prescribed, depending on the type of bacteria involved and the patient's response to initial treatment.

Managing cellulitis at home involves several supportive measures:

• Rest: Ensure adequate rest to help the body fight the infection.

• Elevation: Elevate the affected limb, if possible, to reduce swelling and improve circulation.

• Hygiene: Keep the affected area clean and dry. Use gentle soap and water, and avoid scratching or irritating the skin.

Under the Pharmacy First Programme, people can be treated in a pharmacy for infected insect bites if it is safe to do so. There is a strict exclusion & inclusion criteria, so be wary before walking into your pharmacy.

Prevention of Cellulitis

Proper wound care and hygiene are essential in preventing cellulitis. This includes:

• Cleaning wounds: Clean minor cuts, scrapes, and insect bites promptly with soap and water.

• Proper pressing: Use sterile dressings to protect wounds and change them regularly.

Managing underlying health conditions can help reduce the risk of cellulitis. Key measures include:

• Controlling chronic conditions: Keep chronic conditions such as diabetes under control to support a healthy immune system.

• Maintaining immune health: Eat a balanced diet, exercise regularly, and avoid smoking to bolster immune function.

Protecting the skin from injury and infection involves:

• Using protective clothing: Wear appropriate clothing and gear to prevent cuts and abrasions, especially in environments where skin injuries are more likely.

• Treating minor injuries: Address minor skin injuries promptly to prevent them from becoming infected.

Healthwords pharmacists' top tips

Most cases of cellulitis need to be treated with antibiotics but there are other things you can do to help alongside treatment:

• Get plenty of rest. This gives your body a chance to fight the infection.
• Raise the area of the body involved as high as possible. This will ease pain, help drainage and reduce swelling.
• Take pain-relieving medications such as paracetamol or ibuprofen. Please check the label for how much to take and how often. The pain eases once the infection starts getting better.

*Always take the full course of any antibiotics that have been prescribed.

Cellulitis is spread by skin-to-skin contact or by touching infected surfaces so wash your hands regularly, bathe or shower daily and cover the area with a gauze dressing.

To help avoid developing cellulitis in the first place, try to avoid scratching or breaking the skin. If this can't be helped, try to clean any breaks to the skin well to reduce the risk of infection.

If you notice that your symptoms of cellulitis are not improving despite following the prescribed treatment, it's crucial to seek further medical help. Persistent symptoms, such as ongoing redness, swelling, or pain, could indicate that the infection is not responding to the initial antibiotics or that there may be a more serious underlying issue. Persistent symptoms might also suggest that the infection has spread or developed complications.

Immediate medical attention is necessary if cellulitis symptoms become severe or if the infection is spreading rapidly. Severe symptoms include a high fever, chills, extreme pain, or noticeable spreading of the redness and swelling beyond the initial site. Rapid spread or severe pain could indicate that the infection is becoming more serious, possibly leading to systemic complications such as sepsis, which requires urgent medical intervention.

Cellulitis in Children

Special considerations are needed when cellulitis occurs in children. Because children’s immune systems and skin are more sensitive, cellulitis can sometimes progress more quickly or cause more significant complications. If a child shows signs of cellulitis, such as redness, swelling, or fever, and especially if symptoms worsen or do not improve with initial care, it is essential to consult a doctor. Children are also more susceptible to complications, so prompt medical attention is crucial for appropriate treatment and management.

What will my doctor do?

Your doctor will ask you about your symptoms, your medical history and any medications you take. They will then examine the area in question and may take your temperature, blood pressure and heart rate readings. The diagnosis of cellulitis is usually made from the clinical presentation alone, and no specific tests are required. If they are, these may include taking a swab from the skin and sending it to the laboratory for testing, as well as blood tests and sometimes X-rays or scans.

If cellulitis is suspected, then you will be given a course of antibiotic tablets. If the cellulitis is severe, the doctor may refer you to the hospital for review and possible antibiotic treatment through a drip.