Cellulitis: Treatment, types and symptoms


Cellulitis is a bacterial infection in the deeper layers of skin and the fat and soft tissue underneath.

There are around 14.5 million cases of cellulitis each year in the United States.

Some bacteria are naturally present on the skin and do not usually cause harm. However, if they enter the skin, an infection can result. Bacteria can enter through cuts, grazes, or bites.

Cellulitis is not the same as cellulite, a harmless “orange peel” effect that can appear on the upper arms and thighs.

Share on PinterestCellulitis is an infection of the deeper layers of the skin.
Image credit: John Campbell, 2018

Cellulitis is a painful bacterial infection of the deeper layers of skin.

It can start suddenly and become life threatening without prompt treatment.

Mild cases involve a localized infection, with redness in one area. More serious cases involve a rapidly spreading infection that can lead to sepsis.

The spread will depend, to some extent, on how strong the person’s immune system is.

Early treatment with antibiotics is usually successful. Most people receive treatment at home, but some need to receive it in a hospital.

A doctor may suggest one or more of the following treatments:


A mild case of cellulitis usually responds to oral antibiotic treatment in 7–14 days. The symptoms may initially worsen, but they usually start improving within 2 days.

Different types of antibiotics can treat cellulitis. The doctor will decide on the best option, after taking into account the type of bacteria behind the infection and factors specific to each person.

Most people recover within 2 weeks, but it may take longer if the symptoms are severe.

A doctor may prescribe a low-dose oral antibiotic for long term use to prevent reoccurrence.

Treatment in the hospital

Some people with severe cellulitis require hospital treatment, especially if:

  • They have a high fever.
  • They are vomiting
  • They are experiencing a reoccurrence of cellulitis.
  • Current treatment is not working.
  • The symptoms are becoming more severe.

In the hospital, most people with this type of infection receive antibiotic treatment intravenously, with a drip that delivers the medication through a vein in the arm.

There are different types of cellulitis, depending on where the infection occurs.

Some types include:

  • periorbital cellulitis, which develops around the eyes
  • facial cellulitis, which develops around the eyes, nose, and cheeks
  • breast cellulitis
  • perianal cellulitis, which develops around the anal orifice

Cellulitis can occur anywhere on the body, including the hands and feet. Adults tend to develop cellulitis in the lower leg, while children tend to develop it on the face or neck.

Share on PinterestA person with cellulitis may experience infection- symptoms, such as fatigue and cold sweats.

The following symptoms may occur in the affected area:

  • redness and swelling
  • warmth
  • tenderness and pain

Some people develop blisters, skin dimpling, or spots.

A person may also experience other symptoms of an infection, such as:

  • fatigue
  • chills and cold sweats
  • shivering
  • a fever
  • nausea

In addition, the lymph glands may swell and become tender. Cellulitis in the leg, for example, may affect the lymph glands in the groin.

Bacteria from the Streptococcus and Staphylococcus groups are common on the surface of the skin, where they are not harmful.

If they enter the skin, usually through a cut or scratch, they can cause an infection.

Risk factors

Factors that can increase the risk of cellulitis include:

Age: Cellulitis is more ly to occur during or after middle age.

Obesity: Cellulitis is more common among people with excess weight or obesity.

Leg issues: Swelling (edema) and ulceration can increase the risk of developing the infection.

Previous cellulitis: Anyone who has had cellulitis before has an 8–20% chance of it returning, research indicates, and the infection can reoccur several times within a year.

Exposure to environmental factors: These include polluted water and some animals, including fish and reptiles.

Other skin issues: Chicken pox, eczema, athlete’s foot, abscesses, and other skin conditions can increase the risk of bacteria entering the body.

Lymphedema: This can lead to swollen skin, which can crack and allow bacteria to enter.

Other conditions: People with liver or kidney disease have a higher risk of developing cellulitis.

Diabetes: If a person is not able to manage their diabetes effectively, problems with their immune system, circulation, or both can lead to skin ulcers.

Weakened immune system: People may have this if they are older, if they have HIV or AIDS, or if they are undergoing chemotherapy or radiotherapy.

Circulatory problems: People with poor blood circulation have a higher risk of infection spreading to deeper layers of the skin.

Recent surgery or injury: This increases the risk of infection.

Intravenous drug use: Injecting drugs, especially with used needles, can lead to abscesses and infections under the skin, increasing the risk of cellulitis.

A doctor will examine the individual and assess their symptoms.

They may also take a swab or biopsy to find out which type of bacteria is present. Laboratory tests can help rule out other possible causes, as other conditions may look cellulitis.

Identifying the cause and type of bacteria enables a doctor to prescribe the most suitable treatment. However, this can be challenging, as the presence of various types of bacteria on the skin can lead to inaccurate results.

In rare cases, serious complications can arise. They include:

Permanent swelling: Without treatment, the person may develop permanent swelling in the affected area.

Blood infection and sepsis: This life threatening condition results from bacteria entering the bloodstream, and it requires rapid treatment.

Symptoms of sepsis include a fever, a rapid heartbeat, rapid breathing, low blood pressure, dizziness when standing up, reduced urine flow, and skin that is sweaty, pale, and cold.

Infection in other regions: In very rare cases, bacteria that have caused cellulitis spread to infect other parts of the body, including the muscles, bones, or heart valves. If this happens, the person needs immediate treatment.

In most cases, effective treatment can prevent complications.

Cellulitis requires immediate medical treatment — it will not respond to home treatment.

However, a person can do some things to feel more comfortable while waiting for medical attention and during treatment.

Tips include:

  • drinking plenty of water
  • keeping the affected area raised to help reduce swelling and pain
  • moving the affected part of the body regularly to prevent stiffness
  • taking pain relief medication, such as ibuprofen
  • not wearing compression stockings until the infection has healed

Some people try natural remedies that have antibacterial properties, such as thyme and cypress oil. However, there is not enough scientific evidence to show that any plant-based remedies can treat cellulitis.

Anyone with symptoms should receive medical help at once. Untreated cellulitis can be life-threatening.

A person cannot always prevent cellulitis from developing, but there are some ways to reduce the risk.

Treat cuts and grazes: Keep any cut, bite, graze, or wound — including those from recent surgery — clean to reduce the risk of infection.

Avoid scratching: If an insect bite, for example, is itchy, ask a pharmacist about how to reduce this feeling. When scratching is unavoidable, keeping the fingernails clean and short can help prevent infection.

Take care of the skin: Moisturizers can prevent dry skin from cracking, but they will not help if an infection is already present.

Protect the skin: Wear gloves and long sleeves while gardening and avoid wearing shorts if there is a lihood of grazing the skin. Covering up can also help prevent insect bites.

Maintain a healthy weight: Obesity may raise the risk of developing cellulitis.

Avoid smoking and limit alcohol use: These may also increase the risk.

Seek help for other medical conditions: People with diabetes, for example, should do their best to manage their condition.

People who use intravenous drugs can seek help through their doctor or by contacting the U.S. national helpline for treatment referral and information. The number to call is 1-800-662-HELP (4357). Calls are free and confidential and the line is open 24/7.

Cellulitis is a potentially severe infection in the deeper layers of the skin and the tissue beneath.

It can cause severe discomfort, and it can be life threatening. If a person seeks treatment as soon as symptoms appear, there is a good chance that the treatment will be effective.

Having cellulitis once increases the risk of it returning. A person can take some steps to help prevent this.

Source: https://www.medicalnewstoday.com/articles/152663

Cellulitis Treatment, Causes, Symptoms, Pictures & Complications

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Cellulitis usually begins as a small area of pain and redness on the skin. This area spreads to surrounding tissues, resulting in the typical signs of inflammation — redness, swelling, warmth, and pain. A person with cellulitis can also develop fever and/or swollen lymph nodes in the area of the infection.

Learn about cellulitis treatment options » Source: MedicineNet

What is cellulitis?

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Cellulitis is a bacterial infection of the skin and tissues beneath the skin. Un impetigo, which is a very superficial skin infection, cellulitis is a bacterial skin infection that also involves the skin's deeper layers: the dermis and subcutaneous tissue.

The main bacteria responsible for cellulitis are Streptococcus and Staphylococcus (“staph”), the same bacteria that can cause impetigo and other diseases.

MRSA (methicillin-resistant Staph aureus) can also cause cellulitis.

Sometimes, other bacteria (for example, Hemophilus influenzae, Pneumococcus, and Clostridium species) may cause cellulitis as well.

Cellulitis is fairly common and affects people of all races and ages. Men and women appear to be equally affected. Although cellulitis can occur in people of any age, it is most common in middle-aged and elderly people. Cellulitis is not contagious.

Source: MedicineNet

What are cellulitis symptoms and signs?

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Cellulitis has characteristic symptoms and signs. Symptoms usually begins as a small area of tenderness, swelling, and redness that spreads to adjacent skin.

The involved skin may feel warm to the touch.

As this red area begins to enlarge, the affected person may develop a fever, sometimes with chills and sweats, pain, and swollen lymph nodes (“swollen glands”) near the area of infected skin.

What Is a Staph Infection? Symptoms, Pictures See Slideshow Source: iStock

Where does cellulitis occur?

Cellulitis may occur anywhere on the body; the legs are a common location. The lower leg is the most common site of the infection (particularly in the area of the tibia or shinbone and in the foot; see the illustration below), followed by the arm, and then the head and neck areas.

In special circumstances, such as following surgery or trauma wounds, cellulitis can develop in the abdomen or chest areas. People with morbid obesity can also develop cellulitis in the abdominal skin. Special types of cellulitis are sometimes designated by the location of the infection.

Examples include periorbital and orbital cellulitis (around the eye socket), buccal (cheek) cellulitis, facial cellulitis, and perianal cellulitis.

Source: Rafael Lopez

What does cellulitis look ?

The signs of cellulitis include redness, warmth, swelling, tenderness, and pain in the involved tissues. Any skin wound or ulcer that produces these symptoms or signs may be developing cellulitis.

Other forms of noninfectious inflammation may mimic cellulitis. People with poor circulation in the legs, for instance, often develop scaly redness on the shins and ankles; this is called “stasis dermatitis” and is often mistaken for the bacterial infection of cellulitis.

Source: iStock, Medscape

What are cellulitis risk factors?

Most commonly, cellulitis develops in the area of a break in the skin, such as a cut, small puncture wound, or insect bite. In some cases when cellulitis develops without an apparent skin injury, it may be due to microscopic cracks in the skin that are inflamed or irritated. It may also appear in the skin near ulcers or surgical wounds.

In other circumstances, cellulitis occurs where there has been no skin break at all, such as with chronic leg swelling (edema).

A preexisting skin infection, such as athlete's foot (tinea pedis) or impetigo can be a risk factor for the development of cellulitis.

wise, inflammatory medical conditions or diseases of the skin such as eczema, psoriasis, or skin damage caused by radiation therapy can lead to cellulitis.

People who have diabetes or diseases that compromise the function of the immune system (for example, HIV/AIDS or those receiving chemotherapy or drugs that suppress the immune system) are particularly prone to developing cellulitis.

Conditions or diseases that reduce the circulation of blood in the veins or that reduce circulation of the lymphatic fluid (such as venous insufficiency, obesity, pregnancy, or surgeries) also increase the risk of developing cellulitis.

Cellulitis See pictures of Bacterial Skin Conditions See Images Source: CDC – Janice Carr

What causes cellulitis? Is cellulitis contagious?

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The majority of cellulitis infections are caused by infection with either strep (Streptococcus) or staph (Staphylococcus) bacteria.

The most common bacteria that cause cellulitis are beta-hemolytic streptococci (groups A, B, C, G, and F). A form of rather superficial cellulitis caused by strep is called erysipelas and is characterized by spreading hot, bright red circumscribed area on the skin with a sharp, raised border. Erysipelas is more common in young children.

The so-called “flesh-eating bacteria” are, in fact, also a strain of strep bacteria that can sometimes rapidly destroy deeper tissues underneath the skin. Fasciitis is the term used to refer to inflammation of the very deep lining tissues called fascia. The streptococcal infection known as flesh-eating bacterial infection is an example of fasciitis.

Cellulitis, when untreated, may rarely spread to the deeper tissues and cause serious fasciitis.

Staph (Staphylococcus aureus), including methicillin-resistant strains (MRSA), is another common type of bacteria that causes cellulitis.

There is a growing incidence of community-acquired infections due to methicillin-resistant S.

aureus (MRSA), a particularly dangerous type of staph infection that is resistant to many antibiotics, including methicillin, and is therefore more difficult to treat.

Cellulitis can be caused by many other types of bacteria. In children under 6 years of age, H. flu (Hemophilus influenzae) bacteria can cause cellulitis, especially on the face, arms, and upper torso.

Cellulitis from a dog or cat bite or scratch may be caused by the Pasteurella multocida bacteria, which has a very short incubation period of only four to 24 hours. Aeromonas hydrophilia, Vibrio vulnificus, and other bacteria are causes of cellulitis that develops after exposure to freshwater or seawater.

Pseudomonas aeruginosa is another type of bacteria that can cause cellulitis, typically after a puncture wound.

Cellulitis is not contagious because it is a soft tissue infection of the skin's deeper layers (the dermis and subcutaneous tissue), and the skin's top layer (the epidermis) provides a cover over the infection. In this regard, cellulitis is different from impetigo, in which there is a very superficial skin infection that can be contagious.

What types of health care professionals treat cellulitis?

Primary care specialists, including internists and family medicine specialists, treat cellulitis. For patients who seek medical treatment at an urgent care center or emergency department, emergency medicine specialists may be the treating physicians. Sometimes infectious disease specialists or surgeons may be involved in the medical treatment of cellulitis.

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Source: BigStock

How do health care professionals make a diagnosis of cellulitis? What is the medical treatment for cellulitis?

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First, it is crucial for the doctor to distinguish whether or not the inflammation is due to an infection. The history and physical exam can provide clues in this regard, as can sometimes an elevated white blood cell count.

A culture for bacteria may also be of value in making a diagnosis, but in many cases of cellulitis, the concentration of bacteria may be low and cultures fail to demonstrate the causative organism.

In this situation, cellulitis is commonly treated with antibiotics that are designed to eradicate the most ly bacteria to cause the particular form of cellulitis. If a pus-filled abscess is present, surgical drainage is typically required.

When it is difficult or impossible to distinguish whether or not the symptoms are due to an infection, doctors sometimes treat with antibiotics just to be sure.

If the condition does not respond, it may need to be addressed by different methods dealing with types of inflammation that are not infected.

For example, if the inflammation is thought to be due to an autoimmune disorder, treatment may be with a corticosteroid.

Antibiotics, such as derivatives of penicillin or other types of antibiotics that are effective against the responsible bacteria, are used to treat cellulitis.

If the bacteria turn out to be resistant to the chosen antibiotics, or in patients who are allergic to penicillin, other appropriate antibiotics can be substituted.

Sometimes the treatment requires the administration of intravenous antibiotics in a hospital setting, since oral antibiotics may not always provide sufficient penetration of the inflamed tissues to be effective. In certain cases, intravenous antibiotics can be administered at home or at an infusion center.

The following are some examples of antibiotics that have been used to treat cellulitis:

In all cases, physicians choose a treatment based upon many factors, including the location and extent of the infection, the type of bacteria causing the infection, and the overall health status of the patient.

Source: iStock

Is it possible to prevent cellulitis?

Under some circumstances, cellulitis can be prevented by proper hygiene, treating chronic swelling of tissues (edema), care of wounds or cuts. In other cases, microscopic breaks in the skin may not be apparent and infection may develop.

In general, cellulitis in a healthy person with an intact immune system is preventable by avoiding skin surface wounds. In people with predisposing conditions (see above) and/or weakened immune systems, cellulitis may not always be preventable.

What is the outlook/prognosis for cellulitis? What are complications of cellulitis?

Cellulitis is a treatable condition, but antibiotic treatment is necessary to eradicate the infection and avoid complications and spread of the infection. Most cellulitis can be effectively treated with oral antibiotics at home.

Sometimes hospitalization and intravenous antibiotics are required if oral antibiotics are not effective. Sepsis is a serious complication of cellulitis.

If not properly treated, cellulitis can occasionally spread to the bloodstream and cause a serious bacterial infection of the bloodstream that spreads throughout the body (sepsis).

How long does cellulitis last?

Cellulitis may continue to spread and not resolve until antibiotic treatment is used. Typically, the symptoms disappear three to 10 days after you have begun taking antibiotics.

Medically Reviewed on 7/15/2019


Herchline, Thomas E. “Cellulitis.” Medscape. June 14, 2019. . Spelman, Denis, and Larry M. Baddour. “Cellulitis and skin abscess: Clinical manifestations and diagnosis.” March 28, 2019. .

Stevens, Dennis L., et al. “Practice Guidelines for the Diagnosis and Management of Skin and Soft Tissue Infections: 2014 Update by the Infectious Diseases Society of America.” Clin Infect Dis 59.2 July 15, 2014: e10-e52.

Source: https://www.medicinenet.com/cellulitis/article.htm

Cellulitis: Practice Essentials, Background, Pathophysiology


Certain host factors predispose to severe infection. The elderly and individuals with diabetes mellitus are at risk for more severe disease.

[20] In addition, patients with diabetes, immunodeficiency, cancer, venous stasis, chronic liver disease, peripheral arterial disease, and chronic kidney disease appear to be at higher risk for recurrent infection because of an altered host immune response.

Local control of immune function through interleukin-driven neutrophil recruitment, protective action of antimicrobial peptides, and the integrity of the cutaneous barrier have significant effects on the host’s defense against infection. [21]

Cellulitis due to lymphatic obstruction or venectomy may be caused by non–group A streptococci (ie, groups B, C, and G). [22, 23] Postvenectomy status following saphenous vein stripping can also result in cellulitis.

[22] Lymphadenectomy following tumor excision, such as mastectomy, is also a predisposing factor for cellulitis.

Immunogenetic factors may play a role in some families who have an underlying susceptibility to an infection progressing to cellulitis.

Other factors that affect host immunity and predispose to cellulitis include concurrent intravenous or subcutaneous “skin popping” drug use; infections in this setting may be polymicrobial, but community-acquired methicillin-resistant S aureus (CA-MRSA) is the most common pathogen in these patients (see the following images).

Patient with cellulitis of the left ankle. This cellulitis was caused by community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA). (Photo courtesy of Texas Dept. of Public Health.) Abscess and associated cellulitis caused by community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA). (Photo courtesy of Texas Dept. of Public Health.)

In individuals with normal host defenses, the most common causative organisms are group A streptococci (GAS) and S aureus.

Group B Streptococcus cellulitis occurs in infants younger than 6 months, because their immune responses are not fully developed, and it may also be seen in adults with comorbidities such as diabetes or liver disease. For infantile cellulitis, presentations may include sepsis. [24]

Historically, facial cellulitis in children was frequently associated with H influenzae type B and S pneumoniae, but this is now generally considered a rarity because of routine H influenza e type B and pneumococcal vaccines.

However, a study of 500,000 pediatric hospitalizations demonstrated that, although bacterial meningitis and epiglottitis diminished as a result of immunization for H influenzae type B and S pneumoniae, the incidence of facial cellulitis was unaffected.

[25] Nonetheless, another study noted that 96% of the serotypes that cause facial cellulitis were included in the heptavalent-conjugated pneumococcal vaccine that was routinely used at the time of the study.

Impetigo is commonly caused by strains of S aureus and/or S pyogenes, and erysipelas (acute infection of the upper dermis, characterized by a sharply demarcated, raised border) is more commonly caused by streptococcal species such as S pyogenes.

Immunocompromised hosts may become infected from nontraditional cellulitis organisms, including gram-negative rods (eg, Pseudomonas, Proteus, Serratia, Enterobacter, Citrobacter), anaerobes, and others (eg, Helicobacter cinaedi, Fusarium species). Although fungi (eg, Cryptococcus) and herpes simplex virus may also cause cellulitis, these causes are rare.

Pneumococci may cause a particularly malignant form of cellulitis that is frequently associated with tissue necrosis, suppuration, and bloodstream invasion.

Two distinct syndromes are recognized: the first is marked by involvement of the extremities in patients with diabetes or substance abuse, and the second is marked by involvement of the head, neck, and upper torso in patients with systemic lupus erythematosus, nephrotic syndrome, or hematologic disorders. [26]

Mycobacterial infections may present as cellulitis.

In contradistinction to the usual bacterial cellulitis, these presentations often range from subacute to chronic and are typically unresponsive to short courses of antibiotics—which should then prompt further investigation.

The diagnosis is made on the basis of the presence of granulomas, multinucleated giant cells, and acid-fast bacilli (A) from biopsy specimens or mycobacterial culture. [27, 28, 29]

S aureus is the leading cause of soft-tissue infections in injection drug users, [30] followed by Streptococcus species. [31]

Gram-negative bacteria may cause bullous cellulitis in patients with cirrhosis. [32] Early recognition is vital, because the course of the disease is rapid, typically progressing to septic shock and death. Gram stain and culture of fluid aspirated from the bullae may aid in management.

Recurrent staphylococcal cellulitis may occur in otherwise immunologically normal patients with nasal carriage of staphylococci and those with Job syndrome.

Various hospital-acquired infections following soft-tissue trauma may lead to cellulitis.

It is unusual to have infection occur in areas around surgical wounds less than 24 hours postoperatively, but if there is such a clinical problem, group A beta-hemolytic Streptococcus [GABHS] or Clostridium perfringens (which produces gas that may be appreciated as crepitus on examination) is the usually cause. Acinetobacter baumannii is an emerging multidrug-resistant pathogen in these scenarios. [33]

Cellulitis due to lymphatic obstruction or venectomy may be caused by non–group A streptococci (ie, groups B, C, and G). [22, 23] Postvenectomy status following saphenous vein stripping can also result in cellulitis.

[22] Cellulitis may also be associated with tinea pedis, and in such cases, culture of toe-web spaces may help identify a bacterial pathogen.

[34] Lymphadenectomy following tumor excision, such as mastectomy, is also a predisposing factor for cellulitis.

Cellulitis can complicate varicella and may be identified by larger margins of erythema surrounding the vesicles. One study identified patients with invasive GAS cellulitis complicating varicella.

[35] The median onset of GAS infection was day 4 of varicella, with fever, vomiting, and localized swelling reported. This condition mandates antibiotic treatment and careful clinical follow-up.

Untreated cellulitis in association with varicella may progress to severe necrotizing soft-tissue infections requiring surgical intervention. [36]

Although cellulitis can be complicated by abscess formation, it typically develops from an abscessogenic focus. One maxim in microbiology is the following: “The hallmark of staph infection is abscess formation.” This has become a significant concern because of changing patterns of antibiotic resistance of S aureus, particularly MRSA. [37]

MRSA was first reported in 1968 [38] ; for years, MRSA infections were identified only in patients with recent hospitalization, surgery, renal dialysis, residence in long-term-care facilities, or IV drug use.

However, in the 1990s, isolates of S aureus were found in patients without risk factors for nosocomial disease.

[39] These isolates, which mostly maintain susceptibility to antibiotics such as trimethoprim-sulfamethoxazole or tetracycline, have been termed CA-MRSA to distinguish them from the previously identified hospital or health-care-associated MRSA (HA-MRSA). (See the images below.)

Patient with cellulitis of the left ankle. This cellulitis was caused by community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA). (Photo courtesy of Texas Dept. of Public Health.) Abscess and associated cellulitis caused by community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA). (Photo courtesy of Texas Dept. of Public Health.)

Although reports have indicated that MRSA causes the majority of skin and soft-tissue infections (SSTIs), these studies are plagued by variability in case-finding methodologies.

[40] Furthermore, in the context of cellulitis, the finding is misleading in that these reports come from analysis of wound cultures in cases in which abscess formation occurred. Cultures in cellulitis are difficult to perform and frequently do not yield positive results; therefore, these tests are rarely done clinically.

Consequently, the results of these studies cannot be generalized to cellulitis without abscess formation. Studies are under way to determine the incidence of S aureus —in particular, CA-MRSA in soft-tissue infection in which there is no identifiable abscess.

However, until results of those studies are available, treatment decisions must be made on clinical grounds. Because treatment failures after empiric treatment may often occur, because of the emergence of resistantstrains,microbiologicinvestigations are strongly recommended.

Mammalian bite wounds represent a specific subset of cellulitis with unique pathogens. The infections are usually polymicrobial.

[41] Human, dog, cat, and wild-animal bites all predispose to cellulitis with unique pathogens, but dog bites are the most commonly encountered bite wound in both the primary care and the emergency setting.

[42] Several organisms are of particular interest in animal bites, including the following [41] :

  • Capnocytophaga canimorsus (dog)
  • Eikenella corrodens (human)
  • Pasteurella multocida (dog or cat)
  • Streptobacillus moniliformis (rat)

Puncture wounds, especially through the bottom of athletic shoes, may cause Pseudomonas osteomyelitis and/or cellulitis.

However, lacerations and puncture wounds sustained in an aquatic environment (eg, oceans, lakes, streams) may be contaminated with bacteria not typically found in land-based injuries, including Aeromonas hydrophila, Pseudomonas and Plesiomonas species, Vibrio species, Erysipelothrix rhusiopathiae, and Mycobacterium marinum. [43] Individuals with chronic liver disease are particularly susceptible to V vulnificus infections (see the image below). [44]

Cellulitis due to documented Vibrio vulnificus infection. (Image courtesy of Kepler Davis.)

Source: https://emedicine.medscape.com/article/214222-overview

Cellulitis: Symptoms, Causes, Treatments


Cellulitis is a common infection of the skin and the soft tissues underneath. It happens when bacteria enter a break in the skin and spread. The result is infection, which may cause swelling, redness, pain, or warmth.

You’re at risk if you have:

  • Trauma to the skin
  • Diabetes
  • Circulatory problems, such as not enough blood flow to your arms and legs, poor drainage of your veins or lymphatic system, or varicose veins — twisted, enlarged veins near the surface of the skin
  • Liver disease such as chronic hepatitis or cirrhosis
  • Skin disorders such as eczema, psoriasis, or infectious diseases that cause sores, such as chickenpox
  • Injuries that tear the skin
  • Infections after surgery
  • Long-term skin conditions such as eczema or psoriasis
  • Foreign objects in the skin
  • Bone infections underneath the skin. (An example is a long-standing, open wound that is deep enough to expose the bone to bacteria.)

Cellulitis can appear on almost any part of the body. It usually shows up on damaged skin such as inflamed wounds, dirty cuts, and areas with poor circulation. It needs to be treated by a doctor. Common symptoms include:

  • Redness
  • Red streaking
  • Swelling
  • Warmth
  • Pain or tenderness
  • Leaking of yellow, clear fluid or pus

Go to the emergency room if you have any of the following:

  • High fever or chills
  • Nausea and vomiting
  • Enlarging or hardening of the reddened area
  • Increased pain
  • Numbness of the area when touched
  • Other medical problems that may be affected by even a minor infection

Your doctor will do a medical history and physical exam. Additional procedures include:

  • A blood test if the infection is suspected to have spread to your blood
  • An X-ray if there’s a foreign object in the skin or the bone underneath is possibly infected
  • A culture. Your doctor will use a needle to draw fluid from the affected area and send it to the lab.
  • Rest the area.
  • Elevate the area to help reduce swelling and relieve discomfort.
  • Use over-the-counter pain relievers such as acetaminophen (Tylenol) or ibuprofen (Motrin) to ease the pain, as well as keep your fever down.

If the infection isn’t too bad, you can take antibiotics by mouth for a week to 14 days. Your doctor will schedule a follow-up appointment. Your doctor may use IV or intramuscular antibiotics if:

  • The infection is severe.
  • You have other medical problems.
  • You are very young or very old.
  • The cellulitis covers large areas, is on your hands, or is close to body parts your eyes.
  • The infection worsens even after taking antibiotics for 2 to 3 days.

In serious cases, you may need to stay in the hospital. You’ll get IV antibiotics until the infection is under control (2 to 3 days), and then go home with oral medicines.

Rarely, severe cases may need surgery. For example, doctors may need to open and drain an abscess or pus that has collected in the tissue. They may also need to cut away dead tissue to allow healing.

  • Practice good personal hygiene and keep your skin clean.
  • Wear sturdy, well-fitting shoes or slippers with loose-fitting cotton socks. Avoid walking barefoot outdoors.
  • Wash injured skin with soap and water. Make sure it heals over the next few days.

Some injuries are at greater risk for cellulitis than others. Be sure to contact your doctor if you have:

  • Animal or human bites
  • Puncture wounds deeper than a half-inch, such as from stepping on a nail
  • Crushed tissue that bleeds
  • Burns that blister
  • Frostbite
  • Deep injuries with dirt in them
  • Injuries that touch sea water (making them more prone to infection), especially if you have liver disease
  • Diabetes or other significant medical conditions, such as liver or kidney disease
  • Swelling in your arms and legs that does not go away

Most people with cellulitis respond to the antibiotics in 2 to 3 days and begin to improve. In rare cases, the cellulitis may spread through the bloodstream and become serious. Even more rarely, surgery is required to drain an abscess or remove dead tissue.


American Academy of Dermatology.

U.S. National Library of Medicine: “Cellulitis.”

© 2019 WebMD, LLC. All rights reserved. Impetigo

Source: https://www.webmd.com/skin-problems-and-treatments/guide/cellulitis



Cellulitis is a deep infection of the skin caused by bacteria. It usually affects the arms and legs.

It can also develop around the eyes, mouth, and anus, or on the belly. Normal skin can be affected by cellulitis.

But it usually happens after some type of injury causes a skin break, including trauma or surgery. Once the skin breaks, bacteria can enter and cause infection.

Cellulitis is usually caused when bacteria enter a wound or area where there is no skin. The most common bacteria that cause cellulitis include:

  • Group A ß – hemolytic streptococcus (Strep)
  • Streptococcus pneumoniae (Strep)
  • Staphylococcus aureus (Staph)

Staph and strep bacteria are commonly found on the skin and mucous membranes of the mouth and nose in healthy people. The infection happens when there is a break in the skin that lets the bacteria enter. Other causes may include human or animal bites, or injuries that happen in water.

Each person may experience symptoms differently. Common symptoms include:

  • Redness of the skin
  • Swelling of the skin
  • Tenderness
  • Warm skin
  • Pain
  • Bruising
  • Blisters
  • Fever
  • Headache
  • Chills
  • Weakness
  • Red streaks from the original site of the cellulitis

Some cases of cellulitis are an emergency. Always talk with your healthcare provider right away if you notice any of the following symptoms:

  • A very large area of red, inflamed skin
  • Fever
  • If the area affected is causing numbness, tingling, or other changes in a hand, arm, leg, or foot
  • If the skin appears black
  • If the area that is red and swollen is around your eye(s) or behind the ear(s)
  • If you have diabetes or have a weak immune system and get cellulitis

The symptoms of cellulitis may look other skin conditions. Always talk with your healthcare provider for a diagnosis.

Diagnosis is usually a medical history and physical exam. Blood and skin samples may be taken to confirm the diagnosis and the type of bacteria present.

A bacterial culture can sometimes identify the organism causing the condition. This helps guide treatment with the proper antibiotic.

Your healthcare provider will consider your age, overall health and severity of the condition when determining the best treatment for you.

Getting treated right away can help prevent the spread of cellulitis. Treatment may include:

  • Antibiotics (oral, injection, IV, or topical)
  • Keeping the area clean and applying dressings as instructed
  • Surgery
  • If your arm or leg is affected, elevating the arm or leg may help
  • Rest
  • Time to heal 
  • Pain medicine as needed

the physical exam, your healthcare provider may treat you in the hospital, depending on the severity of the cellulitis. In the hospital, you may get antibiotics and fluids through an intravenous (IV) catheter.

In most cases, cellulitis is easily treated with no complications. But in some cases complications of cellulitis can be very serious. These can include extensive tissue damage and tissue death (gangrene). The infection can also spread to the blood, bones, lymph system, heart, or nervous system. These infections can lead to amputation, shock, or even death.

To prevent cellulitis:

  • Use good personal hygiene.
  • Wash hands often.
  • Apply lotion to dry, cracked skin.
  • Use gloves when cuts and scrapes may happen.
  • Wear protective footwear.

If skin breaks happen, keep the area clean and use an over-the-counter antibiotic ointment. Watch for signs of infection. If you have diabetes, visually check your feet for signs of skin breaks or infection. Also, don’t cut out warts or calluses, and don’t cut toenails too short.

If a wound starts to swell, turn red, feel warm, become painful, or the redness/warmth starts to spread from the wound, see your healthcare professional right away.

Key points about cellulitis

  • Cellulitis is a deep bacterial infection of the skin.
  • Cellulitis usually causes redness, swelling, and tenderness.
  • Good hygiene and skin care can help prevent cellulitis.
  • Watch any breaks in the skin for signs of infection.
  • Untreated cellulitis can lead to amputation, shock, and even death.

Tips to help you get the most from a visit to your healthcare provider:

  • Know the reason for your visit and what you want to happen.
  • Before your visit, write down questions you want answered.
  • Bring someone with you to help you ask questions and remember what your provider tells you.
  • At the visit, write down the name of a new diagnosis, and any new medicines, treatments, or tests. Also write down any new instructions your provider gives you.
  • Know why a new medicine or treatment is prescribed, and how it will help you. Also know what the side effects are.
  • Ask if your condition can be treated in other ways.
  • Know why a test or procedure is recommended and what the results could mean.
  • Know what to expect if you do not take the medicine or have the test or procedure.
  • If you have a follow-up appointment, write down the date, time, and purpose for that visit.
  • Know how you can contact your provider if you have questions.

Source: https://www.cedars-sinai.org/health-library/diseases-and-conditions/c/cellulitis.html