9 Infections That Cause a Bacterial Skin Rash

Pictures and How to Identify Them

The look of a bacterial skin rash was vary based not only on the type of bacteria involved but also on the location of the rash, the severity of the infection, and, the layer of skin affected. The rash can also look different on different skin tones or on the skin of babies, children, adults, or older adults.

The appearance and location of a rash can provide clues as to which type of bacteria your health provider is dealing with. These include common bacteria like Staphylococcus aureus (often referred to as a staph infection) or Streptococcus pyogenes (also linked to strep throat).

The article describes the symptoms and causes of nine of the most common bacterial skin infections, including how they are diagnosed and treated. It also explains when a rash needs immediate (or even emergency) medical treatment.

Cellulitis

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Cellulitis

Richard Wareham / Getty Images

Cellulitis affects the two deepest layers of the skin called the dermis and subcutaneous tissue. It often appears as a swollen, red area of skin and feels tender and hot when touched.

Cellulitis usually occurs when the skin is broken, such as near ulcers, bruises, burns, or recent surgical wounds. While many types of bacteria can cause cellulitis, Staphylococcus aureus and Streptococcus pyogenes are the most common culprits.

If the cellulitis spreads to your bloodstream, it can be deadly, causing high fever, chills, rapid heart rate, vomiting, and other symptoms of septicemia ("blood poisoning"). Seek emergency care if symptoms like these develop.

Erysipelas

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Erysipelas

 DermNet / CC BY-NC-ND

Erysipelas is an infection of the top two layers of the skin—the dermis and epidermis—by Streptococcus aureus. It is commonly known as "St. Anthony's Fire" because of the intense, burning sensation that it causes.

Symptoms include areas of extreme redness and swelling with a sharply defined border. It is common on the face and legs but can also affect the arms and trunk.

Erysipelas is similar in appearance to cellulitis. However, cellulitis affects the lower layers of the skin.

Minor skin disruptions like athlete's foot or eczema can lead to erysipelas by allowing bacteria into tiny breaks in the skin. It can also occur when bacteria spread to the nasal passages following a nose or throat infection.

Bacterial Folliculitis

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Bacterial Folliculitis

Jodi Jacobson / Getty Images

Bacterial folliculitis is a relatively common infection of the hair follicles. It is usually caused when follicles are blocked by ingrown hairs, oils, or skin care products, trapping bacteria in pores and allowing them to multiply and spread.

Shaving or plucking hairs can increase the risk of bacterial folliculitis by providing bacteria easier access to disrupted pores.

Symptoms include tiny, red bumps and/or white-headed pimples filled with pus. Folliculitis tends to affect people with acne more than those with clearer skin.

While bacterial folliculitis usually heals on its own, severe cases may require topical or oral antibiotics. Left untreated, folliculitis can cause permanent hair loss.

Fungal and Viral Folliculitis

Folliculitis can also be caused by fungi like Pityrosporum or Malassezia or viruses like herpes simplex virus (HSV). It is for this reason that folliculitis should be seen by a healthcare provider to ensure that the right treatment is dispensed.

Hot Tub Folliculitis

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Hot Tub Folliculitis

 Joel Carillet / Getty Images

Hot tub folliculitis is a skin infection by a bacteria called Pseudomonas aeruginosa. Symptoms include pus-filled bumps and an itchy, red rash that can develop several hours or days after exposure to the bacteria. The bacteria can survive even in chlorinated water, making it tougher to kill.

The condition is sometimes called "jacuzzi folliculitis" because it can be contracted through contaminated whirlpools and hot tubs (especially wooden ones). People can also become infected through water slides, physiotherapy pools, or even loofah sponges.

Hot tub folliculitis typically affects the chest or groin. The risk is higher in people with acne or eczema as their skin barrier has already been disrupted.

Hot tub folliculitis tends to resolve on its own but may benefit from topical silver sulfadiazine cream. Severe cases may require oral antibiotics.

Hot Tub Folliculitis in Children

Children are more prone to hot tub folliculitis because their skin is thinner and they tend to stay in the water longer than adults.

Furuncles

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Furuncles

Mahdouch / Wikimedia Commons / CC BY 1.0 

A furuncle, commonly known as a boil, is a painful infection involving a hair follicle. It starts as a red, tender lump that rapidly fills with pus as it gets bigger. If left untreated, a furuncle can become a pus-filled pocket known as an abscess.

Unlike folliculitis, which also involves a hair follicle, a furuncle is an infection of the entire pilosebaceous unit (which includes the follicle, hair shaft, and sebaceous gland).

Furuncles are common on the face, neck, armpits, buttocks, and thighs. Applying warm compresses can help drain pus.

In severe cases, your healthcare provider may need to lance (cut open) the boil to drain it, followed by a course of oral antibiotics.

Carbuncles

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Carbuncles

Drvgaikwad/Wikimedia Commons / CC BY 3.0 

A carbuncle is a cluster of furuncles closely packed together. It can be as large as 4 inches across and usually has one or more openings where pus can ooze out. The infection may also cause a fever, fatigue, and malaise (a general feeling of unwellness).

Carbuncles usually develop on the back, thighs, or back of the neck. The infection tends to be deeper and more severe than that caused by furuncles. The most common cause is Staphylococcus aureus.

Carbuncles are more difficult to treat and can take longer to resolve than boils. The risk of scarring is high as is the spread of infection to other parts of the body. For this reason, carbuncles generally require medical treatment.

Impetigo

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Impetigo

 CFCF / Wikimedia Commons / CC BY 4.0

Impetigo is a bacterial infection of the epidermis. It is highly contagious and more commonly seen in children than adults. Caused by both Streptococcus aureus and Staphylococcus pyogenes, impetigo causes an oozing skin rash covered by a honey-colored crust.

Impetigo usually occurs around the nose and mouth but can spread to other parts of the body through skin-to-skin contact or contaminated clothing or towels. Impetigo is usually treated with topical antibiotics.

Erythrasma

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Erythrasma

 DermNet / CC BY-NC-ND

Erythrasma is a superficial skin infection caused by a bacteria known as Corynebacterium minutissimum. The infection usually starts with a well-defined pink patch of skin covered with fine scales. The rash can then turn a reddish or brownish color with flaking and wrinkling.

Erythrasma develops where skin surfaces rub against each other, such as the armpits, groin, or between the toes. In addition skin discoloration and flaking, mild itching or burning may occur, especially when it occurs in the groin area.

Erythrasma is most common in warm, humid climates. Other risk factors include poor hygiene, obesity, diabetes, and older age.

Topical or oral antibiotics may be used depending on the severity of the rash. Gentle scrubbing can help remove some of the scales.

Erythrasma or Not?

Due to its location and appearance, erythrasma is often confused with fungal infections like athlete's foot or jock itch.

MRSA Infections

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MRSA Skin Infection

CDC / Bruno Coignard, M.D.; Jeff Hageman, M.H.S. / Wikimedia Commons / Public Domain 

Methicillin-resistant Staphylococcus aureus (MRSA) is a serious bacterial infection that is resistant to standard antibiotic treatment.

The symptoms of MRSA can vary by the location of the infection. They typically include redness, swelling, pain, pus, and fever. Some MRSA infections look like other bacterial infections and can even be confused with a spider bite.

Laboratory tests are usually required to diagnose MRSA. If left untreated, MRSA can easily spread from person to person, particularly in hospital settings.

Untreated MRSA

If left untreated, MRSA can spread through the bloodstream, causing septicemia and sepsis (a potentially life-threatening reaction to the blood infection). One in five people hospitalized for sepsis will die as a result of complications.

Summary

A bacterial infection can be caused by any number of different bacteria. Staphylococcus aureus and Streptococcus pyogenes are the two most common.

A bacterial infection can cause localized symptoms (such as with furuncles, carbuncles, erythrasma, and impetigo) or affect larger portions of the body (such as with hot tub folliculitis and erysipelas). Some bacterial infections like MRSA and cellulitis can spread into the bloodstream, causing septicemia and sepsis.

11 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
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By Heather L. Brannon, MD
Heather L. Brannon, MD, is a family practice physician in Mauldin, South Carolina. She has been in practice for over 20 years.