Types of Staph Infections
Staph infections frequently result in minor skin problems that can be treated at home. S. aureus is responsible for the majority of skin infections. The most common types of skin infections include:
- Cellulitis is a bacterial infection of the skin and underlying fat tissue.
- Cellulitis usually starts from skin injuries or insect bites, where bacteria enters the skin and spreads into deeper tissues.
- The affected area can feel warm and tender, and appear red and swollen. As the infection spreads, fever, chills, and swollen glands may occur. Medical attention should be sought if these symptoms occur, particularly if the face or groin is involved.
- Individuals who are older, have diabetes or have a weak immune system are more susceptible to this type of skin infection.
- In adults, cellulitis is most prevalent on the lower legs, face, or arms. In children, the face or around the anus are areas most commonly affected.
- The recurrence of cellulitis is possible in those individuals who carry staph bacteria in their nasal passages.
- Serious complications associated with cellulitis include spread of the infection to the blood or lymph nodes, which can be fatal.
- Folliculitis is an infection of the pilosebaceous follicle (unit containing the hair and oil gland) and is possibly the most common form of staph skin infection.
- In folliculitis, a pimple-like whitehead appears at the base of the hair shaft. The infected area is frequently red and swollen.
- Individuals who are staph carriers can experience recurring infections.
- Furuncles (boils) are painful skin abscesses involving the entire hair follicle and surrounding tissue.
- Furuncles occur as a result of the spread of the staph infection deeper into the tissues of the follicles, which results in scarring once the lesions heal.
- S. aureus is the commonest cause of infection; however, other bacteria or fungi found on the skin can also be implicated.
- Furuncles can occur in hair follicles or anywhere on the body, but the most commonly affected sites are the face, neck, armpits, buttocks, and thighs.
- Impetigo is a contagious rash that occurs most commonly in young children.
- Elderly individuals and those with a weakened immune system are also at greater risk.
- Impetigo can result from skin abrasions or insect bites.
- The face (nose and mouth), hands and feet are areas most frequently involved.
- The infected skin appears blistered and lesions can ooze and develop a honey-colored crust.
- The lesions can be itchy, but scratching can spread the infection to other body parts.
- Although the primary infection-causing strain is S. aureus, another type of bacteria (Streptococcus pyogenes) is sometimes the cause.
- A sty (also known as a stye or hordeolum) is an infection that forms at the base of an eyelash or under or inside the eyelid. A sty results from an infection of the oil glands of the eyelid or hair follicle at the base of an eyelash.
- A sty usually appears red and swollen, and causes pain and discomfort of the eyelid.
- It is estimated that S. aureus is responsible for 90-95% of the cases.
If food is stored improperly, staphylococcal bacteria can grow and produce toxins that can cause food poisoning. Symptoms caused by staph-related food poisoning generally are felt within 1-6 hours of ingesting contaminated food. Most people recover quickly within 1-2 days. Symptoms can include abdominal cramps, diarrhoea, nausea and vomiting.
Staph infections can start at the site of a surgical wound or burn following surgery or an injury. Some signs of infection include pus, redness, pain, swelling, warmth and fever. If you suspect your wound is infected, seek medical attention.
Serious Staphylococcal Infections
Serious staph infections rarely develop, however, they can happen when S. aureus enters the bloodstream through breaks in the skin. Individuals with weakened immune systems or chronic illnesses are more susceptible to severe staph infections. Through the release of toxins by the bacteria, staph infections can result in serious or even life-threatening conditions, including:
- Septic shock
- Bone marrow infection (osteomyelitis)
- Infection of the heart valve lining (endocarditis)
- Severe joint problems (septic arthritis)
- Central nervous system – inflammation involving tissues surround the brain and spinal cord (meningitis)
- Infection of the lungs (pneumonia)
- Internal abscesses occurring anywhere in the body
Methicillin-Resistant Staphylococcus aureus (MRSA)
Methicillin-resistant Staphylococcus aureus or MRSA is a type of skin infection that is causing increasing concern in the medical community, due to its rising prevalence. This type of bacteria is commonly referred to as a “superbug” because it has developed resistance to conventional antibiotics, such as methicillin, amoxicillin, penicillin andoxacillin, which are generally used to treat these infections. There is even evidence that some strains of S. aureus have shown resistance to vancomycin, a potent antibiotic that is normally effective against most types of staph bacteria, such cases are referred to as vancomycin resistantStaphylococcus aureus (VRSA).
MRSA occurs most frequently in patients who have undergone medical or surgical procedures, have compromised immune systems, or received medical care in healthcare facilities, such as hospitals or nursing homes. In these healthcare settings, MRSA can cause serious and potentially life-threatening conditions, such as blood-poisoning, surgical site infections, or pneumonia.
Community Acquired-MRSA (CA-MRSA)
More recently, an increasing number of people with MRSA infections have been identified without apparent risk factors, such as recent hospitalization, frequent antibiotic use, a history of intubation, an underlying chronic disorder, catheter use, recent surgical procedure, or close contact with a person who has identified risk factors. Community-associated staph infections are usually seen as skin infections, such as pimples, folliculitis (ingrown hair) and boils, occurring in otherwise healthy individuals.