Staph Skin Infections and MRSA

Staph is a shorthand way to talk about the Staphylococcus aureus bacteria, which is a common cause of skin infections.

The symptoms of a staph skin infection depend on where the infection is. The staph bacteria can cause:

• Boils - an abscess within the skin. Also called a furuncle.
• Cellulitis - a localized skin infection which can make the skin red, painful, and warm
• Folliculitis - an infection of hair follicles
• Impetigo - causes blisters (bullous impetigo) or honey-colored crusted lesions on the skin
• Paronychia - an infection of the skin folds of the nails

In addition to skin infections, the staph bacteria can cause:

• Bacteremia - a blood infection
• Deep abscesses - a collection of pus somewhere inside the body
• Endocarditis - an infection of the valves of the heart
• Food poisoning - typically toxin-producing Staphylococcus aureus and raw milk and cheese and other high-risk foods.
• Lymphadenitis - an infection of a lymph gland, which causes it to be red, swollen, and painful
• Lymphangitis - an infection of the lymph channels that drain to lymph glands, causing red streaks in the skin
• Osteomyelitis - a bone infection
• Scalded skin syndrome - can lead to blistering skin that appears scalded and peels away
• Septic arthritis - an infection of a joint, like the hip or knee
• Styes - an infection of the glands on the eyelid
• Toxic shock syndrome - classically associated with tampon use

The Staphylococcus aureus bacteria can also less commonly cause other infections, including pneumonia, ear infections, and sinusitis.

MRSA is an acronym for Methicillin-Resistant Staphylococcus aureus, a type of bacteria that has become resistant to many antibiotics, including methicillin, penicillin, amoxicillin, and cephalosporins. It is routinely pronounced M.R.S.A., not MUR-SA.

Although once limited to hospitals, nursing homes, and other healthcare facilities, MRSA infections are now very common among healthy children and adults in the community. Your pediatrician will likely suspect that an infection, such as a leg abscess, is caused by MRSA if it isn't improving with routine antibiotics. In that case, the abscess may need to be drained or your child would need to be changed to a stronger or different antibiotic to treat the infection.

The diagnosis of most skin infections is made by the pattern of symptoms and physical exam findings. However, it is not usually possible to know whether the infection is caused by a staph bacteria or another bacteria, like group A Beta-hemolytic streptococcus (Streptococcus pyogenes). And in many cases, it doesn't matter, as the antibiotic your child is prescribed will likely treat both bacteria.

To make a definitive diagnosis and to confirm that staph is the bacteria causing the infection, a culture can be done. Once a bacteria is identified in a culture, the pattern on sensitivities to antibiotics can help to tell whether or not it is actually MRSA, routine staph aureus, or another bacteria.

Antistaphylococcal antibiotics are the usual treatments for staph infections. This may include a topical antibiotic cream (Bactroban, Altabax, etc.) for simple impetigo, warm compresses, and drainage for abscesses, an oral antibiotic, or an intravenous antibiotic for more serious or persistent infections.

Commonly used oral antistaphylococcal antibiotics include the first-generation cephalosporins like Keflex (cephalexin) and Duricef (cefadroxil).

As resistance to antibiotics is now common among staph bacteria, including MRSA, the first antibiotic your child is prescribed may not work. Many of these community-acquired MRSA infections can still be treated with oral antibiotics, though, such as clindamycin and trimethoprim-sulfamethoxazole (TMP-SMX or Bactrim). More serious and multi-drug resistant MRSA can usually be treated in the hospital with the antibiotic vancomycin and/or surgical drainage.

Unfortunately, some staph infections, especially invasive MRSA infections, can be deadly.

Other things to know about Staph infections and MRSA include that:

• The S. aureus bacteria commonly live on or colonizes the skin of children and adults. It is especially common to find it in the nose, which can make it easily spread as children pick their nose.
• MRSA has become more common. It is thought that up to 2% of people are colonized with the MRSA bacteria.
• To get rid of staph colonization, it can sometimes help to treat all family members with mupirocin (Bactroban) nasal gel twice a day for 5-7 days, have everyone take weekly Hibiclens (an Antiseptic, Antimicrobial Skin Cleanser) or bleach baths, keep all wounds covered, and encourage very frequent handwashing.
• Although it can be uncomfortable for your child, having your pediatrician drain an abscess can be the best way to get rid of the infection.
• Zyvox (linezolid) is a newer antibiotic that can be used to treat complicated skin and soft tissue infections, including those caused by MRSA, in children. It is rather expensive though and would likely only be prescribed when other antibiotics either weren't working or the staph bacteria was known to be resistant to other more commonly used antibiotics, such as Bactrim and clindamycin.

Talk to your pediatrician if you think that your child might have a staph infection or if you are concerned about MRSA.