Vancomycin Sensitive S. aureus, VISA and VRSA

Most Staphylococcus aureus strains are sensitive to antibiotic vancomycin. The concentration of vancomycin required to inhibit these strains (minimal inhibitory concentration - MIC) is 0.5-2 micrograms/mL. S. aureus strains for which vancomycin MICs are 4-8 micrograms/mL are classified as Vancomycin Intermediate Staphylococcus aureus - VISA, and strains for which vancomycin MICs is equal or exceeds 16 micrograms/mL are classified as Vancomycin Resistant Staphylococcus aureus – VRSA (1).

continue reading Vancomycin Resistant Staphylococcus Aureus ~ VRSA (and VISA)

What is a Superbug?

Superbugs, also called Multi Drug Resistant (MDR) bacteria, are resistant to several antibiotics. Not all superbugs necessary cause a severe infection though. One common superbug is MRSA.

What is MRSA?

Methicillin Resistant Staphylococcus aureus (MRSA) is a strain (a genetic variant within the same species) of Staphylococcus aureus bacterium, resistant to antibiotic methicillin, and other antibiotics from the same class as penicillin, amoxacillin, and oxacillin. The main problem with MRSA is that it is often not recognized as such, and hence treated with inappropriate antibiotics (1, page 25).

MRSA Related Terms

MRSA= Methicillin Resistant Staphylococcus aureus (Common misspelling: MERSA, MRCA, MERCA)
HA-MRSA = Healthcare Associated MRSA
CA-MRSA = Community Associated MRSA,
CO-MRSA = Community Onset MRSA, and HO-MRSA is Hospital Onset MRSA, terms describe the source of infection when found in a healtcare unit. 
EMRSA = Epidemic MRSA ~ MRSA strain easily spreading among patients and hospitals
MRSE = Methicillin Resistant Staphylococcus Epidermidis
VRSA = Vancomycin Resistant Staphylococcus Aureus
MSSA = Methicillin Sensitive Staphylococcus Aureus, this is an usual S. aureus, shortly SA
Staph = short for all types of staphylococci (staph aureus, staph epidermidis, staph infection)

MRSA virus is a commonly used term that is obviously incorrect, since MRSA is a bacterium.

continue reading MRSA Superbug Types: CA-MRSA, HA-MRSA in Y. 2008

MRSA and “Usual” Staph Aureus Pictures

It’s impossible to say from staph skin infection pictures, if the cause of infection is MRSA (Methicilin Resistant Staphylococcus Aureus) or an “usual” staph - MSSA (Methicillin Sensitive Staphylococcus Aureus). Even a staph carrier without any symptoms can have MRSA.  Folliculitis, which is usually a mild infection, may also be caused by MRSA or MSSA (folliculitis pictures).

Picture 1. A boil below the knee, caused by MRSA
(source: phil.cdc.gov)

continue reading MRSA Staph Infection Pictures

Staph Infection Symptoms

Staph infection symptoms include various skin changes, symptoms related to infected internal organs, and symptoms relateed to staph blood poisoning – sepsis.

What is Staph?

Staph infection is caused by bacterium Staphylococcus aureus (shortly staph), and rarely by S. epidermidis or other staphylococcal species.

What is Staph Infection?

Staph infection is inflammation of the skin or internal organs, caused by staph bacteria or their toxins. Staph infection may be mild or life threatening, and may appear as:

• staph skin infection
• staph infection of mucous membranes (sinusitis, epiglottitis, vaginitis)
• staph gland infections (mastitis, parotitis) 
• staph food poisoning
• staph urinary infection in men
• staph bone infection (osteomielitis) and joint infection (arthritis)
• staph pneumonia
• bacterial endocarditis
• staph meningitis
• bacteremia, septicemia
• soft tissue gangrene and gas gangrene
• staphylococcal toxic shock syndrome

continue reading Staph Infection Symptoms

Staph Skin Infection Pictures

Staph (pronounced ’staff’) skin infection may appear as

• a red bump or pus-filled blister (folliculitis)
• a boil (furuncle)
• infected cystic acne, hidradenitis suppurativa, pilonidal cyst
• a vesicle which may burst and crust over (impetigo)
• erythema (cellulitis)
• skin scalding (staphylococcal scalded skin syndrome)
• an infected wound or burn

Drainage of pus from lesions is common.

What Causes Staph Skin Infections?

Staph infections are mainly caused by bacterium Staphylococcus aureus, and rarely by S. epidermidis, or S. saprophyticus. In staph carriers, S. aureus, lives in the nose and on the skin, and less commonly in the mouth, mammary glands, urinary, intestinal, and upper respiratory tracts (1). Staphylococcal infections usually remain localized at the portal of entry. What is Staphylococcus aureus?

continue reading Staph (Staff) Skin Infections Pictures

Folliculitis Pictures

Pictures in this article show staphylococcal folliculitis. Links to pictures of other types of folliculitis.

Picture 1. Staphylococcal folliculitis appears as a red bump, or white pustule.
(source: Samuel Freire da Silva, M.D., Atlasdermatologico)

Picture 2. Staphylococcal folliculitis on the woman’s chest
Click to enlarge >> © Dermnet

Picture 3. Staphylococcal folliculitis on thighs
Click to enlarge >> © Dermnet

continue reading Folliculitis Pictures

Staphylococcus aureus

Staphylococcus aureus (Greek staphyle = bunch of grapes, Latin coccus = spherical bacterium, aureus = golden), or golden staph (pronounced ’staff’), is the most common staphylococcus species causing infections in human.

Lab Tests for Staph
Staph Epidemiology

Staph Infections

S. aureus lives as the part of the normal skin flora in the nose or on the skin in 20-30% of healthy people (staph carriers), (1). However, in even slightly injured skin or mucosa, staph may cause styes, pimples, folliculitis, furuncles, boils (picture 1), swimmer’s ear, sinusitis, epiglotitis, whitlow, breast infection, impetigo, cellulitis, genital infection, or scalded skin syndrome. Infections of internal organs include urinary tract infections, arthritis, pneumonia, infection of veins (thrombophlebitis), lymph nodes (lymphadenitis) or lymph vessels (lymphangitis), bone infection (osteomyelitis) (picture 2), or life threatening  sepsis (staph blood invasion), infection of heart valves (endocarditis),  meningitis, “flesh eating bacteria” infection (necrotizing fasciitis), and toxic shock syndrome. S. aureus enterotoxins may cause food poisoning.

S. aureus and S. epidermidis are among the most common causes of hospital-acquired infections like bloodstream infections, infections of surgical wounds, or pneumonia (2). Staph may also appear in vascular and urinary catheters, prosthetic joints, and heart valves.

Staph skin infection usually appears as a red, warm, painful swelling with a blister, ulcer, or crust, and a drainage (picture 1). Infection may spread into deeper tissues, like bones (picture 2).

Picture 1. A boil on the upper arm	Picture 2. X-ray of child’s legs: osteomyelitis in shin bones (grey patches)

continue reading What is Staphylococcus Aureus?