An abscess is a collection of pus that has built up within the tissue of the body. Signs and symptoms of abscesses include redness, pain, warmth, and swelling. The swelling may feel fluid-filled when pressed. The area of redness often extends beyond the swelling. Carbuncles and boils are types of abscess that often involve hair follicles, with carbuncles being larger.
Staphylococcus aureus is a Gram-positive round-shaped bacterium, a member of the Firmicutes, and is a usual member of the microbiota of the body, frequently found in the upper respiratory tract and on the skin. It is often positive for catalase and nitrate reduction and is a facultative anaerobe that can grow without the need for oxygen. Although S. aureus usually acts as a commensal of the human microbiota it can also become an opportunistic pathogen, being a common cause of skin infections including abscesses, respiratory infections such as sinusitis, and food poisoning. Pathogenic strains often promote infections by producing virulence factors such as potent protein toxins, and the expression of a cell-surface protein that binds and inactivates antibodies. The emergence of antibiotic-resistant strains of S. aureus such as methicillin-resistant S. aureus (MRSA) is a worldwide problem in clinical medicine. Despite much research and development, no vaccine for S. aureus has been approved.
A boil, also called a furuncle, is a deep folliculitis, infection of the hair follicle. It is most commonly caused by infection by the bacterium Staphylococcus aureus, resulting in a painful swollen area on the skin caused by an accumulation of pus and dead tissue. Boils which are expanded are basically pus-filled nodules. Individual boils clustered together are called carbuncles. Most human infections are caused by coagulase-positive S. aureus strains, notable for the bacteria's ability to produce coagulase, an enzyme that can clot blood. Almost any organ system can be infected by S. aureus.
Staphylococcus haemolyticus is a member of the coagulase-negative staphylococci (CoNS). It is part of the skin flora of humans, and its largest populations are usually found at the axillae, perineum, and inguinal areas. S. haemolyticus also colonizes primates and domestic animals. It is a well-known opportunistic pathogen, and is the second-most frequently isolated CoNS. Infections can be localized or systemic, and are often associated with the insertion of medical devices. The highly antibiotic-resistant phenotype and ability to form biofilms make S. haemolyticus a difficult pathogen to treat. Its most closely-related species if Staphylococcus borealis.
Staphylococcus saprophyticus is a Gram-positive coccus belonging to the genus Staphylococcus. S. saprophyticus is a common cause of community-acquired urinary tract infections.
Staphylococcus hominis is a coagulase-negative member of the bacterial genus Staphylococcus, consisting of Gram-positive, spherical cells in clusters. It occurs very commonly as a harmless commensal on human and animal skin and is known for producing thioalcohol compounds that contribute to body odour. Like many other coagulase-negative staphylococci, S. hominis may occasionally cause infection in patients whose immune systems are compromised, for example by chemotherapy or predisposing illness.
Peptostreptococcus is a genus of anaerobic, Gram-positive, non-spore forming bacteria. The cells are small, spherical, and can occur in short chains, in pairs or individually. They typically move using cilia. Peptostreptococcus are slow-growing bacteria with increasing resistance to antimicrobial drugs. Peptostreptococcus is a normal inhabitant of the healthy lower reproductive tract of women.
Mycobacterium abscessus complex (MABSC) is a group of rapidly growing, multidrug-resistant, nontuberculous mycobacteria (NTM) species that are common soil and water contaminants. Although M. abscessus complex most commonly causes chronic lung infection and skin and soft tissue infection (SSTI), the complex can also cause infection in almost all human organs, mostly in patients with suppressed immune systems. Amongst NTM species responsible for disease, infection caused by M. abscessus complex are more difficult to treat due to antimicrobial drug resistance.
The term skin flora refers to the microorganisms which reside on the skin, typically human skin.
Staphylococcus is a genus of Gram-positive bacteria in the family Staphylococcaceae from the order Bacillales. Under the microscope, they appear spherical (cocci), and form in grape-like clusters. Staphylococcus species are facultative anaerobic organisms.
Staphylococcus cohnii is a Gram-positive, coagulase-negative member of the bacterial genus Staphylococcus consisting of clustered cocci. The species commonly lives on human skin; clinical isolates have shown high levels of antibiotic resistance. A strain of S. cohnii was found to contain a mobile genetic element very similar to the staphylococcal cassette chromosome encoding methicillin resistance element seen in Staphylococcus aureus.
Staphylococcus condimenti is a Gram-positive, coagulase-negative member of the bacterial genus Staphylococcus consisting of single, paired, and clustered cocci. Strains of this species were originally isolated from fermenting soy sauce mash and are positive for catalase, urease, arginine dihydrolase, nitrate reductase, beta-galactosidase, and phosphatase activity.
Staphylococcus carnosus is a Gram-positive, coagulase-negative member of the bacterial genus Staphylococcus consisting of single and paired cocci. Its genome has the highest GC content - 36.4% - of any sequenced staphylococcal species.
Staphylococcus equorum is a gram-positive, coagulase-negative member of the bacterial genus Staphylococcus consisting of clustered cocci. Originally isolated from the skin of healthy horses, this species contains a cell wall similar to that of Staphylococcus xylosus.
Staphylococcus hyicus is a Gram-positive, facultatively anaerobic bacterium in the genus Staphylococcus. It consists of clustered cocci and forms white circular colonies when grown on blood agar. S. hyicus is a known animal pathogen. It causes disease in poultry, cattle, horses, and pigs. Most notably, it is the agent that causes porcine exudative epidermitis, also known as greasy pig disease, in piglets. S. hyicus is generally considered to not be zoonotic, however it has been shown to be able to cause bacteremia and sepsis in humans.
Staphylococcus piscifermentans is a Gram-positive, coagulase-negative member of the bacterial genus Staphylococcus consisting of clustered cocci. This species was originally isolated from fermented fish in Thailand. A later study found a strain of S. piscifermentans in dog feces. The species is used in the preparation of fermented foods along with Staphylococcus carnosus; both species reduce nitrate and produce ammonia.
Staphylococcus schleiferi is a Gram-positive, cocci-shaped bacterium of the family Staphylococcaceae. It is facultatively anaerobic, coagulase-variable, and can be readily cultured on blood agar where the bacterium tends to form opaque, non-pigmented colonies and beta (β) hemolysis. There exists two subspecies under the species S. schleiferi: Staphylococcus schleiferi subsp. schleiferi and Staphylococcus schleiferi subsp. coagulans.
Staphylococcus pseudintermedius is a gram positive coccus bacteria of the genus Staphylococcus found worldwide. It is primarily a pathogen for domestic animals, but has been known to affect humans as well.S. pseudintermedius is an opportunistic pathogen that secretes immune modulating virulence factors, has many adhesion factors, and the potential to create biofilms, all of which help to determine the pathogenicity of the bacterium. Diagnoses of Staphylococcus pseudintermedius have traditionally been made using cytology, plating, and biochemical tests. More recently, molecular technologies like MALDI-TOF, DNA hybridization and PCR have become preferred over biochemical tests for their more rapid and accurate identifications. This includes the identification and diagnosis of antibiotic resistant strains.
Janibacter is a genus of Gram positive, nonmotile, non-sporeforming bacteria. The genus name is derived from the two-faced Roman god Janus, referring to the fact that the cells of the original strain could be rod-shaped or coccoid.
Staphylococcus borealis is a bacterial species, member of the genus Staphylococcus, closely-related to Staphylococcus haemolyticus and described in 2020. Its cells are Gram positive, coccoid in shape, with a diameter of 0.65 to 1.23 µm and form clusters. Additionally, they are facultative anaerobic, coagulase negative and catalase positive. The type strain was isolated from human blood culture at the University Hospital of North Norway, in 1997. Four additional strains included in the description were isolated from skin swabs, from healthy volunteers. The genome sequence of the type strain is deposited in DNA Data Bank of Japan, European Nucleotide Archive and GenBank under the accession number JABVEJ000000000.
