Chp 19, Lect 2
Bacteria diseases of the skin and wounds folliculitis
infection of hair follicle
Furuncle
A large painful raised nodular extensions of folliculitis result in spread of infection surrounding tissues
When furuncles join together they make carbuncle
Most common cause of folliculitis and associated functions is staphylococcus
Gram-Positive anaerobic bacteria where the spherical cells are clustered in grap arrangements
Staphylococcus
Epidermidis
Major member of microbiome accounting for 90% of bacteria on skin
Aureus
virulent pathogen grows nasal passages and produces a wide variety of disease conditions and symptoms
Staohylococci
3 categories of virulence factors allow them to make disease
Enzymes
virlence strains of S. Aureus
Coagulase clots blood which hide the bacterium from phagocytosis
Stapylokinase
Dissolves blood clots which allows staph to spread to new locations
Lipases
Presents in S. epidermidis digest lipids providing pathogen with food on surface of skin, hair follicles, and in sebaceous glands
B- Lactamase
Gives resistance to many beta-lactam antimicrobial drugs like PCN and cephalosporin
Both of these avoid bodies defense by creating loosely organized polysaccharide slime layers stop chemotaxis pf phagocytosis by leukocytes
Cytolytic toxins
Disrupt the cells membrane
This is transmitted via direct contact or by fomites
Can spread into hypodermis to form furuncle or into other hair follicles to form carbuncle. Can spread into blood