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What family is the Staphylococci

Microcococcaceae

Around how many species does the genus Staphylococcus contain?

35-40 species

Which couud be more dangerous: Coagulase positive species or Coagulase negative species

Coagulase positive species

What is an example of a coagulase positive Staphylococcus species?

S. aureus

What is an example of a coagulase negative Staphylococcus species?

S. epidermidis, S. saprophyticus, or S. haemolyticus.

What are some of the general characteristics of the Staphlyococcus genus?

1) Nonmotile

2) Non-spore-forming

3) Nonencapsulated

4) Catalase-producing

5) Oxidase: Negative

6) Glucose fermenters

7) Primarily aerobic, some facultatively anaerobic

8) Bacitracin resistant

9) Some are beta hemolytic

What percentage of the general populationare staph. carriers

20-30%

What does MRSA stand for?

methicillin resistant staph aureus

What damage can long-term Vacnimycin use cause?

kidney damage

What are the three modes of transmission for Staph. aureus?

Traumatic introduction (injury), Direct contact with infected person, Inanimate objects (bed rails and door handles)

What is pus?

a mix of active and inactive neutrophils, bacterial cells and extravascular fluid

What are the virulence factors of S. aureus?

Enterotoxins, Cytolytic toxinis, Enzymes, and Protein A

Coagulase postive species can convert [BLANK] to [BLANK]

Fibrinigin to fibrin

What are the two coagulase test?

Coagulase test tube method and slide method

Is coagulase freely secreted or organism bound?

Coagulase is both secreted/produced by the organism and organism bound (attached to the membrane)

What does Staphylococcus look like when gram stained?

Purple- gram positive. Morphology: clusters, grape like, and round shape

Is staphylococcus catalase positive or negative?

catalase positive

Is Staphylococcus motile and spore forming?

No to both, non motile and non spore forming

Is staphylococcus oxidase positive or negative?

negative, meaning that they lack the cytochrome C enzyme in the ETC

Is staphylococcus able to ferment glucose?

Yes, media will change from red to yellow with gas in the Durham tube to signify CO2

Are staphylococci facultative anaerobes?

Yes they prefer aerobic conditions but will tolerate anaerobic as well

What antibiotic is staphyloccus resistant to?

Bacitracin

What type of agar is used to grow staphyloccocus?

Agar with peptone

What type of media inhibits growth of staph?

Media with high bile salt concentration

Is staph able to be easily picked up by a loop?

Yes they are buttery looking, cream or white colored.

Strep. mutans is adheres to agarand needs to be cut out from

the agar.

Are all strains of staph B-hemolytic?

No, S. epidermidis is not but most strains of S. aureus are

beta hemolytic

Which type of staphylococcus species represent 20-30% of staph carriers?

Staphylococcus aureus

Can Staphylococcus aureus infect deep tissue?

Yes, because they are facultative anaerobes. Can lead to

bacterial sepsis if it enters the bloodstream (issue seen in 🏥 )

what areas can S. aureus colonize?

axilia, pharynx, and vagina

Where do people pick up staphylococcus infections ?

At hospitals, nosocomial frequently but can also be

community acquired

what condition can make them susceptible to Staphylococcus aureus infections?

Diabetics can have infections due to neuropathy (loss of feelings in feet).

What are types of enterotoxins? (Staph).

Exfoliatin, TSST-1 (toxic shock syndrome toxin-1), and cytolytic toxins.

What are the extracellular enzymes that are virulence factors

In staph.

Hylaronidase, staphylokinase, coagulase, lipase, pencillinase, DNase, beta-lactamase.

What is the result of a S. aureus infection specifically in the skin?

Bullous impetigo, furuncles, carbuncles.

Where could a person get a staph aureus infection on their skin?

Gyms, surgical wound, and prisons

What causes scalded skin syndrome?

Staphylococcus aureus exfoliative toxin, seen in newborns and young children

(True or False) Toxic shock syndrome only affects the kidneys.

FALSE. Multisystem,affecting numerous organ systems caused by

TSST-1 (affects everyone)

Why does staphyloccocus aureus show up in food poisoning cases?

Food such as meat, milk, mayo and baked goods with cream fillings are rich in nutrients. Grows well in chopped

Meat agar for isolation of organism.

What is the appearance of an epithelial cell?

Flat fried eggs appearance, tend to shed, coated in cocci.

What type of culture is collected is collected to identify Staphylococcus sacrophyticus?

A urine culture is collected, UTIs are common with this infection

What are the predisposing conditions associated with S. aureus infection?

Chronic infections, indwelling devices (catheter), skin injuries(break in skin), immune response defects

What are the characteristics of Strepococci?

Gram positive, 1um in diameter, chains or pairs, usually unencapsulated, non-motile, non-spore forming, facultative anaerobes, fastidious, catalase negative

Streptococci are classified according to:

Oxygen requirements, Serology, and hemolysis

What organism is in Group A strep?

Strep. pyogenes

What organism is in Group B Strep?

Strep. agalactiae

What Streptococci looks like a string of pearls under the microscope?

S. pyogenes

What are the two non-groupable streptococci?

S. pneumoniae and S. viridans

What Streptococci is in group D?

Enterococcus spp.

What is the arrangement of S. pneumoniae?

Diplococcus

What bacteria belongs to the mutans Streptococci group?

S. mutans

What are the other names for S. pneumoniae?

The diplococcus or The pneumococcus

What Strep. species tends to be capsulated?

S. pneumoniae

What bacterium is responsible for 90% of cases of pharyngitis?

S. pyogenes

What is the peak incidance age range for Group A streptococci?

5-15 years of age

Give two diseases that can be caused by S. pyogenes?

Strep throat, Impetigo, Erysipelas, Cellulitis, Invasive Strep A infections (Necrotizing fasciitis, Myositis, Toxic shock-like syndrome

What is eryspelas?

an acute infection and inflammation of the dermal layer of skin. Painful red patches which enlarge and thicken

What is the most common of all strep diseases?

Strep throat

How is strep throat spread?

Saliva or nasal secretions

What is the incubation period for strep throat?

2-4 days

What are the symptoms of strep throat?

sore throat, slight fever, visual of pus in back of throat

What does it mean for a strain to be lysogenic?

This strain has been invaded by a particular bacteriophage capable ofproducing toxins, this capability is passed to the bacterial strain

What makes a S. pyogenes strain cause Scarlet fever?

A bacteriophage infection that allows for the bacteria to produce an erythrogenic toxin

What are examples of poststreptococcal diseases?

Rheumatic Fever and Acute glomerulonehritis (Bright's Disease)

What is acute glomerulonehritis (Bright's Disease)?

Inflammatory disease of renal glomerulli and structures involved in blood filter of kidney.

What is the most common cause of permanent heart valve damage in children?

Rheumatic Fever

What is Rheumatic Fever?

1. it is an inflammatory disease that may develop after an infection with streptococcus bacteria (such as strep throat or scarlet fever)

What is one of the first proteins you will see in the urine from glomerulonephritis?

Albumin

Glomerulonephritis occurs in \___% of those having strep throat?

0.5% (or 1 in every 200)

What are the symptoms of Glomerulonephritis?

fever, malaise, edema, hypertension and blood or protein in urine

T/F. Kidney damage in the remainder of glomerulonephritis is permanent.

True, it results in chronic glomerularnephritis

What % of glomerulonephritis cases recover with bed rest lasting for months

80-90

S. pneumoniae is a gram \_____, \_____ hemolytic streptococcus.

positive, alpha

What is an endogenous infection?

infection from microbial life inside the person

What is the primary virulence factoro for Strep. pneumoniae?

It's capsular polysaccharide, protects the organism against phagocytosis

What is needed for Strep. pneumoniae to grow?

CO2

Where an S. pneumoniae rapidly grow?

In alveolar spaces

What are the two age groups that S. pneumo likes to infect?

The young and the elderly

What components helps protect S. pneumoniae and increases its viulence factors?

M protein (interrupts opsonization and bacterial lysis)

Lipoteichoic acid and F protein (adhesion)

Hyaluronic acid capsule ( camouflage)

What are the three enzymes that S. pneumoniae can utilize for further bacterial spread?

Streptokinases, Deoxynucleases, C5a peptidase. All break down tissues to allow for deeper streptococci penetration

What are the Streptolysins?

Streptolysin O and Streptolysin S

What

The attachment of antibodies to the antigen on the surface of an organism

What does Streptolysin O do?

Lyses RBCs, WBCs, and platelets