Bacteria: Aerobic Gram Positive Cocci

Front 1

-Gram positive cocci positive for catalase test
-Gram positive cocci negative for catalase test

Back 1

-Staphylococcus
-Streptococcus or Enterococcus

Front 2

Staphylococcus positive for coagulas test

Back 2

S. aureus, rest known as coagulase negative staphylococci.

Front 3

What is the catalase test?

Back 3

Detects presence of enzyme catalase which converts hydrogen peroxide to oxygen (produces bubbles) and water.

Front 4

Genus Staphylococcus
-species

Back 4

-aureus, epidermidis, saprophyticus

Front 5

What is the coagulase test?

Back 5

Detects presence of enayme coagulas which converts fibrinogen to fibrin in basis of blood clot.

Front 6

Staphylococcus aureus
-carriage and %
-problems with carriage

Back 6

-Anterior nares and 20-40% of popn.
-Most nothing, some chronic skin infections

Front 7

Infections associated with S. aureus

Back 7

· Skin lesions: folliculitis, furuncles (boils), carbuncles, impetigo, cellulitis, hidradenitis suppurativa.
· Mastitis
· Wound infections
· Bacteraemia and septicaemia:serious cause of death
· Osteomyelitis
· Septic arthritis
· Septic bursitis
· Endocarditis.

Front 8

What other some other pyogenic infections cause by S. aureus?

Back 8

Pneumonia, pleural empyema, pyomyositis, brain abscess, renal abscess,
pericarditis, vertebral disc space infection.

Front 9

What are three other important infections caused by S. aureus?

Back 9

• Staphylococcal scalded skin syndrome (SSSS): Exfoliative toxin (EF).
• Staphylococcal toxic shock syndrome (STSS):
Toxic Shock Syndrome Toxin-1 (TSST-1).
• Staphylococccal food poisoning: Vomiting, cramping, diarrhoea, usually watery

Front 10

Staphylococcus epidermidis
-commensal of
-infections
-main virulence factor

Back 10

-Skin
-Infections of IV causing red, oozy skin, bacteraemia and fever, prosthetic joint infection resulting in pain, redness and swelling of soft tissue and erosion of bone, infection of pins, plates etc, meningitis.
-slime (allowing bacteria to adhere and colonise on foreign surfaces) forming a biofilm

Front 11

Staphylococcus saprophyticus
-causes

Back 11

-2nd major cause of UTI in young, sexually active females

Front 12

What test determines the differences between streptococci groups?
What are the two types and what results would you expect?

Back 12

-Haemolysis
-Beta: complete haemolysis, transparent agar (no erythrocytes) around colony and alpha:partial haemolysis around each colony green (viridians) discolouration

Front 13

What are the beta haemolytic groups divided into and based on what?

Back 13

Lancefield groups as a result of antigenic differences in cell wall carbohydrates

Front 14

What is another name for Lancefield group A streptococci?
Where is it a commensal?
What does it cause?

Back 14

-Streptococci pyogenes
-Oropharynx
-Pharyngitis & tonsollitis with suppurative complications such as peritonsillar abscess, retropharyngeal abscess, otitis media, sinusitis, mastoiditis, septicaemia; cellulitis, erysipelas (raised erythema often on face), streptococcal pyoderma (crops of pustules coalescing to form thick ulcers), necrotising fasciitis (invasive subcutaneous and fascis infection associated with necrosis and gangrene, puerperal sepsis (invasion of uterus after childbirth.)

Front 15

What are the three non-suppurative comlications of Lancefield group A streptococci?

Back 15

Rheumatic fever: autoimmune, causing carditis, polyarthritis, subcutaneous nodules, erthyema marginatum, chorea.
Post streptococcal glomerulonephritis: inflammatory disease of glomeruli cause lesions, hypertension, haematuria, proteinuria.
Toxic shock-like syndrome: toxin mediated after invasive infection causin hypotensive shock, renal dysfunction, hypoalbuminuria, thrombocytopaenia and respiratory failure.

Front 16

What is the other name for Lancefield group B streptococci?
What is it a commensal of?

Back 16

Streptoccocus agalactiae
Vagina

Front 17

What infections can P. agalactiae cause?
What antibiotics is given to prevent early labour?

Back 17

Early onset in utero: septicaemia, bacteraemia, septic shock, pneumonia, meningitis
Late onset: bacteraemia with meningitis
Mother:postpartum endometritis, post Cesarean section bacteraemia
-IV amoxycillin

Front 18

What are the three species of Lancefield group C?
What does it cause?

Back 18

-S. equisimilis, S. zooepidemicus, S. equi
-Exudative pharyngitis and tonsillitis

Front 19

What are the species of Lancefield group D?
What does it cause?
What does it indicate when in bloodstream?

Back 19

-S equinis and S. bovis
-Bacteraemia and endocarditis.
-Colonic malignancy.

Front 20

Which group in the British system comes under Lancefiled group F?
What does Lancefield group F cause?

Back 20

S. milleri
-Bacteraemia, endocarditis, osteomyelitis, deep tissue abscesses.

Front 21

What three species compromise the milleri group?

Back 21

S. anginosis (beta), S. constellatus (alpha), S. intermedius (alpha)

Front 22

Aside from specis of the milleri group which other species compromise alpha-haemolytic group?
What are they commensals of?

Back 22

S. mutans, S. mitis, S. sanguis, S. salivarius, S. oralis
-Oropharyngeal and genital tract

Front 23

What infections fo the alpha haemolytic group cause?

Back 23

Infective endocarditis (partiucular after dental work in abnormal valves), abscess (oro-facial, pulmonary, pleural, intrabdominal and brain, dental caries

Front 24

How does S. mutans and other species cause dental caries?

Back 24

Glucosyltransferases produce glucans which adheres to teeth and forms basis of plaque-biofilm.

Front 25

What is the other main streptococcus species not in alpha or beta haemolytic group?
What is it a commensal of and %?
What makes it virulent?

Back 25

S. peumoniae
-Upper respiratory tract in 5-10%
-Polysaccharids capsule

Front 26

What disease does Streptococcus pneumoniae cause?

Back 26

Pneumonia-in healthy, community acquired adults and meningitis-most common cause of it in healthy adults.

Front 27

Main species of Enterococcus responsible for pathogens? Which is more common? Which is more resistan?
Main infections?

Back 27

-E. faecalis is more common and E. faecium is more resistant
-Intrabdominal infections due to soiling of peritoneum, (polymicrobial) UTI, soft tissue infections such as diabetic ulcers, burns, surgical wounds, bacteraemia and endocarditis.