staph Flashcards
Is staphylococcus gram positive cocci?
yes
is neisseria gram positive cocci?
no
is moraxella gram positive cocci?
no
is veillonella gram positive cocci?
no
is streptococcus gram positive vocci?
yes
is micrococcus gram positive cocci?
yes
morphologically round in shape and is color violet/purple
gram positive cocci
is a biological kingdom that is made up of
prokaryotes, particularly bacteria. it lacks nucleus
monera
small pinpoint colonies
steptrococcus
appears in cluster
staphylococcus
obligate aerobe
micrococcus
facultative anaerobe
streptococcus, and staph
medium large, pinhead colonies
staphylococcus
small-medium colonies, not pinhead, not pin-oint
micrococcusq
non hemolytic genus
micrococcus
beta-hemolytic genus
staphylococcus
alpha, beta, gamma hemolysis
streptococcus
among the three’ micrococcus, staph and strep. Which are the catalase positive and catalase negative
catalase positive are the micrococcus and staphylococcus
catalase negative is streptococcus
the genus staphylococcus is deriveed from the greek word __ meaning brabches of grapes
staphle
among the staphs, which are the only pathogenic to human that is COAGULASE POSITIVE
Staphylococcus Aureus
staphylococcus:
golden-yellow colonies; pathogenic
S. Aureus
staphylococcus:
white pigment, a chromogenic opportunistic pathogen
S. citreus
staphylococcus:
white pigment only
S. albus
staphylococcus:
animal pathogen
S. hyicus
staphylococcus:
predominant normal flora on the skin;leading cause of iantrogenic infection
S. epidermis
staphylococcus:
opportunistic pathogen; normal flora of skin that is frequently cause of UTI , abortion/miscarriages
S. saprophyticus
staphylococcus:
recovered in wounds
S. haemolyticus
Common inhabitant of the skin and mucous
membranes, responsible for several suppurative
infections
staphylococcus
Gram-positive cocci, catalase-positive
staphy and micro
Spherical cells arranged in irregular clusters, appear
singly, in pairs
staphy
is staphy motile?
No, it cannot move
is staphy spore forming?
no
In staphy, aerobic or facultative anaerobic except for one specie that is obligate anaerobe. What is it
S. saccharolyticus
“buttery looking”, cream colored, medium sized of 4-8 mm, white nad rarely gold
staph
Is the most dangerous of all the many common
staphylococcal bacteria.
S. aureus
coagulase postive of staph
S. aureus
It causes various cutaneous infections and purulent
abscesses.
- These cutaneous infections can progress to
deeper abscesses involving other organ systems
and produce bacteremia and septicemia.
s. aureus
S. lugdunensis and S. schleiferi –
mistaken as coagulase positive
staphylococci because of the presence of
clumping factor
virulence factors of s.aureus
cytolytic toxins
-hemolysin
enterotoxins
toxic shock syndrome
epidermolytic toxin (exfoliative toxin)
fibrolysin/staphylokinase
protein a and polysaccharide a
staphylocoagulase
hyaluronidase
lipase
dnase
hemolysin belongs to cytolytic toxins. hemolysin compoosed of alpha, betta, gamma. and delta. it primary destroys what?
RBC liberating hemoglobin
hemolysin that damage platelets and
macrophages and can cause severe tissue
damage
alpha hemolysis
beta hemolysin is also known as
sphingomyelinase C
eta acts on the
sphingomyelin in plasma membrane of
erythrocytes and is also called as the HOT COLD LYSINE
beta hemolysin or SPHINGOMYELINASE C
another type of cytolytic toxins that is primary for rupturing WBC, it is called
panton-valentine toxin/leukocidin
are responsible for the manifestations of staphylococcal
food poisoning; heat stable; it has A, B, and Da
enterotoxin
a virulence factor that causes toxic shock
syndrome a Severe and often fatal disorder
characterized by multiple organ dysfunction
Toxic Shock Syndrome Toxin-1 (TSTT-1)
Formerly known as Enterotoxin F and pyrogenic
exotoxin C
Toxic Shock Syndrome Toxin-1 (TSTT-1)
Responsible for the staphylococcal scalded skin
syndrome (SSS) sometimes referred to as Ritter
disease.
Epidermolytic Toxin (Exfoliative Toxin)
- responsible for lysin clot
- activates plasminogen to form plasmin which
digests the vibrant clots
Fibrolysin/Staphylokinase
block phagocytosis and negate the protective
effect of the G (IgG)
Protein A and Polysaccharide A
is a relatively mild inflammation of hair
follicle or oil gland; infected area is raised and red
Folliculitis
extension of folliculitis; large, raised and
superficial abscess
- in tagalog it is called pigsa
furuncles (boils)
- cluster of boils
- often present with fever and chills indicating that
the infection is spread systemically or in the blood
carbuncles
larger than streptococcal non-bullous impetigo;
surrounded by a small zone of erythema
Bullous impetigo
- is highly contagious infection that isn’t spread by
direct contact, fomites or auto inoculation
Bullous impetigo
Toxic Shock Syndrome (TSS)
- Is a toxin with gated acute life-threatening illness
caused by the
enterotoxin F.
affects menstruating women especially those
who use super absorbent tampons the body
responds with a sharp drop in blood pressure that
deprives the organs of oxygen and can lead to
death.
Toxic Shock Syndrome (TSS)
Fatal, multisystem disease characterized by
sudden onset of fever, chills, vomiting, diarrhea,
muscle aches and rash (predominantly on the
trunk)
Toxic Shock Syndrome (TSS)
produced by the
staphylococcus aureus is responsible for the
disease scalded skin syndrome
Exfoliative Diseases
- Epidermolytic toxin
The toxin is metabolized and excreted by
the kidneys and investigators believe this may be
the reason why the incidence of SSS is higher
among children younger than five years old and among adults with chronic renal failure and
impaired immune system
epidermolytic toxin (Exfoliative Diseases)
the best sample for staphyloccus aureusq
aspirate sample, a single swab would be less satisfactory for bith culture and smear results
or large gram positive cocci usually
arranged in tetrads or in pairs
Micrococcus
produce golden-yellow
(aureus) pigment (staphyloxanthin)
- White-colony strains of S. aureus are
fully virulent. according to the characteristics, where does s.sureus cultured
nutrient agar
identification of S. aureus in MIXED CULTURES
Phenolphthalein Phosphate Agar (PPA)
small- to medium-sized,
nonhemolytic, gray-to-white colonies; some weakly
hemolytic
S. epidermis
slightly larger colonies, with about
50% of the strains producing a yellow pigment
s. saprophyticus
medium sized colonies, with
moderate or weak hemolysis and variable pigment
production
s. haemolyticus
demonstrate the presence of catalase
an enzyme that catalyzes the release of oxygen from
hydrogen peroxide (H2O2)
catalase test
reagent used in catalase test
3% H2O2 is used for the routine culture
- While 15% hydrogen peroxide is used for the
detection of catalase in an aerobe.
positive result of catalase test
bubbles formation or effervescence
Best single pathogenicity test for staphylococcus
coagulase (slide or tube method)
is a biochemical test that is used
to differentiate staphylococcus aureus from other
staphylococci species
Coagulase test
positive relut in slide method (screening test) for coagulation
agglutination
Because about five percent
of staphylococcus aureus organisms do not produce
clamping factors any negatives like coagulase test results
must be confirmed with the .
tube method
hrs of incubation for tube method
2 hrs then 4 then 24 hrs
uses Hugh and Leifson’s Medium
Oxidation-Fermentation (O/F) Reactions
, meaning
absence it will not produce acid in either of
the tube
Asaccharolytic organism
Modified Oxidase Test
- Active Chemical component is )_______
Tetra-methyl-paraphenylene diamine dihydrochloride
in modified-oxidase test (+) = blue to purple to black complex
[Micrococci]
positive result and indicator of mannitol fermentation
yellow and phenol red
positive result and indicator of mannitol fermentation
yellow agar and phenol red
Gelatinases are proteases secreted
extracellularly by some bacteria which hydrolyze
or digest gelatin.
Gelatin Liquefaction/Hydrolysis Test
Staphylococcus ____ is
resistant to novobiocin whereas most other coNs
are susceptible
saprophyticus
most common cause of prosthetic valce endocarditis
S. epidermis
UTIs in young women
Staphylococcus saphrophyticus
Staphylococcus has been known to contain the gene
MECA that encodes oxacillin resistance
S. lugdunensis
Cloxacillin, oxacillin, flucloxacillin
are used as
penicillinase resistant penicillin.
(vancomycin or teicoplanin) are the
agents of choice in the treatment of systemic infection, but
these agents are expensive and may be toxic.
glycopeptides
is responsible for several difficult to treat
infections in humans. It is sometimes called the
superbug..
Methylene resistant staphylococcus aureus
such as
the oxacillin resistance screening agar can be
used as a screening test for MRSA in clinical
samples
an oxacillin-salt agar plate
is a better inducer of mecA mediated
resistance.
Cefoxitin
is a drug of choice and sometimes the only
drug available for serious staphylococcal infections
Vancomycin
a macrolide, is frequently used in
staphylococcal skin infections; additional testing using a
modified double disk diffusion test (D-zone test) might be
useful
clindamycin
Only two species, Micrococcus ____and Micrococcus
___, remain in the genus.
luteus, lylae
