micro 1

which is only found in gram negative bacteria

periplasmic space

acid used to liberate antigen off organism cell wall, enhances visualization of ab ag reaction

lancefield grouping test

loefflers medium

direct inoculation of c diptheria swabs, contains serum and egg

cystine tellurite blood agar

cystein enhances growth of organism and tellurite inhibits normal flora

antibiotic that inhibits cell wall synthesis

bacitracin taxo a

used for differentiation of beta hemolytic strep

bacitracin taxo a

antiboiotics that inhibit folate synthesis pathway, affecting production of dna for bacterial replicatioj

trimethoprim and sulfamethoxazole

detects antibodies in patient serum due to foreign microbial antigens

serology

antibodies used in serology

antistreptolysin ASO, anti streptokinase, anti dnase B

streptococci C and G colonization

nasopharynx, skin, gi tract, genital tract

streptococci c and g infection

bacterial pharyngitis

streptococci transmission

direct contact and endogenous strain

yeast normal flora

oral cavity, skin, gi traft, vagina

corynebacterium diptheria colonizes

nasopharynx

subspecies of c diphtheria

gravis, mitis, intermedius, belfanti

corynebacterium diptheria infection

diptheria

thick exudate pseudomembrane in throat that can interfere with breathing and release toxins

diptheria

transmission of corynebacterium diptheria

droplets or contact with exudate lesions

corynebacterium diptheria virulence mechanisms

exotoxins that inhibit protein synthesis in cells causing apoptosis

corynebacterium diptheria treatment

penicillin or anti toxin

vaccine with diptheria toxoid, pertussis, tetanus

Dtap

rapID CB Plus tests for

gram pos bacilli in 4 hrs

urease pink means

pos

elek plate tests for

toxin

visible precipitin lines on elek plate mean

toxin

bordetella pathogenic species

pertussis, parapertussis, bronchiseptica

bordetella infections

upper respiratory tract infections, pertussis

transmission of bordetella

droplets

bordetella virulence factors

fimbriae adhesion, tracheal cytotoxin, pertussis toxin

paralyzes moving cilia and prevents expulsion of organism by coughing and evading immune cells

tracheal cyto toxin

disrupts host cell function and inhibits recieving cell signalling and dna processing

pertussis toxin

b pertussis causes

whooping cough

stages of b pertussis whooping cough infection

catarrhal, paroxysmal, convalescent

catarrhal stage of whooping cough

flu like symptoms, mild cough runny nose for several weeks

paroxysmal stage of whooping cough

violent whooping cough, causes vomiting, resp distress, 1-4 weeks

convalescent stage whooping cough

asymptomatic, can transmit infection

b parapertussis infection

upper respiratory tract, less virulent and less common

b bronchipacia infection

respiratory illness in immunocompromised

bordetella specimen collection

nasoparyngeal swab

preliminary id of bordetella

direct fluorescent antibody stains

regan lowe agar is made of

charcoal agar with horseblood and cephalexin

regan lowe agar purpose

inhibit urt normal flora, grows bordetella

optimal growth media for bordetella

regan lowe or bordet gengou

A gram stain of a colony from the loeffler medium showed

pleomorphic gram positive rods. What media should the

organism besub- cultured to?

potassium tellurite

what is specimen of choice for culturing b pertussis

nasopharyngeal swab

Identify the organism

• Results

• Beta Hemolytic

• GPC

• Catalase: NEG

• Taxo A: Susceptible

• SXT: Resistant

group a strep

Lancefield Test detects which antigen compound

carbohydrate

Which feature is used initially in the work up a possible throat

pathogen

beta hemolysis

A pathogen in of acute rhinosinusitis is:

enterococcus spp

true or false The American Board of Medical Microbiology recommends that the culture of nasopharyngeal specimens to detect carriage of potential pathogens such as Neisseria meningitidis, S. pneumoniae, and H. influenzae is encouraged.

false

Nutritionally Variant Streptococci require what substance for growth:

vitamin b6

what organisms can cause acute pharyngitis

beta hemolytic strep group a and c

yeast cause of infection

immunosuppressed, overgrowth, medication

virus infection in urt

pharyngitis, laryngitis

viruses associated with pharyngitis and laryngitis

rhinovirus, adenovirus, influenza, parainfluenza, respiratory syncytial virus in children

acute pharyngitis is

strep throat

throat swabs are made of

calcium alginate

first swab in strep test is for

direct strep test in clinic

2nd swab in strep test is for

lab testing if s pyogenes is negative

limits to direct strep test

does not detect group c or g strep, low sensitivity and high specificity

after streaking strep culture,

stab media in streaked lines to enhance hemolysis

strep tests should be incubated

anaerobically increased co2

if no beta hemolysis on strep culture

report no pathogenic strep, reexamine in 48 hrs

if beta hemolytic colonies present on throat culture

gram stain to look for gram pos cocci, catalase test for negative, lancefield test for A C G, confirm with pyr and taxo a (susceptible)

patients with group a strep should be treated with

penicillin or amoxicillin

if penicillin allergy, treat strep a with

cephalosporin, clindamycin, clarithromycin, azithromycin

antimicrobial susceptibility testing is only done on beta hemolytic strep if

penicillin allergy

if beta hemolysis on strep culture

report strep

pyr test detects

pyrrolidonyl arylamidase

hydrolyzes substrate L pyrrolidonyl B napthylamide to end product naphthylamide, then it is detected with reagent nn dimethylaminocinnamaldehyde

pyr

pos pyr test

red color

pyr pos s pyrogenes is

strict pathogen

A urine culture Gram stain shows gram positive cocci in clusters. The

organism tests catalase positive. The MLS should perform a coagulase

test and:

a) Nitrocefin

b) Bacitracin

c) Novobiocin test

d) O/F test

novobiocin

The enterotoxin produced by hemolytic S. aureus, coagulase positive:

a) Destroyed by boiling at 100C for 30 mins

b) Identical to the TSS toxin

c) Causes food poisoning

d) Highly antigenic

food poisoning

The most critical distinction between S. aureus and other

Staphylococcus is:

a) DNAs production

b) Catalase production

c) Coagulase production

d) Hemolysis

coagulase

During the past month, S. epidermidis has been isolated from blood

cultures 2-3 times the rate from the previous year. The most logical

explanation for the increase is:

Blood culture media are contaminated with the organism

Hospital ventilation system is contaminated with the organism

Improper skin preparation before drawing the blood culture

Isolate is being spread person-to-person

improper skin prep

Identify the organism: catalase POS, slide coagulase: NEG, tube

coagulase: NEG, bacitracin: Susceptible, lysostaphin: resistant

a) S. aureus

b) S. saprophyticus; Novobiocin test required

c) Micrococcus spp.

d) Unable to determine

micrococcus

genetic recombination of 2 bacterial genomes is called

transduction

normal flora of skin

staph aureus and epidermis, corynebacteria, yeast (candida), micrococci, proprionibacterium

which structure contributes to antibiotic resistance

plasmid

which is a sterile anatomical site

lower respiratory tract

which of the following is a non sterile site

upper respiratory tract

tetanus

contact (cuts)

salmonella

food ingestion or fecal-oral

babesiosis

ticks/ flies/mosquitoes

black plague

ticks/ flies/ mosquitoes

tuberculosis

airborne/inhalation

syphilis

contact (intercourse)

contain only one set of chromosomes

haploid

double stranded, closed, circular, autonomously replicating extrachromosomal genetic elements

plasmid

pieces of DNA that move/exchange

genetic material between plasmids and the

chromosome. This action increases mutation

occurrences

transposons

a bacteria’s genome is

altered by the acquisition of foreign DNA from a

donor bacterial cell. The recipient bacteria will have a mixture of their

original DNA and the donors DNA

genetic recombination

when a bacteria dies, they lyse and their DNA

segments are released into the surrounding environment.

– A recipient bacterium absorbs the donors DNA segments and the

donor DNA combines with the recipients genome to form new

recombinant DNA.

transformation

A bacteriophage will integrate their DNA into a bacteria’s

chromosome.

» Viral replication occurs and viruses are formed in the

bacterium. Newly formed viruses are released through host cell

lysis which infect other bacteria.

» When the virion incorporates its own DNA into the bacteria,

the bacteria will contain or original host bacterium and/viral

recombinant DNA.

transduction