Bacteriology, Mycology, And A Little Virology For Microbiology Block Ii

Front 1

What does an outer membrane on bacterial cells do?

Back 1

this lipid membrane found on gram - cells prevents the passage of small molecules like antibiotics and bile salts, and allows the bacteria to survive treatment and the gut--> note that lipid enveloped viruses undergo respiratory transmission, while naked viruses are usually gut survivors, transmitted by the orofecal route

Front 2

What virus is the main cause of the common cold?

Back 2

Rhinovirus

Front 3

What 2 viruses are the main causes of the common cold?

Back 3

Rhinovirus > Coronaviruses

Front 4

What is coryza?

Back 4

nasal symptoms of the common cold

Front 5

Name a couple diseases caused by viruses that have incubation periods that last for months or more.

Back 5

AIDS
rabies

Front 6

About how long would the incubation period be for a systemic viral infection, such as measles or mumps?

Back 6

1-3 weeks

Front 7

What medication would you use to treat Herpes?

Back 7

acyclovir

Front 8

Can Herpes cause encephalitis?

Back 8

yes

Front 9

What is the virulance factor associated with Streptococcus pyogenes?

Back 9

M protein

Front 10

What are the encapsulated bacteria?

Back 10

"Some Killers Have Pretty Nice Capsules"

Front 11

What bacteria is responsible for Scarlet fever and what is its toxin that causes most of the symptoms?

Back 11

Streptococcus pyogenes

Scarlet fever = strep throat (local infection) complicated by systemic toxemia (inflammation) as a result of pyrogenic exotoxin

25% of Strep. pyogenes are lysogenized by phage that encodes pyogenic exotoxin

Front 12

What Penicillins have been modified to interact with gram - bacteria?

Back 12

Remember: all Penicilins end in "cilin"

"Ordinary Men Never Take 2nds":
Oxacillins (Cloxacilin, Dicloxacillin, Flucloxacillin) Methicillin, Nafcillin, Temocillin
-->all are part of 2nd group which means they are beta lactamase resistant

Penicillin V & G are used against gram +

All other Penicillins are noted for their use against gram - (particularly common are Ampicillin and Amoxicillin)

Front 13

Would you still be able to repress a represssible operon if the repressor gene were mutated and the reporessor protein inactivated?

Back 13

Yes, because all repressible operons are also under attenuation

Front 14

What family of viruses does RSV belong to?

Back 14

Paramyxo--they form synctia

Front 15

Patient presents with cough, coryza, conjunctivitis, and bluish gray spots on buccal mucosa. What does he have?

Back 15

Measles

the 4 Cs: cough, coryza, conjunctivitis, & Koplick spots

Front 16

What drug might you use against an Influenza flu, especially if you don't know whether it's type A or B?

Back 16

Neuraminidase inhibitors

Front 17

What is the most likely causative agent in a kid receiving Penicillin for an illness caused by beta-hemolytic bacteria?

Back 17

Streptococcus pyogenes

Front 18

What is the only membrane directed antibiotic that is specific for bacterial cells?

Back 18

Polymyxin

Front 19

If there is a mutation in the palindrome of the operator region of an inducible Operon, what will happen?

Back 19

The Operon, which would normally be repressed, would be active, since the repressor protein would not be able to bind to the operator.

Front 20

What 2 enteroviruses cause hand foot and mouth disease?

Back 20

Entero 71 and coxsackie A virus

Front 21

Are Haemophilus influenza capsulated or nonencapsulated?

Back 21

Both! Some have capsules and can travel further in the body that those that do not have capsules.

Front 22

What organism commonly causes infections in AIDS patients and might be treated with Fluconazole?

Back 22

Candida albicans

Front 23

What bacteria are acid fast?

Back 23

Mycobacteria, Nocardia, Rhodococcus

Front 24

What are you thinking when a pseudomembrane forms in the airways, obstructing airflow?

Back 24

the Strangling Angel of Death--Corynebacteria diphteria

local URT ix with systemic toxemia due to diptheria toxin (encoded by tox gene on phage genome)

preventable with DTap vaccine and Tdap booster

Front 25

What acid fast organism branches?

Back 25

Nocardia

Front 26

What are some characteristics of atypical pneumonia?

Back 26

it will be bronchial (not lobar)
little to no sputum

Front 27

What organism is responsible for an atypical pneumonia that can be diagnosed with a cold-agglutinin serum titer?

Back 27

Mycoplasma

Front 28

What's the causative agent in a poorly immunized individual now experiencing muscle spasms?

Back 28

Clostridium tetani -- tetanus

Front 29

Patient presents with difficuty seeing, swallowing, speaking. Later has weakness in upper extremities, spreading to respiratory tract.

Back 29

Patient has symmetric descending flaccid paralysis, a symptom of food borne botulism--> caused by consumption of the botulinum neurotoxin formed by Clostridium botulinum

Front 30

IV drug abuser with wound--experiences flaccid paralysis around site of wound that is spreading away from it

Back 30

Wound botulism caused by wound contamination with the spores of Clostridium botulinum

Front 31

Infant ate honey; now can't suck, can't poop, is weak and has CN deficits. What caused this?

Back 31

kid ingested Clostridium botulinum spores which grew and produced neurotoxin in kid's intestines.

Front 32

What vaccine is particularly important for college freshmen and what does it prevent?

Back 32

Meningococcal vaccine

prevents meningitis

Front 33

What type of hemolysis shows a zone of greening and what organism/s is it associated with?

Back 33

alpha hemolysis

caused only by normal flora streptococci
exception: S. penumoniae can be normal flora or a serious pathogen

Front 34

What type of hemolysis shows a zone of clearing and what organism would you particularly associate it with?

Back 34

beta hemolysis

bacteria with cytolytic toxins, especially Strep. pyogenes

Front 35

What type of hemolysis do GAS, GBS, and GDS show? What is the prototypical species for each of these?

Back 35

beta

GAS = S. pyogenes
GBS = S. agalactiae
GDS = Enterococcus spp

Front 36

Name a gram + diplococcus

Back 36

Strep. pneumoniae

Front 37

What is the significance of Streptococcal spp being catalase negative?

Back 37

They lack the enzyme to detoxify H2O2 and are thus anaerobes. Catalse test is used to distinguish Staph. from Strep.

Front 38

What is the major cause of neonatal meningitis?

Back 38

GBS (Strep. agalactiae) from the maternal vaginal canal

Front 39

What beta hemolytic species is never considered normal flora?

Back 39

Streptococcus pyogenes

Front 40

What is the ajor virulance factor of GAS (S. pyogenes) and how does it work?

Back 40

M protein

more than 60 serotypes
functions like a capsule to inhibit complement fixation and phagocytosis

Front 41

What 2 exotoxins does GAS possess that provide a cloud of cytotoxins (that kills WBCs) around the site of infection?

Back 41

Streptolysin O (oxygen labile--> active only in anaerobic conditions)

Streptolyisn S (think "S for oxygen Stable")

Front 42

What is Spe and who produces it?

Back 42

Spe = pyrogenic exotoxin made by GAS (S. pyogenes) that are lysogenized by certain phages

Spe are inflammatory superantigens

Front 43

Person with flushed cheeks and strawberry tongue. Rash spreads to extremities, trunk and causes desquamation. What's going on?

Back 43

strep throat (GAS/S. pyogenes) complicated by pyrogenic exotoxin (Spe) b/c this particular GAS happens to be lysogenized

Front 44

Person comes in with erythematous skin lesions, subcutanous nodules, and joint pain. What should you look for in history?

Back 44

a sore throat (pharyngitis) 2-3 weeks earlier--pt probably had GAS infection and now has Acute Rheumatic Fever

Need to watch heart valves

Front 45

Pt with acute glomerulonephritis mentions that they had a skin infection a few weeks earlier. Cause?

Back 45

probably GAS--S. pyogenes infections in the pharynx or the skin can be complicated by hypersensitivity reactions and lead to AGN

Must perform serology to lab to detect anti-streptolysin O (ASO) or other

Front 46

How do you treat a Streptococcus pyogenes infection?

Back 46

Penicillin--nearly all strains are sensitive

Front 47

Should you freak out if you find pleomorphic, club-shaped rods forming "Chinese characters" (V or L shapes) in someone's URT?

Back 47

Not necessarily.
Corynebacterium diphteriae are only pathogenic if they are lysogenized with a phage containing the tox gene for Diphtheria toxin

Front 48

These normal flora of the mouth are known to invade the bloodstream and cause endocarditis:

Back 48

HACEK group
H= Haemophilus influenzae
A = aggregati bacteria
C = Cardiobacterium hominis
E = Eikenella corrodeus
K = Kingella

Front 49

Moraxella catarrhalis, of the genus Neisseria, causes waht dieseases?

Back 49

otitis media in kids
chronic bronchitis in adults

dz is similar to thsoe caused by unencapsulated H. influenzae

Front 50

D factor and V factor are blood-derived products that are components of enriched chocolate agar. What grows in this special media?

Back 50

Haemophilus influenzae

It will not grow on blood agar!

Front 51

Why must gram stains be performed on samples from sterile sits but antigen detection assays do not?

Back 51

Sterile sites don't contain normal flora. We detect specifically those antigens on pathogenic organisms.

Front 52

What is Hib?

Back 52

a vaccine against the type b capsule of Haemophilus influenzae

composed of purified type b capsular polysaccharide conjugated to protein

the capsule of H. influenzae is its major virulance factor, though there are many different types and not all strains have one at all (they are non-encapsulated and thus non-typable)

Front 53

What normal bacteria of the nasopharynx can spread locally to cause the following invasive infections?
epiglottitis
cellulitis
pneumonia

Back 53

H. influenzae

this is now uncommon since most such infections were caused by type b strains and most people are protected due to the Hib vaccine

Front 54

What infections are nontypable strains of H. influenzae known for causing?

Back 54

Surface infections:
otitis media (2nd to S. penumoniae)
Sinusitis
Cunjunctivitis (pink eye)
Chronic bronchitis, pneumonia (in debilitated adults)

Front 55

30-yo breaks his nose. Several weeks later says he feels sick, collapses, and is taken to ED with high fever. What's going on?

Back 55

sinus trauma allowed nontypable Haemophilus influenzae to invade CNS and cause meningitis

Front 56

Bacteria with cholesterol in its membrane and no cell wall

Back 56

mycoplasma

Front 57

What bacteria will only grow slowly on special media enriched in sterols (i.e. cholesterol) and finally produces fried-egg colonies?

Back 57

mycoplasma

Front 58

22 yo comes in with walking case of bronchopneumonia. You get no growth on routine media. Likely agent? Treatment

Back 58

mycoplasma
Treat with erythromycin (targets 50S ribsosomal subunit)

this atypical bacterium (no cell wall) causes atypical (walking) pneumonia and can't be treated with antibiotics that target the cell wall

Front 59

What is the number one cause of Community acquired pneumonia?

Back 59

Strep. pneumoniae

Front 60

an organism that buds and branches

Back 60

Candida albicans--has both yeast and mold (hyphal) forms

Front 61

white patches on a newborn kid's throat

Back 61

thrush caused by candida albicans

Front 62

person with thickened, discolored fingernails and itchy rash in skin folds

Back 62

C. albicans infection

Front 63

person with lesions around mouth that are mildly disfiguring and unresponsive to medications

Back 63

Chronic Mucocutanous Candidiasis--genetically weakened immunity to Candida

Front 64

diabetic patient with urinary catheter begins to experience urgency and hematuria. what organism might you find and what's going on?

Back 64

Candida albicans ascended to kidney, causing cstitis/pyelonephritis

Front 65

A member of what genus causes whooping cough?

Back 65

Bordatella genus

(Bordatella pertussis)

Front 66

What are agglutinogens, pertactin, PT and fimbrial hemagluttinin (F-HA)?

Back 66

components of the acellular pertussis vaccine

(PT = pertussin toxin)

Front 67

What toxin causes increased levels of intracellular cAMP to inhibit monocyte and neutrophil activation/killing?

Back 67

Pertussis toxin, an adenylate cyclase (of Bordatella pertussis)

Front 68

What are the stages of pertussis?

Back 68

Catarrhal (mild sx but highly infectious)
Paroxysmal (whoping cough but decreasing communicability)

Front 69

What is Tdap?

Back 69

a booster given ppl 11-64 yrs of age, mainly for tetanus but also for diphtheria and pertussis

Front 70

What might be causing ciliary paralysis in a kid with a loud, barking cough?

Back 70

tracheal cytotoxin realeased from Bordatella pertussis

Front 71

Stenotophomonas maltophilia and Burkholderia cepacia often cause what and in whom? What other organism also causes this?

Back 71

LRT (often pneumonia) in cystic fibrosis patients

Pseudomonas aeruginosa is the most common culprit

Front 72

A teenager has a jetski accident on a lake and cuts his foot badly. Later, the wound is infected. What is the likely organism?

Back 72

Aeromonas hydophila

Front 73

A wounded soldier in Iraq gets an infection in her wound. What is the likely cause?

Back 73

Acinetobacter baumannii, found in soil and water

likely resistant to antibiotics

Front 74

Unusal gram - organisms should be expected to display the following traits:

Back 74

affect compromised hosts (inlcuding those who have wounds)
be transmitted from the environment (soil, water, hospital, etc.)
be resistant to antibiotics

Front 75

CF patient with pneumonia--what's the cause? What's the capsule?

Back 75

Pseudomonas aeruginosa that has switched phenotypes from a slime layer capsule to a mucoid capsule.

Front 76

What is elastase?

Back 76

One of Pseudomonas aeruginosa's arsenal of exotoxins. It shifts the balance of proteolytic and anti-proteolytic enzmes in the lung to cause direct damage to lung tissue and vessels.

Front 77

wound oozing gren pus

Back 77

infected with Pseudomonas aeruginosa whose pigments lend the green color

Front 78

kid with swimmer's ear (acute otitis externa)

Back 78

dermatitis of the ear canal and skin caused by Pseudomonas aeruginosa

Front 79

How would you treat a CF patient with copious sputum production as a result of pneumonia?

Back 79

Pseudomonas aeruginosa is notoriously resistant to antibiotics and the mucoid capsules protect the organism further. USe combination (2 drug) therapy including quinalones (that target nucleic acid replication)

Front 80

What is the only atypical bacteria that can cause hospital acquired pneumonia?

Back 80

Legionella (usu. pneumophila)--> while most Legionella ix are caused by serogroup 1, nosocomial ix can be caused by others

"pneumo" (lung) + "phila" (love) = loves lungs

Front 81

Where do Legionella grow?

Back 81

in protozoa (amoebas) in water and in macrophages within the human body

Front 82

What can you get from a cooling tower?

Back 82

Legionnaire's Dz (acute pneumonia) or Pontiac fever (mild form) caused by Legionella

Front 83

Pt with cough, fever, feels kind of lous. CXR shows pneumonia. Normal labs are negative and there's no growth on traditional media. Penicillin doesn't help.

Back 83

Legionella

Front 84

Pt with a Penicillin resistant, atypical pneumonia that won't grow on traditional agar has negative results with most labs. Urine antigen test for Legionella also negative. What's he got?

Back 84

Probably still Legionella. Urine antigen tests only detect serotype 1, which is the most common.

Front 85

Patient gets an atypical pneumonia from non-serotype 1 Legionella. What do you do?

Back 85

Treat patient with macrolides (b/c Legionella resistant to Penicillin)

Monitor and disinfect water reservoirs in hospital b/c non serotype-1 Legionella is probably nosocomial and Legionella is transmitted through contaminated water

Front 86

What atypical mycobacteria cause pulmonary diseases in AIDS patients?

Back 86

Mycobacterium avium/intracellulare

Mycobacterium kansasii

Front 87

AIDS patient with respiratory disease and brain abscess. agent?

Back 87

Nocardia spp

Front 88

AIDS patient with lung disease caused by acid fast bacteria. PPD and IFN gamma release assays are negative. Agent?

Back 88

Might still be Mycobacterium b/c AIDS px often give false negatives. But a related acid fast pathogen is Rhodococcus.

Front 89

Mycoplasma and Mycobacterium both have unusual structural characteristis. What are they and what diseases do these organisms cause?

Back 89

Mycoplasma have no cell wall. Causes respiratory dz of varying degrees of severity (including atypical pneumonia) but is never invasive.

Mycobacteria are acid fast. Causes TB and leprosy.

Front 90

What are mycolic acids and what genus possesses them?

Back 90

cell wall outer glycolipids that confer a waxy quality to mycobacterium, rendering them acid fast

Front 91

What was 'Sharepoint Server 2001' and how is it different from the current iteration of Sharepoint?

Back 91

Document management and enterprise search based on MS Exchange. The current iteration is based on .NET and SQL server.

Front 92

TB patient gets meningitis and dies. What happened?

Back 92

Miliary (extrapulmonary) TB = complication where mycobacteria sprads via bloodstream to distant organs ncluding meninges

Front 93

BCG vaccine

Back 93

live attenduated strain of Mycobacteria bovis for prevention of the related TB

Front 94

MVA85A

Back 94

new TB vaccine in trials

recombinant vaccinia virus expressing antigen 85A from Mycobacterium tuberculosis

Front 95

What causes meningitis, pneumonia, and otitis media?

Back 95

"Pneumococcus is to Parents what group B strep is to Babies"

GBS causes meningitis and pneumonia in neonates

Strep. pneumoniae causes meningitis and pneumonia in adults. It also causes otitis media in kids.

Front 96

most common cause of otitis media?

Back 96

Strep. pneumoniae/pneumococcus

Front 97

Major cause of both nosocomial and hospital acquired pneumonia. Heavy consolidation on CXR with copious "rusty" sputum?

Back 97

Strep. pneumoniae / pneumococcus

Front 98

How do you treat pneumococcal pneumonia?

Back 98

Usually Penicillin

should be prevented with a conjugate vaccine (or with the originial PPV 23 vaccine)

Front 99

What vaccination against pneumococcus should you give to a 4 month old child?

Back 99

PCV-13 (replaced PCV-7)

purified capsule polysaccharides of the 13 most common serotypes conjugated to protein

PPV (Pneumovax 23) is only given to adults

Front 100

pt with meningitis. organism visualized by INdia Ink

Back 100

cryptococcus

Front 101

Immunosuprressed diabetics in ketoacidosis are susceptible to what mycosis?

Back 101

zygomycosis