Clinical Micro - Rtis

Front 1

_ abscesses occur in children less than 5 years old, while
_ abscesses occur in children older than 5 years old.

Back 1

Peri/retrotonsillar abscess

Retropharyngeal/Lateral abscess

Front 2

Pediatric patient complains of difficulty swallowing and a change in phonation. X ray of the neck shows widening of space between cervical spine and post pharyngeal wall. What is most likely dx?

Back 2

Retropharyngeal/Lateral abscess d/t group A streptococcus

Front 3

Middle Respiratory Tract infections except for _ are caused by viruses.

Main symptom of MRTI’s is _

Back 3

Epiglottitis (usu dt H flu or S pneumonia)

inspiratory stridor.

Front 4

_ : Symptoms include Inspiratory Stridor, throat and neck pain, fever. It is most commonly due to bacteria, usually H. flu or S. pneumonia.

Back 4

Epiglottitis

Front 5

When a patient has a "harsh barking cough" that can be described as "brassy", what do they most likely have?

Back 5

Laryngitis/Croup.

D/T Parainfluenza

Front 6

Croup is most commonly caused by _

Back 6

parainfluenza virus

Front 7

Bubbling rhonci is typically a symptom of what condition?

Back 7

Bronchitis

Front 8

T/F a true sputum sample will contain lots of inflammatory cells and select squamous epithelial cells

Back 8

False. It should contain NO squamous epithelial cells

Front 9

2/3 of Community Acquired Pneumonia are caused by _

Back 9

Streptococcus Pneumonia

Front 10

What are major Anaerobic bacteria?

Back 10

Actinomyces, Bacterioides, Clostridium

ABC

Front 11

What are the 2 spore forming bacteria?

Back 11

Bacillus and Clostridium

Front 12

Catalase + bacteria are _. What test is performed after this?

Back 12

staphylococcus

Coagulase to determine if it is Staph Aureus (+)

Front 13

Catalase (-) bacteria are _.

After this, you can look at hemolytic properties of the bacteria. Alpha hemolysis is most likely _, Beta hemolysis is _

Back 13

Streptococcus

S. Pneumoniae (Optochin sensitive) or Viridans (Oprtochine resistant)

S pyogenes (Group A), or S agalactiae (Group B)....determine with an A disc

Front 14

Streptococcus Pyogenes commonly causes _.
It is a Gram _ that grows _ catalase _, _ hemolysis, and _ sensitive

Back 14

Strep Throat

(+) cocci, in chains,

(-), ϐ, bacitracin sensitive (type A).

Front 15

_ : Gram (+) cocci that grows in chains, catalase (-), ϐ hemolysis, and bacitracin sensitive (type A).

Back 15

Streptococcus Pyogenes

Front 16

The essential virulent factor of Streptococcus Pyogenes is _. What does this do?

Back 16

M protein which degrades C3b to escape phagocytosis.

*It is M protein that we use for serotyping, no the capsule (bc the capsule contains hyaluronic acid similar to self cells)

Front 17

Virulence factors for streptococcus pyogenes include M Protein, Protein G, and Protein F.

What do all these do?

Back 17

M protein which degrades C3b to escape phagocytosis.

Protein G also inhibits phagocytosis by binding to Fc portion on antibodies. Protein F mediates attachment,

Front 18

What is the tx for Streptococcus Pyogenes infections? (Strep throat)

Back 18

Penicillin or Erythromycin/1st generation cephalosporin.

Front 19

Scarlet fever is a complication that can arise from _.

Pt has what classic symptoms?

Back 19

Strep Pyogenes : specifically streptococcal pyrogenic exotoxins (SPE’s). These exotoxins are superantigens, thus causing polyclonal T cell activation and uncontrolled cytokine release.

The patient has a fever, sand paper rash, ‘strawberry tongue’

Front 20

Patient complains of a sand paper rash, upon P/E you note that the tongue is beefy red with large papules on it. What is the likely dx, and how does this arise?

Back 20

Scarlet fever.

This condition arises when S Pyogenes becomes infected with a bacteriophage.

Front 21

Necrotizing fascitis is caused by _.

If you were to perform lab tests on this organism, what would the results be? (ie. Gram stain, catalase, hemolysis, bacitracin)

Back 21

Streptococcus Pyogenes

Gram (+) cocci that grows in chains, catalase (-), ϐ hemolysis, and bacitracin sensitive (type A).

Front 22

Acute Glomerulonephritis is a complication that can arise from what type of bacteria?

What type of hypersensitivity reaction is this?

Back 22

Group A Strep (Strep Pyogenes)

Type III hypersensitivity

Front 23

Rheumatic Fever is a type _ hypersensitivity reaction, and can arise roughly 3 weeks post _ infection and results in damage to _

Back 23

Type II hypersensitivity
Group A Streptococcus (strep pyogenes)
mitral and aortic valves

Front 24

S Pneumonia is a gram _, with a _ , _ hemolysis, (-/+) Bile solubility test, and optochin (sensitive/resistant)

Back 24

+ diplococcus
thick capsule,
alpha
(+) Bile
sensitive

Front 25

What gram stain does S pneumonia have?

Back 25

gram + diplococcus

Front 26

Streptococcus pneumonia has what type of hemolysis?

Back 26

alpha.

Front 27

T/F Streptococcus Pneumonia is a normal flora in URT

Back 27

true.

but can lead to pathology due to alcohol, narcotic use, TRI, heart/lung disease, diabetes (pretty much any one who is immunocompromised).

Front 28

What is it about S Pneumonia that helps them avoid phagocytosis?

Back 28

They have a very thick polysaccharide capsule.

The alveoli become filled with inflammatory exudates causing the symptoms

Front 29

Alcoholic who has pneumonia…what are the two most likely pathogens? And how do you tell the difference?

Back 29

Strep Pneumonia or Klebsiella.

Difference? Strep pneumonia will have a rust colored sputum. Klepsiella he will have red, gelantinous sputum.

Front 30

Runny nose, congestion, cough, fever with shaking chills, chest pain, purulent, rust colored sputum, shallow/rapid breathing......these are symptoms of what infection?

Back 30

Strep. Pneumonia

Note the purulent, RUST colored sputum, fever with shaking chills

Front 31

Cornyebacterium Diphtheria is unique because of what appearance of the colonies? It is a gram _, and selective for _ agar

Back 31

chinese letter colonies
gram + rod,

tinsdale agar ( can also be Loeffler’s serum or Potassium tellurite)

Front 32

What gram + rod is selective for tinsdale agar?

Back 32

C Diptheria

Front 33

When grown on postassium tellurite, C Diptheriae appears _due to _

Back 33

black
tellurite reductase

Front 34

What species is the primary reservoir for C Diptheria?

Back 34

Humans.

Front 35

What is the main cause of pathology in a C diphtheria infection?

(Include substance as well as biocohemistry)

Back 35

AB toxin. It goes into cells via endocytosis, an active component is released causing ADP ribosylaton of G protein which will inhibit elongation factor 2 (EF2), preventing protein synthesis and leading to cell death.

Front 36

The characteristic symptoms of C diphtheria infection is _

Back 36

grayish white membrane on tonsils.

Front 37

Pt presents with sore throat, low fever, and fatigue. PE shows a grayish white membrane on tonsils, and culture shows a gram + rod selective for tinsdale agar. How do you treat this patient?

Back 37

First of all, know that this is a Clostridium Diphtheria infection.

Treat with Antitoxin. Antibiotics will inhibit transmission but will not affect the toxin.

Front 38

Pt presents with sore throat, low fever, and fatigue. PE shows a grayish white membrane on tonsils, and culture shows a gram + rod selective for tinsdale agar. How could this infection have been avoided?

Back 38

DPT vaccine (diphtheria toxoid)

Front 39

_ Growth requires factor V (NAD) and factor X (heme).

Back 39

Haemophilus Influenza

Front 40

_ will Grow on Chocolate agar, not blood agar

Back 40

Haemophilus Influenza

Front 41

_ Causes pneumonia, epiglottitis (ages 2-5), meningitis (under 2

Back 41

Haemophilus influenza

Front 42

Haemophilus influenza causes _, _ in children 2-5, and _ in children under 2.

Back 42

Pneumonia

Epiglottitis (2-5)

Meningitis (under 2)

Front 43

The major virulent factor on for Harmophilus influenza is _

Back 43

Type B capsule is a polymer called PRP (polyribitol phosphate). It inhibits opsonization and phagocytosis.

In this organism, it is the endotoxin that is locally toxic, it has no exotoxins!

Front 44

Pt complains of fever, ST, hoarseness, SOB. No growth on blood agar. Culture on chocolate agar shows a gram (-) coccobacilli. How do you treat this individual?

Back 44

First of all, know that this is a Haemophilus Influenza infection.

Treat with a 3rd generation cephalosporin.

Front 45

Legionella Pneumophila causes _. What is it's gram stain?

Back 45

Causes Legionnaires’ Disease

Rod Shaped, gram (-) bacteria, stains poorly using gram stain, so use Silver staining or DFA.

Front 46

You should isolate Legionella Pneumophila using _ agar.

Back 46

BCYE (buffered charcoal yeast extract agar due to it’s special requirement of L-cysteine, ferric ions, and slightly acidic conditions.

Front 47

(T/F) Porin Proteins and the surface protein Mip on L pneumophila prevent phagocytosis by macrophages.

Back 47

False.

This organism likes to get into macrophages. These two substances will AID in phagocytosis, and once inside the organism will replicate and create small lung abscesses.

Front 48

25% of cases infected with _ have abdominal symptoms including pain, diarrhea and vomiting.

Back 48

L pneumophila

Front 49

(T/F) Te most rapid and accurate way to diagnose L Pneumophila is DFA.

Back 49

False. Direct Fluorescent Antibody (DFA) is most rapid method, but misses a lot of positive cases. You should also Culture on BCYE agar.

Front 50

Patient complains of dry cough, headache, muscle aches, abdominal pain and diarrhea. Culture reveals a gram - bacilli that grows best on BCYE agar. How was this organism likely transmitted?

Back 50

It is describing L Pneumophila.

It is transmitted by breathing aerosolized water

Front 51

Patient complains of dry cough, headache, muscle aches, abdominal pain and diarrhea. Culture reveals a gram - bacilli that grows best on BCYE agar. How do you treat this patient?

Back 51

It is describing L pneumophila.

Treat with Erythromycin alone, or in combination with rifampin.
*Does not respond to Beta lactams bc it produces beta lactamase

Front 52

Culture in BCYE and DFA is the most reliable way to diagnose what type of infection?

Back 52

L Pneumophila

Front 53

Bordetella Pertussis Causes _
It is a Gram _. It is strictly _ and strictly _

Back 53

Whooping Cough.
(-) rod,

encapsulated and strictly aerobic.

Front 54

There are 3 toxins that are virulent in Bortella Pertussis. The most virulent _, causes toxicity by _

Back 54

Pertussis toxin
ADP ribosylates a G inhibitory protein that affects adenylate cyclase and increases cAMP levels. cAMP leads to a big increase in mucus secretion.

Front 55

Regarding Bordetella Pertussis (and it's 3 virulent toxins)...
Adenylate toxin does what?
Tracheal cytotoxin produces _ causing _

Back 55

Adenylate toxin increases cAMP levels by catalyzing ATP to cAMP. cAMP leads to a big increase in mucus secretion.

tracheal cytotoxin produces NO causing the death of ciliated cells. No ciliated cells mean the only way to remove foreign material is to cough persistently.

Front 56

The course of whooping cough is broken into three stages, what are they?

Back 56

Catarrhal ( profuse and mucoid rhinorrhea)

Paroxysmal (COUGHING, INSPIRATORY WHOOP)

Convalescent - gradually resides

Front 57

What organism has a characteristic "mercury drop" appearance on charcoal enriched blood (chocolate) agar?

Back 57

Bordetella Pertussis

Front 58

Klebsiella pneumoniae is a gram _. The colony appears _ d/t it's _

Back 58

Gram - Rod

Mucoid dt it's large polysaccharide capsule.

Front 59

Pt complains of fever, chills, chest pain and productive cough with red gelatinous sputum. What would you suspect the colony to look like on MacConkey agar?

Back 59

Klebsiella Pneumonia - It is a gram - rod that is a lactose fermenter, so you would see PINK colonies on macconkey agar.

Front 60

What is the major virulent factor in Kelsiella pneumoniae infections?

Back 60

It's capsule, it interferes with phagocytosis, and forms lung abscesses which may metastasize to distant organs

Front 61

The characteristic sputum in Klebsiella infections is _

Back 61

Red, Gelatinous Sputum

Front 62

Why is Klebsiella pneumoniae resistant to antimicrobials?

Back 62

They acquire and are a source of R factors, which contain transposons responsible for making resistance genes.

Front 63

Pt complains of fever, chills, chest pain and productive cough with red gelatinous sputum. How do you treat them?

Back 63

-Describing Klebsiella pneumonia.

Ciprofloxacin or a combination of cephalopsporins. (resistant to antimicrobials dt R factor)

Front 64

Pseudomonas aeruginosa is a Gram _ . What is unique about this colony is that it _

Back 64

(-), non spore forming rod

Produces colorful water–soluble pigments which discolor the culture medium (usually bright green due to the combination of a yellow and blue pigment).

Front 65

Pseudomonas aeruginosa is relatively resistant to antibiotics due to it's _

Back 65

LPS and porin proteins on the outer membrane

Front 66

_ establishes infection where there is a break in the first line of defense. After attaching to the epithelial glycolipid it secretes Exotoxin A, Exoenzyme S, and Elastase into the host cells.

Back 66

Pseudomonas aeruginosa

Front 67

_ released by Pseudomonas aeruginosa inactivates EF-2 by ADP ribosylation (just like diphtheria)

Back 67

Exotoxin A

There is no systemic effeects but it is cytotoxic and locally destructive.

Front 68

Exoenzyme S released by Pseudomonas aeruginosa does what?

Back 68

ADP ribosylates several intracellular proteins including the cytoskeleton filament vimentin, thereby DESTROYING THE cells CYTOSKELETON. It may also function as a surface bound adhesion.

Front 69

Pseudomonas aeruginosa is _ hemolytic, oxidase _, and what is characteristic about this colony?

Back 69

beta hemolytic, oxidase positive,

It produces procyanin (green), and has a fruity odor!

Front 70

How would you treat a pseudomonas aeruginosa infection?

Back 70

Anti-pseudomonal penicillins such as carbenillin and piperacillin

Front 71

Mycobacterium Tuberculosis is a _, _ shaped bacterium. It is unique because it's cell wall contains _

Back 71

acid fast (red), rod shaped.

Contains LAM (similar to LPS), and N glycolyl muramic acid, rather than Nacetylmuramic acid.

Front 72

Mycobacterium Tuberculosis contain _ in their cell envelope which inhibit _.

Back 72

Sulfatides inhibit phagosome-lysosome fusion allowing for intracellular survival

Front 73

Most of the damage done in M tuberculosis infections is done by _

Back 73

the host's immune system not by any endo/exo toxins released.

Tuberculin and mycolic acid (surface proteins) lead to delayed hypersensitivity

Front 74

A classic finding in M tuberculosis infections is _, which frequently breaks down into _ lesions and heal by _

Back 74

Ghon's complex (neutrophils,lymphocytes, mononuclear cells form a tubercle),
Break down into Necrotic caseous lesions
Heal by calcification

Front 75

You should screen suspected Mycobactium tuberculosis sputum using _ stain. If positive, it will fluoresce a _ . Positives from this should be confirmed via _, or _

Back 75

auramine rhodamine

bright, apple green

Ziehl Neelsen (AFB) or QFT-G (TB Gold)

Front 76

How do you treat Mycoplasma Tuberculosis?

Back 76

6-9 mo of combined antibiotics!
INH (can cause peripheral neuropathy)
Ethambutol (eye complications)
Rifampin (orange urine)
Pyrazinammide (hepatitis)
Streptomycin (autotoxicity)

Front 77

Mycoplasma Tuberculosis treatment involves 6-9 months of antibiotics. As such, side effects are quite common. What are the side effects of the following drugs?
INH.Isoniazid _
Ethambutol_
Rifampin _
Streptomycin _
Pyrazinammide _

Back 77

Peripheral Neuropathy
Eye complication
Orange Urine
Autotoxicity
Purazinammide

Front 78

_ is ppd negative, occurs in AIDS patients, and symptoms include weight loss, chills, night sweats. How do you treat this?

Back 78

M. Avium Intracellulare Complex (MAC)

treat with MACrolide

Front 79

Mycoplasma pneumoniae has a _ morphology.

Back 79

Fried egg appearance, or "mulberry shaped"

Front 80

How does Mycoplasma pneumoniae cause pathology?

Back 80

By destroying epithelial cells undergo desquamation and trigger an inflammatory response.

Front 81

Patient complains of fever, headache, malaise, ST, unproductive cough, chest pain, and earache. CXR shows bilateral interstitial pneumonia involving the hilar region and the basal area. What is the dx?

Back 81

Suspected Mycoplasma pneumoniae, but confirm via serology.

Front 82

What is the treatment for mycoplasma pneumoniae ?

Back 82

Erythromycin and tetracycline are usually used.

Beta lactams are ineffective because it doesn't have cell wall.

Front 83

Chlamydia pneumonia may have a role in what other condition?

Back 83

atherosclerosis

Front 84

The infected form of Chlamydia Pneumonia is called the _ , Intracellularly, it is called the _

Back 84

elementary body

reticulate body.

Front 85

Atherosclerosis associated with what pathogen?

Back 85

Chlamydia Pneumonia

Front 86

Bacillus anthracis are gram _, catalase _ .

Histologically, how do they look?

Back 86

+ rods, catalase +.

Form very long chains of rods with characteristic squared ends. On blood afar, they form a medusa head appearance

Front 87

What is unique about Bacillus Anthracis?

Back 87

All bacterial capsules are polysaccharide, except this one has a polyD glutamic (protein) capsule

Front 88

Virulence of Bacillus Anthracis is due to _ and _

Back 88

poly D glutamyl capsule (pXO2 plasmid is transduced),

and the antrax toxin (pxO1).

Front 89

The anthrax toxin contains (#) factors. What are they?

Back 89

3. 2 Active and 1 Binding
Edema Factor (A)
Binding Factor (B)
Lethal Factor (A)

(Similar to pertussis in that it has active and binding components)

Front 90

One way to distinguish B anthracis from other bacillus sp is _

Back 90

growing on regular medium then drop gamma phage. A clear area is + for B anthracis

Front 91

Bacillis cereus causes _

Back 91

food poisoning

Front 92

_ Causes Pneumonic Plague

Back 92

Yersinia Pestis

Front 93

Yersinia Pestis is a gram _ bacteria.

Under wayson staining it has a _ appearance

Back 93

(-)

safety pin appearance

Front 94

What organism produces fibrinolysin and phospholipase inside a flea, eventually blocking the gut. Sensing starvation, the flea begins feeding and eventually regurgitates into the bite wound...transmiting the organism into the human.

Back 94

Yersinia Pestis....causes the pneumonic plague!

Front 95

_ is the major virulent factor of Yersinia. What does it cause problems?

Back 95

Yop. (others are F1 capsular protein and PA1)
It inhibits phagocytosis by altering cytoskeletal organization of phagocytes. It also impairs production of inflammatory cytokines and chemokines, as well as inhibits platelet aggregation.

Front 96

_ is the drug of choice in treating the pneumonic plague

Back 96

Streptomycin

(Caused by yersinia)

Front 97

Nocardia Asteroides is associated with _, while Nocardia Brasiliensis is associated with _

Back 97

brain abscesses

skin infections

Front 98

Nocardia sp are gram _, and weakly _

Colonies may have the smell of _

Back 98

+ rods,

weakly acid fast

wet dirt

Front 99

All RNA virus are ss except _. All DNA viruses are ds except _

Back 99

reovirus

parvovirus.

Front 100

Rhinovirus is a member of the _ family, which are non enveloped, _stranded _NA, and (positive/negative) sense.

it causes _

Back 100

picorna,
single , RNA

positive

30-50% of common cold cases

Front 101

Rhinovirus attaches to respiratory epithelium via _.
What is the general pathogenesis behind this virus?

Back 101

ICAM - 1
The virus multiplies within the cell, gets released, and infects adjacent cells. The infected cells lose their ciliary motion and slough off, this injury causes release of inflammatory mediators

Front 102

What is the antiviral that is currently being trialed against Rhinovirus? How does it work?

Back 102

Pleconaril

Prevents uncoating of the virus (inhibits the release of the RNA)

Front 103

Adenovirus Causes _ It is a (non/enveloped) virus with _NA.

It spreads mostly via _

Back 103

Adenoviral pharyngitis.

non enveloped virus with ds DNA.

Respiratory droplets

Front 104

The unique symptoms of adenovirus infections (in comparison to the common cold) include _

Back 104

enlarged cervical lymph nodes, ST and pink eye (pharyngoconjunctival fever), acute hemorrhagic cystitis

Front 105

A vaccine against adenovirus is given in the military, containing (alive/killed) virus of serotypes _, _ and _. What is unique about this vaccine?

Back 105

live
4,7,21. It is administered orally.

Front 106

Coronavirus most famously causes _. Symptoms of this are _

Back 106

Sars (Type III coronavirus)

"Flu like symptoms" + diarrhea

Front 107

Antigenic Drift is a (small/large) mutation, and responsible for _

Back 107

(small, point mutation, small difference)

responsible for Epidemic

Front 108

Antigenic Shift is a (small/large) mutation, and responsible for _

Back 108

Large (big difference)

responsible for Pandemic

Front 109

Patients infected with Influenza virus are susceptible to developing secondary infections by what bacteria? (4)

Back 109

Staph aureus, Strep pyogenes, H influenza, or Strep Pneumonia.

Front 110

What vaccines are killed?

Back 110

(rest in peace always – rabies, influenza, polio, hepatitis A),

Front 111

The influenza vaccine is made from _ strains of influenza A, and _ strains of influenza B

Back 111

2 strains of influenza A, and 1 strain of influenza B

Front 112

_ such as _are effective against both type A and type B influenza virus

Back 112

Neuraminidase inhibitors such as Oseltamivir (oral tamiflu)

They act by blocking the enzymatically active neuramindase glycoprotein, thus limiting viral release from infected cells.

Front 113

Croup is caused by _ virus, and is characterized by what symptom?

Back 113

Paramyxovirus

Labored noisy breathing (stridor), with spasmodic and brassy cough.

Front 114

RSV is a _ stranded (+/-) _NA.

It belongs to the _ family

Back 114

Single stranded - RNA

Paramyxovirus

Front 115

_ and _ viridae contain Hemaglutunin and neuraminidase, while _ virus does not.

Back 115

Influenza and Parainfluenza

RSV does not (it contains G protein and F protein)

Front 116

The most common cause of cough, SOB, wheezing in an infant during mid winter is _

Back 116

RSV

Front 117

A monoclonal antibody called _is used to prevent RSV in immunocompromised individuals (with underlying illness).

Back 117

palivizumab

Front 118

Sin Nombre causes _.
Lab results should _, _, and a _ platelet count

Back 118

Hantavirus pulmonary syndrome

atypical lymphocytes, bandemia (left shift on WBC), and Low platelet count

Front 119

_ , is an AIDS defining infection.

Back 119

pneumocystosis or P. carinii pneumonia

Front 120

P carinii is inhaled and attaches to _ cells in the alveolar walls

Back 120

type 2 pneumocytes

Front 121

CXR of a patient infected with P carinii will show _ opacities with _ appearance.

Back 121

interstitial linear opacities with hazy ground glass appearance on

Front 122

Coccidioides immitis is a _ fungus.

The infective form is _ shaped _.

Back 122

dimorphic fungus

barrel shaped arthrospores

Front 123

How would you treat Coccidioides immitis infections?

How would you treat Histoplasma capsulatum?

Back 123

Amphotericin B and Flucanozole

Amphotericin and Itraconazole

Front 124

Microscopy of Histoplasma capsulatum shows _

Back 124

macrophages that are filled with narrow neck budding yeasts.

Front 125

What is characteristic of Aspergillosis Fumigatus microscopy? What about the CXR in these patients?

Back 125

45 degree branching septate hyphae

Classical air crescent sign on CXR