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Flashcards in Bacteriology EC Deck (108):
1

Peptidoglycan Function

Gives rigid support
Protects against osmotic pressure

(What stains on gram stain)

2

Major surface antigen of Gram+

Lipoteichoic acid (induces TNF/IL-1)

Cell wall (made of peptidoglycan)

3

Major surface antigen of Gram -

LPS/Endotoxin/Outer membrane

Lipid A induces TNF/IL-1
O polysaccharide is the anitgen

4

What is the periplasm?

Space between cytoplasmic membrane and outer membrane in gram -

Contains BETA-LACTAMASE

5

How do beta-lactams work?

Inhibit cross-linking of peptidoglycan by transpeptidase

6

Gram + Bacteria (gram stain color, major antigen, vulnerability to beta-lactams)

BLUE
Thick cell wall/peptidoglycan (+ is thick)
Lipoteichoic acid
Vulnerable to beta-lactams/lysozymes

7

Gram - Bacteria (gram stain color, major antigen, vulnerability to beta-lactams)

RED
Thin cell wall/peptidoglycan (- is thin)
LPS (lipid A) Endotoxin
Resistant to beta lactams/lysozymes (beta-lactamase in periplasmic space)

8

What are the gram + bacteria?

Mycobacterium (acid fast)
Gardnerella
Staph
Strep
Corynebacterium
Actinomyces
Nocardia
Bacillus
Listeria
Clostridium

"My God, Some Silly Corny Actors kNock Back Listerine in the Closet"

9

What Gram + bacteria commonly cause disease and what is their morphology?

Streptococcus
Enterococcus
Staphylococcus
Bacillus (spore forming)
Clostridium (spore forming)
Corynebacterium (rods)
Listeria (rods)

10

What are the morphologies of the Gram - bacteria?

Neisseria (diplococcus)

Treponema pallidum (spirochete)

REST=rods/pleomorphic

11

What stain identifies mycobacterium?

Acid fast (causes TB and leprosy)

12

What bacteria have unusual cell membranes/walls?

Mycoplasma - STEROLS and NO CELL WALL

Mycobacterium - MYCOLIC ACID and HIGH LIPID CONTENT

13

What bacteria do not Gram stain well?

Treponema (too thin- use darkfield microscope)
Rickettisa (intracellular)
Mycobacteria (lipid content detected in acid fast stain
Mycoplasma (no cell wall)
Legionella (intracellular)
Chlamydia (intracellular)

"These Rascals May Microscopically Lack Color"

14

What bugs stain with Giemsa?

Chlamydia
Borrelia
Rickettsiae
Trypanosome
Plasmodium

"Certain Bugs Really Try my Patience"

15

What bugs stain with PAS (periodic acid-Schiff)?

Tropheryma whipplei

(Stains glycogen)

"PAS the sugar"

16

What bugs stain with Ziehl-Neelsen?

Acid fast

Nocardia
Mycobacterium

17

What bugs stain with India Ink?

Cryptococcus neoformans

18

What bugs stain with Silver stain?

Fungi (ie Pneumocystis)
Legionella
H. pylori

19

What does catalase do?

Breaks down hydrogen peroxide radicals

20

What does peroxidase do?

Breaks down hydrogen peroxide radicals

21

What does superoxide dismutase do?

Breaks down superoxide radicals

22

What are obligate aerobes?

Must use oxygen - same enzymes as us

23

What are the obligate aerobes?

Nocardia
Pseudomonas
Mycobacterium TB
Bacillus

"Nagging Pests Must Breathe"

24

What are facultative anaerobes?

Have the faculty to be anaerobic (comparable to skeletal muscle during sprinting)

Prefer O2, but switch if have to

25

Are obligate anaerobes?

Hate oxygen (no enzymes to defend against it)

26

What are the obligate anaerobes?

Clostridium
Bacteroides
Actinomyces

"Can't Breathe Air"

AninOglycosides are ineffective because they require O to enter cell

27

What bugs are obligate intracellular?

Rickettsia
Chlamydia
(can't make own ATP)

"stay inside when it gets Really Cold"

28

What bugs are facultative intracellular?

Salmonella
Neisseria
Brucella
Mycobacterium
Listeria
Francisella
Legionella
Yersinia

"Some Nasty Bugs May Live FacultativeLY"

29

What does the Quellung reaction test for?

Encapsulated bacteria

"Quellung=Swelling"

30

What bacteria are encapsulated?

E. coli
Strep. pneumoniae
Klebsiella pneumoniae
H. influenzae
Neisseria meningitidis
Salmonella
B Strep

"Even Some Killers Have Nice Shiny Bodies"

31

What organisms would someone with chronic granulomatous disease get recurrent infections from? Why?

Catalase + organisms
Pseudomonas
Listeria
Aspergillus
Candida
E. coli
S. aureus
Serratia

"you need PLACESS for your CATs"

People with CGD have a NADPH oxidase deficiency
Catalase + bacteria neutralize limited H2O2 produced

32

What bugs are urease +?

Cryptococcus
H. pylori
Proteus
Ureaplasma
Nocardia
Klebsiella
S. epidermidis
S. saprophyticus

"CHuck norris hates PUNKSS"

33

What bacteria produce pigment?

Actinomyces ISRAELii - yellow sulfur granules "Israel has yellow sand"

S. aureus - yellow pigment "aureus=gold'

Pseudomonas AURUGinosa - blue-GREEN pigment "AERUGala is GREEN"

Serratia MARCESCENS - RED pigment "red maraschino cherries"

34

Corynebacterium diphtheriae (Toxin, Mechanism, Manifestation)

Diptheria toxin

Inactivates EF-2 (elongation factor)

Pseudomembranous pharyngitis
Severe lymphadenopathy ("bull neck")

35

Pseudomonas aeruginosa (Toxin, Mechanism, Manifestation)

Exotoxin A

Inactivates EF-2 (elongation factor)

Host cell death

36

Shigella (Toxin, Mechanism, Manifestation)

Shiga toxin

Inactivates 60S ribosome (remove adenine from rRNA)

GI mucosal damage --> dysentery
Cytokine release --> HUS

37

EHEC O157:H7 (enterohemorrhagic E. coli) (Toxin, Mechanism, Manifestation)

Shiga Like Toxin

Inactivates 60S ribosome (remove adenine from rRNA)

Enhances cytokine release --> HUS
Does no invade host cells

38

ETEC (enterotoxigenic E. coli) (Toxin, Mechanism, Manifestation)

Heat-LABILE (LT) - overactivates adenylate cyclase, increase cAMP, increase CL and water secretion

Heat-STABLE - overactivates guanylate cyclase, increased cGMP, decreased NaCl and H2O resorption

Watery diarrhea results

"Labile in the Air (Adenylate cyclase)
Stable on the Ground (Guanylate cyclase)"

39

Bacillus anthracis (Toxin, Mechanism, Manifestation)

Edema factor

Mimics adenylate cyclase (increased cAMP)

Edematous borders of black eschar in cutaneous anthrax

40

Vibrio cholerae (Toxin, Mechanism, Manifestation)

Cholera toxin

Permanently activates Gs (increased cAMP)
Cl secretion and H2O efflux

"Rice water" diarrhea

41

Bordetella pertussis (Toxin, Mechanism, Manifestation)

Pertussis toxin

Disables Gi (increased cAMP)
Inhibits phagocytosis

Whooping cough

42

Clostridium tetani (Toxin, Mechanism, Manifestation)

Tatanospasmin

Cleave SNARE and prevent release of GABA/glutamate

Spastic paralysis "Lock jaw"

43

Clostridium botulinum (Toxin, Mechanism, Manifestation)

Botulinum toxin

Cleave SNARE and prevent release of ACh

Flaccid paralysis "Floppy baby"

44

Clostridium perfringens (Toxin, Mechanism, Manifestation)

Alpha toxin

Phospholipase that degrades tissue and cell membranes

Myonecrosis (gas gangrene)
Hemolysis (double zone hemolysis)

45

Streptococcus pyogenes (Group A) (Toxin, Mechanism, Manifestation)

Streptolysin O

Protein that degrades cell membrane

Lyse RBCs (beta-hemolysis)

*host antibodies to streptolysin O (ASO) used to diagnose rheumatic fever*

*Exotoxin A can also cause toxic shock syndrome (superantigen)*

46

Staphylococcus aureus (Toxin, Mechanism, Manifestation)

TSST-1 (toxic shock syndrome toxin)

Bring MHCII and TCR together without antigen resulting in superantigen with overwhelming release of IFN-gamma and IL-2 --> shock

Toxic shock syndrome (fever, rash, shock)

*Exfoliative toxin causes scalded skin syndrome*
*Enterotoxin causes food poisoning*

47

Septic shock (Mechanism, Major players, Manifestations)

Endotoxin=LPS found in gram negative bacteria (LIPID A)

Release of LPS from lysis of gram - (or fungi) cause excessive release of TNF and IL-1

Edema
NO
DIC/Death
Outer membrane
TNF
O-antigen
Xtremely heat stable
Il-1
Neutrophil chemotaxis

48

Transformation (what is it?, what bacteria utilize?)

Take up naked DNA
"Take this DNA and be TRANSFORMED"

S. pneumo
H. influenzae
Neisseria

"SHiN"

49

Conjugation

Bacteria sex (passing plasmids)

F+ uses sex pilus (penis) to transfer DNA to F- (making it F+)

50

Transposition

DNA that can jump from one location to another

(Can jump into plasmid and be transferred to another bacteria)

51

Transduction

Transduced by a bacteriophage (virus)

Generalized (Lytic phage): Phage infects, picks up some DNA, infects another and transfers genes

Specialized (Lysogenic phage): viral DNA incorporates into chromosome, when excised, flanking gene excised with it, other bacteria then infected.

52

What bacterial toxins genes are encoded for by lysogenic phages (Specialized transduction)?

shigA-like toxin
Botulinum toxin
Cholera toxin
Diptheria toxin
Erythrogenic toxin of Strep. pyogenes

"ABCDE"

53

Determination of coagulase - Staph

NOvobiocin test
Saprophyticus is Resistant
Epidermidis is Sensitive

"on the office STAPH retreat there was NO StRESs"

54

Determination of alpha hemolytic Strep

Optochin test
Viridans is Resistant
Pneumoniae is Sensitive

"OVRPS" (overpass)

55

Determination of beta hemolytic Strep

Bacitracin test
group B (agalactiae) are Resistant
group A (pyogenes) are Sensitive

"B-BRAS"

56

What are the beta-hemolytic bacteria?

staph. Aureus
strep. Pyogenes
strep. Agalactiae
Listeria

"I have A-PAL who's beta-hemolytic"

57

Staphylococcus aureus (Morphology, Virulence, Disease)

Gram + cocci in clusters
(b/c catalase + can form fibrin clot around self leading to abcess)

Protein A binds Fc-IgG (inhibits complement fixation/phagolysis)

Skin infections, Organ abscess, Pneumonia
Toxic shock syndrome, Scalded skin syndrome, Rapid onset food poisoning (toxin mediated)
Acute bacterial endocarditis/osteomyelitis
MRSA (altered penicillin binding protein)

58

Staphylococcus epidermidis (Morphology, Virulence, Disease)

Gram + Cocci (catalase+, coagulase -)

Biofilms

Prosthetic devices/catheters
Contaminates blood cultures (normal skin flora)

59

Streptococcus pneumoniae (Morphology, Virulence, Disease)

Gram + cocci (catalase -, alpha hemolytic, optochin sensitive)

Encapsulated
IgA protease (allows adherence to mucus membranes)

"MOPS"
Meningitis
Otitis media
Pneumonia
Sinusitis

"strep. pneumo MOPS are MOst OPtochin Sensitive"

60

Viridans strep (Morphology, Virulence, Disease)

Gram + cocci (alpha hemolytic, optochin resistant)

Strep. sanguis=blood (endocarditis-sticks via glyocalyx)
Strep. mutans=dental caries

61

Strep. pyogenes [group A] (Morphology, Virulence, Disease)

Gram + cocci (beta hemolytic, Bacitracin sensitive)

Pyogenic - pharyngitis, cellulitis, impetigo

Toxigenic - scarlet fever, toxic shock-like syndrome, necrotizing fasciitis

Immunologic-rheumatic fever, acute glomerulonephritis (antibodies to M protein help clear infection but cause)

62

What are the JONES criteria to diagnose rheumatic fever?

Joints - polyarthritis
Heart - endocarditis
Nodules - subcutaneous
Erythema marginatum
Sydenham's chorea

" (s. pyogenes) Pharyngitis can cause PHever and glomerulonePHritis"

63

Strep. agalactiae [group B] (Morphology, Virulence, Disease)

Gram + cocci, (beta hemolytic, Bacitracin resistant)

CAMP factor (enlarges s. aureus hemolysis)

colonizes vagina
BABIES - pneumonia, meningitis, sepsis

Hippurate test positive

"group B for Babies"

64

Enterococci (Morphology, Virulence, Disease)

Gram + cocci, (no hemolysis)

E. faecalis, E faecium
Normal colonic flora

UTI, biliary tract infections, endocarditis

VRE (vancomycin-resistant enterococci) important nocosomial

65

Strep bovis (Morphology, Virulence, Disease)

Gram + cocci (no hemolysis)

Colonizes gut (bacteremia in colon cancer pt's)

"Bovis in the Blood= Cancer in the Colon"

66

Corynebacterium diptheriae (Morphology, Virulence, Disease)

Gram +

Exotoxin encoded by beta-prophage
ADP ribosylates EF-2

Pseudomembranous pharyngitis
Lymphadenopathy
Myocarditis (arrhythmia)

Meta-chromatic granules
Elek test for toxin

67

Clostridium tatani (Morphology, Virulence, Disease)

Gram +, spore forming

Produces TETANOSPASMIN
Cleaves SNARES and inhibits GABA/glycine release

Spastic paralysis

68

Clostridium botulinum (Morphology, Virulence, Disease)

Gram +, spore forming

Botulinum toxin cleaves SNAREs and inhibits ACh release

Flaccid paralysis (floppy baby)

69

Clostridium perfringens (Morphology, Virulence, Disease)

Gram +, spore forming

Alpha toxin (lecinthinase)

Myonecrosis (gas gangrene)

"PERFringens PERForates a gangrenous leg"

70

Clostridium difficile (Morphology, Virulence, Disease)

Gram +, spore forming

Toxin A (enterotoxin) - binds brush border

Toxin B (cytotoxin) - destroys cytoskeleton of enterocytes
PSEUDOMEMBRANOUS COLITIS (often secondary to clindamycin or ampicillin)

treat w/ metronidazole or vancomycin

71

Bacillus anthracis (Morphology, Virulence, Disease)

Gram +, Spore forming
(Only bacteria with polypeptide capsule)

Lethal factor/Edema factor - Cutaneous anthrax - black eschar

Inhalation of spores - flu-like progress to fever, pulmonary hemorrhage, mediastinitis, and shock

(Woolsorter's disease - inhalation of spores in contaminated wool)

72

Bacillus cereus (Morphology, Virulence, Disease)

Gram +

Reheated rice - spores germinate and produce enterotoxin (cereulide)
Diarrhea

73

Listeria monocytogenes (Morphology, Virulence, Disease)

Gram + intracellular

Ingestion of unpasteurized milk/deli meat
"ACTIN ROCKETS"/tumbling motility

Amnionitis, Septicemia, Spontaneous abortion
Granulomatosis infantiseptica, Neonatal/Immunocompromised meningitis,

74

Actinomyces (Morphology, Virulence, Disease)

Gram + Long branching filaments (look like fungi)

Normal oral flora
Cause abscess that drain through sinus tract forming 'SULFUR GRANULES"

75

Nocardia (Morphology, Virulence, Disease)

Gram +, long branching filaments (look like fungi)

Found in soil

Immunocompromised - pulmonary infections
Immunocompetent - skin infection after trauma

76

Mycobacterium tuberculosis

ACID FAST

Primary - Gohn complex in mid lung
Secondary - Caseating granuloma in upper lung (reactivation)

Extrapulmonary:
CNS (parenchymal tuberculoma or meningitis)
Pott's disease (vertebral body)
Lymphadenitis
Renal
GI

*PPD skin test - in sarcoidosis, immunocompromised, BCG vaccine*

77

TB symptoms

Fever
Night sweats
Weight loss
Hemoptysis

78

Mycobacterium avium

ACID FAST

Disseminated disease in AIDS

prophylaxis with AZITHROMYCIN

79

Mycobacterium leprae

ACID FAST

Infects skin and superficial nerves "glove and stockings"
Armadillos - reservoir

Lepromatous - Skin (contagious)
Low cell mediated immunity - Humoral TH2 response

Tuberculoid - few skin plaques
High cell mediated immunity - TH1 response

Treat with DAPSONE + RIFAMPIN + CLOFAZIMINE

80

Neisseria gonorrhoeae

Gram - diplococci
Produce IgA protease

Ferments glucose (not maltose)

Gonorrhea
Septic arthritis
Neonatal conjunctivitis
PID
Fitz-Hugh-Curtis syndrome (post PID adhesions to liver)

81

Neisseria meningitidis

Gram - diplococci
Produce IgA protease

Ferments glucose AND maltose

Meningitis
Waterhouse-Friderichsen syndrome (bleed into adrenal glands)

82

Haemophilus influenzae

haEMOPhilus (usually vaccinated against)

Epiglotitis (cherry red children)
Meningitis
Otitis media
Pneumonia

Culture of chocolate agar (requires factor V and X)

83

Legionella pneumophila

(lover water)
Legionnaire's disease - pneumonia, fever, GI, CNS

Pontiac fever - flu-like

Use SILVER STAIN, grow on CHARCOAL yeast culture with IRON and CYSTINE

"French Legionnaire with his SILVER helmet around a campfire (CHARCOAL) with his IRON dagger. He's no sissy (CYSTEIN)"

84

Pseudomonas aeruginosa

PSEUDOmonas (loves water)

Pneumonia
Sepsis
External otitis
UTI
Diabetic osteomyelitis

Produces green/blue pigment w/ grapelike odor

85

EIEC

INVASIVE

No toxins

Bloody diarrhea

86

ETEC

TRAVELER'S DIARRHEA

Heat labile (cAMP)/stabile toxin (cGMP)

Watery diarrhea

87

EPEC

PEDS

Adheres and interfere's with absorption

88

EHEC O157:H7

HEMOLYTIC UREMIA SYNDROME (anemia, thrombocytopenia, acute renal failure)

Shiga-like toxin (inactivates 60S ribosome)

89

Klebsiella

Intestinal flora

Lobar pneumonia in alcoholics and diabetics when aspirated

"Currant jelly sputum" - very mucoid w/ polysaccaride capsule

90

Salmonella typhi

Spreads hematogenously

Invades and produces bloody diarrhea

TYPHOID FEVER (remain in gallbladder as carrier)
red spots on abdomen
fever
headache
diarrhea

91

Shigella

Produces shiga toxin - diarrhea

Spreads cell to cell

92

Campylobacter jejuni

Bloody diarrhea in children
Fecal oral through foods

Can cause Guillain-barre and Reactive arthritis

93

Vibrio cholerae

RICE WATER DIARRHEA

Cholera toxin permanently activates Gs

94

Yersinia enterocolitica

Pet feces (dog)

Mesenteric adenitis
can mimic Chrohn's or appendicitis

95

Helicobacter pylori

Risk for PUD, gastric adenocarcinoma, lymphoma

Urease +

96

What are the common spirochetes?

BLT

Borrelia
Leptospira
Treponema

97

Leptospira interrogans

Water contaminated with animal urine

LEPTOSPIROSIS: flu, jaundice, photophobia,
SURFERS

Weil's disease - jaundice, liver and kidney dysfunction, fever, hemorrhage, anemia

98

Borrelia burgdorferi

Lyme disease

Ixodes tick

Erythema chronicum migrans
Neurologic (Bell's palsy)
Cardiac (AV node involvement)
Musculoskeletal
CNS

99

Treponema pallidum

SYPHILIS (detected with VDRL)

Primary- painless chancre
Secondary - Rash on palms and soles, Codylomata lata
Tertiary - Gummas, Neurosyphilis (tabes dorsalis)

Argyll Robertson pupil - constricts to accommodate but unreactive to light

100

Congenital syphilis

Saber shins
Saddle nose
CN VIII deafness
Hutchinson's teeth
Mulberry molars

101

Jarisch-Herxheimer reaction

Flu-like syndrome after antibiotics are started in syphilis infection (due to lysed bacteria)

102

Gardnerella vaginalis

Vaginosis

"Fishy smelling" gray vaginal discharge

Clue cells

103

Rickettsia rickettsii

Rocky Mountain spotted fever (tick bourne)

Starts on WRISTS AND ANKLES
Spreads to TRUNK, PALMS AND SOLES

104

Rickettsia prowazekii

tick borne (like RMSF)

Starts on TRUNK (spares palms and soles)

105

What infections produce a rash on the palms and soles?

"you drive CARS using your palms and soles"

Coxsackievirus A (hand, foot, and mouth)
Rocky mountain spotted fever
Syphilis

106

Chlamydiae trachomatis

Elementary body Enters cell by Endocytosis
Reticulate body Replicates

Types A-C: Conjunctivitis/Blindness (#1 cause)

Types D-K: Urethritis, PID, neonatal pneumonia (staccato cough)

Reactive arthritis

107

Chlamydiae pneumoniae

Causes atypical pneumonia

108

Mycoplasm pneumoniae

Atypical "walking" pneumonia

HEADACHE
NONPRODUCTIVE COUGH
DIFFUSE INTERSTITIAL INFILTRATE

Cold agglutinins (IgM)

Outbreaks in military recruits and prisons

Decks in Evan's Step 1 Prep Material Class (72):