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Flashcards in Microbiology Deck (126):
1

Bloodstream S. aureus Infections due to ___________

Use of intravascular devices/catheters

2

Pasteurella

From cat and dog bites --> acute soft tissue infection

3

SSPE (Subacute sclerosing panencephalitis)

- Ataxia, myoclonus, visual problems, strange behavior
- Rare complication of measles (with mutated or absent matrix protein) several years later
- Viral nucleocapsids accumulate in neurons

4

Anti-hemagglutinin antibodies:

main mechanism to prevent re-infection with influenza virus

5

HIV Esophagitis

- Candida: MC, adherent white pseudomembrane, erythematous base
- HSV-1: punched out ulcers
- CMV: linear ulceration

6

90 degree angle non-septate hyphae:

Mucormycosis and Rhizopus

7

45 degree angle septate hyphae:

Aspergillus

8

HBV (dsDNA virus):

Replicates by dsDNA → +RNA template → dsDNA progeny
- Replicates via reverse transcription even though it is a DNA virus

9

Rabies binds:

Ach receptors then travels retrograde to CNS

10

Sickle cell asplenic patients MC infected with:

MC infected with encapsulated organisms (s. pneumo mainly, and H. influenza 2nd MC)

11

_______ can be transmitted by Dogs/puppies

Campylobacter and Yersinia

12

_________ Ferments Mannitol

Staph aureus

13

Necrotizing Fasciitis (flesh eating disease):

S. pyogenes, s. aureus, c. perfringens

14

Common Infection After Lung Transplants

CMV

15

Characteristics of Gm (-) Rods

inner and outer membrane, no nuclear membrane, not all are sensitive to penicillins

16

Papovavirus

Family of DNA viruses including polyoma and papilloma

17

Replicate in Nucleus

- All DNA viruses except Pox
- Retrovirus and Influenza replicate in the nucleus

18

Replicate in Cytoplasm

- All RNA viruses (except retro and influenza)
- Poxvirus (DNA virus)

19

Non-infectious

- Pox and hepadna out of the DNA and all the –sense RNA were NOT infectious

20

Aspergillus

May have a “broom” like appearance on silver stain
- Does vascular invasion to facilitate disease

21

S. Japonicum

Intestinal schistosomiasis

22

S. Mansoni

Hepatic schistosomiasis

23

Naegleria Fowleri

amoeba in pools causing Meningoencephalitis in healthy swimmers/divers

24

Acanthamoeba

amoeba causing Meningoencephalitis in immunocompromised patients

25

Mumps in 1st trimester

(teratogenic) → aqueductal stenosis

26

Actinomyces Israelli

yellow sulfur granules (yellow pus), can be found in normal oral flora

27

Diphtheria Toxin

inactivates EF-2

28

Pertussis Toxin

ADP ribosylates Gi → increased cAMP

29

Adenovirus

MC viral cause of acute hemorrhagic cystitis
dsDNA virus so DNA dep DNA pos used to replicate its genome

30

Congenital CMV

blueberry muffin baby, periventricular calcifications, hearing loss

31

Congenital Rubella

blueberry muffin baby (TTP), cataracts, deafness, and PDA

32

Common in Daycares

- Rotavirus is MC in daycares (no blood).
- Shigella is also common in daycares (bloody diarrhea)

33

Group D Strep (Enterococcus)

catalase (-), grows in hypertonic NaCl and in bile
- GU tract is MC portal of entry (procedures)

34

Novobiocin

Staph. Epidermis: sensitive
Saprophyticus: resistant

35

Bacitracin

S. pyogenes: Sensitive
Agalactiae (group B): Resistant

36

M protein

S. pyogenes; prevents phagocytosis

37

Optochin

S. pneumo: sensitive (also bile soluble)
Viridans: resistant

38

Post-strep GN after:

Strep skin or throat infection

39

Rheumatic Fever only after:

Strep Throat

40

CMV: AIDS vs Immunocompetent

- Retinitis is the MC manifestation in AIDS patients, also esophageal ulcers
- subclinical mono-like infection in immune competent

41

Envelope From Host Nuclear Membrane

Herpesviruses

42

Pseudomonas aeruginosa

- blue green pus with fruity odor
- Aw/ cystic fibrosis very commonly, and burns

43

Bacillus anthracis (anthrax)

nonhemolytic rough gray colonies

44

Reactive Arthritis

- due to Chlamydia or Campylobacter
- Can’t see, can’t pee, can’t climb a tree (joint paint)

45

CAMP test

Done in infants for Group B Strep (agalactiae)

46

Malaria: 48 hour periodicity of fever spikes

p. Vivax and p. Ovale

47

Malaria: MC cause

p. Vivax

48

Malaria: Very severe hemolytic anemia, pulmonary edema, renal failure

p. Falciparum

49

Malaria: 72 hr fever cycle

p. Malariae

50

Thayer Martin

To culture Neisseria Gonorrhea

51

Yersinia Enterolytica

pseudoappendicitis (can be due to contaminated milk)

52

Brucella Abortus

produces CGD and spontaneous abortions (from areas where there are cattle)

53

Mycoplasma Pneumoniae

- “walking “ pneumonia
- cold agglutinins (IgM) → mild anemia

54

MC Causes of Conjunctivitis

haemophilus, staph aureus, step pneumo, and Moraxella

55

Need Factors X and V for Growth

- Haemophilus influenza
- Can co-culture with staph aureus on blood agar which will lyse blood cells and release factors needed for growth

56

Maraviroc vs Enfurvitide

HIV Tx:
gp121 (maraviroc) is attachment
gp41 (enfurvatide) is penetration

57

Rubella vs Measles: Rash

- Rubella is a fine, non blotchy truncal rash (not as severe as measles)
- Measles is blotchy, maculopapular and starts on the face and moves down

58

Lipid A

responsible for the toxic properties of LPS of Gm(-) bacteria that cause sepsis and shock

59

E. Coli: fimbria

Pyerlonephritis and cystitis

60

E. Coli: K capsule

Meningitis and Pneumonia (resists complement and phagocytosis)

61

E. Coli: LPS (lipid A)

Shock/sepsis

62

Only organism w/ D-glutamate capsule

Bacillus anthracis

63

Candida Immune Defense

- Local: T lymphocytes (common in HIV pts) and PPD skin test
- Disseminated: neutrophils (systemic disease more common in neutropenic)

64

HIV Genome: gag pol env

- Gag: p24 and p7
- Env: gp120 and gp41 (from gp 160)

65

Segmented RNA viruses

orthomyxo (influenza) and reovirus (rotavirus)
- Capable of genetic shift through reassortment

66

PYR + Test

S. pyogenes

67

Leprosy Types:

- Tuberculoid: + test, TH1 mediated, less severe/hypopigmented lesions w/out sensation
- Lepramatous: - test (due to weak TH1 response), TH2 mediated, more severe/disseminated
- acid fast bacilli that prefers cooler temperatures

68

Malignant Otitis Media (MOE) in diabetics

Pseudomonas

69

Paramyxoviruses

Measles Mumps, RSV, Parainfluenza
- All make multinucleated giant cells (fusion protein/F-protein)

70

HIV binds:

CCR5 (early) or CXCR4 (late)

71

Culture For H. Influenza

chocolate agar with factor V & X (NAD and hematin)

72

Culture for Neisseria

Thayer martin or VPN (vanco, polymyxin, nystatin)

73

Culture for Pertussis

Bordet-genou

74

Culture for Diphtheria

Tellurite or Loffler

75

Culture for TB

Lowenstein-jensen

76

Culture for Mycoplasma

Eaton (requires cholesterol)

77

Culture for Legionella

charcoal yeast extract w/ cysteine and iron

78

Culture for Fungi

sabouraud

79

Culture for Lactose Fermenting

MacConkey
(E.coli: on EMB, green sheen)

80

Obligate Aerobes

Pseudomonas, Nocardia, TB

81

Obligate Anaerobes

Actinomyces, Bacteroides, Clostridium
- foul smelling

82

Obligate Intracellular

Chlamydia & Rickettsia (can’t make own ATP)

83

Encapsulated Organisms

SHiNE SKiS

84

Organisms w/ IgA Protease

SHiN

85

Catalase +

(distinguish staph from strep)
- my CAT’s SECS PAL is Burke the Cardiologist who has a HELICOpter
- S. aureus, e. coli, candida, serratia, pseudomonas, aspergillus, listeria, burkholderia, norcardia, H.pylori

86

Urease +

PS urease has CHUNKS
- Proteus, s. epidemis, Cryptococcus, h. pylori, ureaplasma, nocardia, klebsiella, saprophyticus

87

"A" virulence factors: Lipid, Exotoxin, Protein

- Lipid A: endotoxin part of gram (-) outer membranes; responsible for sepsis/shock
- Exotoxin A (S. pyogenes: superantigen for toxic shock)
(Pseudomonas: host cell death, inactivates EF-2)
- Protein A: S. aureus, prevents opsonization and phagocytosis by binding Fc-IgG

88

Lecithinase

C. Perfringens (phospholipase) – alpha toxin
- Gas gangrene and also food poisoning

89

C. Diff Diarrhea: Mechanism

Cytoskeletal Actin Disruption

90

Lactose Fermenting

Citrobacter, Klebsiella (fast), E. coli (fast), Enterobacter, Serratia

91

Shigella vs Salmonella: Hydrogen Sulfide

Shigella cannot produce hydrogen sulfide, Salmonella can

92

Oxidase +

Campylobacter, v. cholera, H. pylori, Pseudomonas

93

Cryptosporidium

Severe diarrhea in HIV (watery in immune competent)
- Don’t confuse with Cryptococcus or Coccidiodes

94

Tx for Toxoplasma Gondii

sulfadiazine + pyrimathamine

95

Pneumocystis Jerovecii Prophylaxis

dapsone or atovaquone

96

Trypanosoma Brucei:

- African Sleeping Sickness
Tx: Suramin (for blood borne) and melarsprol (for CNS penetration)
- Rhodesiense: east (rapid)
- Gambiense: west (chronic)

97

Malaria Tx:

- Start with Chloroquine
- If resistant: mefloquine or atovaquone/proguanil
- If life threatening: IV Quinidine (unless G6PD)
- If vivax or ovale: add Primaquine (for intrahepatic/hypnozoite stages)

98

Tx for T. Cruzi

benznidazole or nifurtimox

99

Enterobius vermicularis w/ Tx

Scotch tape test, perianal itch
Tx. Bendazoles or pyrantel pamoate

100

Ascaris Lumbricoides w/ Tx

Giant roundworm, ingested, tinkly sound
Tx. Bendazoles or pyrantel pamoate

101

Strongyloides stercoralis w/ Tx

cutaneous infection
- Tx. Albendazole or Ivermecten

102

Ancylostoma or Necator w/ Tx

(hookworms): suck blood from intestine → anemia
o Tx. Bendazoles or pyrantel pamoate

103

Tx for Tapeworms and Flukes

Typically use praziquantal
- If cysts from ingestion of organism eggs: use Albendazole
- Preinject echinococcus cysts with alcohol to kill before removing

104

Mucosal Biopsy necessary for:

Rhizopus/mucor (90 degree angles)

105

HCV Envelope Proteins

Antigenic structure varies so much that production of host antibodies always lags behind

106

Pyrrolidonyl arylamidase +

GAS (S. pyogenes)

107

Dermacentor Tick Carries:

Rickettsia and Franciscella

108

Ixodes Tick Carries:

Borrelia Burgdorferi, Babesia, and Anaplasma

109

Morula in Cytoplasm

Anaplasma (granulocytes) or Erlichiosis (monocytes)

110

Protein A of Staph Aureus

Binds Fc portion of IgG impairing complement activation, opsonization, and phagocytosis

111

HBV and Hepatocellular Carcinoma

Viral DNA integration into host genome hepatocytes triggers neoplastic change

112

STD: Lack of peptidoglycan in cell wall

Chlamydia
Ureaplasma lacks a cell wall completely
- this is why ceftriaxone does not work, must use azithromycin

113

Polyarteritis Nodosa is commonly aw/:

HBV

114

Neonatal Exposure to HBV (from an HBeAg+ mother)

High risk of chronic infection, high levels of replication (due to immature immune system), but only mildly elevated liver enzymes

115

Parvovirus in Adults

arthritis (mimics RA)

116

E. Histolytica

Abdominal pain, cramping, and bloody diarrhea
Trophozoites are multinucleate and typically possess phagocytosed erythrocytes within cytoplasm

117

Salmonella: Appearance

Gm (-) rods

118

Vesicles of HSV1

All should contain the same virus so same appearance on a gel

119

Acid Fast, grows at 41 degrees

MAC
- disseminated infection in HIV+ patients with less than 50 CD4

120

Pyocyanin of Pseudomonas

Functions fro generate ROS to kill competing microbes

121

Leptospirosis

Water contaminated with animal urine
Common in surfers and in tropics
Photophobia with conjunctival suffusion, jaundice, flulike sx
-Weil disease- severe form with jaundice and azotemia

122

Liver abscess (anchovy paste), flask shaped ulcers in colon

Entamoeba histolytica
- RBCs in cytoplasm

123

Hg fever, black vomitus, jaundice

Yellow fever

124

Hairy Leukoplakia aw/

EBV

125

Macular rash and febrile seizure in infant

HHV6 roseola

126

Jarisch-Herxheimer

Reaction to release of bacterial pyrogens following antibacterial use