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Bacteriology Flashcards

1
Q

Features unique to Gram (+)

A

Spores
No outer membrane
Thicker peptidoglycan cell wall (peptidoglycan is crosslinked by transpeptidase)
Lipoteichoic acid that extends from the cytoplasmic membrane to exterior to induce TNF alpha and IL1

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2
Q

Features unique to Gram (-)

A

Outer membrane that consists of a outer leaflet (endotoxin/LPS), Porin for transport embedded in membrane, Inner leaflet which is just phospholipids

Outer membrane functions as an endotoxin : Lipid A induces TNF alpha and IL-1. Antigenic O polysaccharide component

Periplasmic space (Beta lactamase lcoation)

Think peptidoglycan wall thats covered by the outer membrane

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3
Q

Bacteria that cannot be gram stained

A 
These- Treponema 
Little - Leptospira
Microbes - Mycobacteria
May- Mycoplasma
Unfortunately - Ureaplasma
Lack - Legionella
Real - Rickettsia
Color - Chlamydia
But - Bartonella
Are - Anaplasma 
Everywhere - Ehrlichia
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4
Q

Giemsa stain

A 
Rickettsia
Chlamydia
Trypanosomes
Plasmodium
Borrelia

“Ricky got Chlamydia Trying to Pass Borrelia near Giemsa”

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5
Q

Periodic Acid - Schiff stain

A

stains glycogen

Dx Whipple disease (Tropheryma whipplei)

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6
Q

Ziehl Neelsen Stain (carbol fuchsin)

A

Acid fast bacteria (i.e. mycobacteria) - stains the mycolic acid in cell wall

Protozoa (cryptosporidium oocyts)

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7
Q

India ink stian

A

cryptococcus neoformans

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8
Q

Silver stain

A

Fungi (coccidiodes and pneumocystis jirovecci)
Legionella
Helicobacter pylori

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9
Q

Fluorescent antibody stain

A

Many bacteria and viruses

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10
Q

Chocolate agar

A

H influenzae

Factors V (NAD+) and X (hematin)

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11
Q

Thayer-Martin Agar

A

Neisseria gonorrhoeae and meningitidis

inhibit the growth of gram (+) organisms with vancomycin

inhibits the growth of gram (-) with Trimethoprim and Colistin

Inhibits fungi with Nystatin

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12
Q

Bordet-Gengou agar

A

Bordetella pertussis

or Regan Lowe medium (charcoal blood and antibiotic)

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13
Q

Tellurite agar

Loffler medium

A

C diphtheriae

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14
Q

Lowenstein Jensen agar

A

M tuberculosis

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15
Q

Eaton agar

A

Requires cholesterol

M Pneumoniae

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16
Q

MacConkey Agar

A

Lactose fermenting enterics

PH indicator - lactose fermenters will convert lactose to acidic metabolites which causes color change

Fermentation produces acid causing colonies to turn pink

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17
Q

Eosin- methylene blue (EMB) agar

A

E coli

colonies with green metallic sheen

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18
Q

Charcoal yeast extract agar buggered with cysteine and iron

A

Legionella

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19
Q

Sabouraud agar

A

Fungi

“sabs a fun guy”

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20
Q

Aerobes

A

“Nagging Pests Must Breathe”

Nocordia
Pseudomonas aeruginosa
MycoBacterium tuberculosis (apex of lung)
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21
Q

Anaerobes

A

” Anaerobes Cant breathe Fresh Air”

Clostridium
Bacteroides
Fusobacterium
Actinomyces israelii

lack catalase and or superoxide dismutase and are thus susceptible to oxidative damage

Aminoglycosides are ineffective against anaerobes because these antibiotics require O2 to enter the bacterial cell. Think Amin(O2)glycosides

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22
Q

Facultative anaerobes

A

Strep, staph, and enteric gram (-)

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23
Q

Obligate intracellular

A

stay inside because its Really CHilly and COld

Rickettsia
CHlamydia
COxiella

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24
Q

Encapsulated Bacteria

A

Please SHiNE my SKiS

Pseudomonas aeruginosa
Streptococcus pneumoniae
Haeumophilus influenxae type b
Neisseria meningitidis
E Coli
Salmonella
Klebsiella pneumoniae
Group B strep

Are opsonized and then cleared by spleen. A splenic pts therefore are at increased risk and need vaccines agains N meningitidis, S pneumo, H influenzae “No Spleen Here”

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25
Q

Urease positive organisms

A

Pee CHUNKS

P-proteus
C-Cryptococcus
H- H pylori
U- Ureaplasma
N-Nocardia
K- Klebsiella
S- S epidermidis
S- S saprophyticus

urease hydrolyzes urea to release ammonia and CO2 which increases the PH. this predisposed to struvite (ammonium magnesium phosphate) stones, particularly proteus

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26
Q

Catalase + organisms

A

Cats Need PLACESS to Belch their Hairballs

Nocardia
Pseudomonas
Listeria
Asperfillus
Candida
E coli
Staph
Serratia
B cepacia
H pylori
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27
Q

Pigment colors for:

1) Actinomyces israelii
2) S aureus
3) P aeruginosa
4) Serratia marcescens

A

1) Yellow ( Israel has yellow sand)
2) Gold
3) green
4) red (red sriracha hot sauce)

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28
Q

Which bacteria is important when considering catheter and prosthetic device infections

A

S epidermidis

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29
Q

Which bacteria is important when considering dental plaques and infective endocarditis

A

Viridans streptococci

  • S mutans
  • S sanguinis
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30
Q

Which bacteria is important for resp infections in CF, ventilator associated pneumonia, and contact lens associated keratitis

A

P aeruginosa

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31
Q

Which bacteria is important in Otitis media

A

Nontypeable (unencapsulated) H influenzae

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32
Q

What protein is expressed by S aureus

A

Protein A

it binds Fc region of IgG and prevents opsonization and phagocytosis

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33
Q

IgA protease

A

cleaves IgA –> can colonize mucous membranes

S. pneumo
H influenza type b
Neisseria

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34
Q

M protein

A

M= mimics human cellular proteins

helps prevent phagocytosis

Group A strep

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35
Q

Type III secretion system

A

injectisome

needle like protein appendage that facilitates direct delivery of toxins from certain gram (-) bacteria to eukaryotic host cells

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36
Q

Transformation

A

Bacteria lysis releases short pieces of naked bacterial chromosomal DNA –> competent bacteria binds and imports –> expression

S pneumo
H influenzae type b
Neisseria

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37
Q

Conjugation

A

F+ x F- : A single strand of plasmid DNA is transferred from F+ to F- . F- becomes F+. No chromosomal DNA

Hfr x F- : F+ plasmid can become incorporated into bacterial chromsomal DNA –> high frequency recombination cell (Hfr). F- recipient will remain F- but now recombinant

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38
Q

Transduction

A

Foreign DNA is introduced into a cell by a virus or viral vector

Generalized: Lytic phage. packaging error causes bacterial chromosomal DNA to become package in phage capsid too

Specialized: Lysogenic phage. Viral DNA incorporates into bacterial chromosome. When phage DNA is excised the bacterial genes may be excised with it. DNA is packages into phage capsid and can infect another bacterium
ex: ABCD’S - Group A strep erythrogenic toxin, Botulinum toxin, Cholera toxin, Diphtheria toxin, Shiga toxin

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39
Q

Transposition

A

segment of DNA that can “jump” from one location to another and transfer genes

antibiotic resistnace

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40
Q

Exotoxin vs Endotoxin

A

Exotoxin: some gram + or gram -, polypeptide, vaccines

Endotoxins: outer cell membrane of most gram - bacteria, lipid A component of LPS, can cause fever shock(hypotension) and DIC, induces TNF, IL1, and IL6

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41
Q

This bacteria is gram +, beta hemolytic, catalase +, coagulase +. It has protein A virulence factor.

A

Staph aureus

Protein A - binds Fc-IgG. inhibiting complement activation and phagocytosis

  • Inflammatory disease
  • Toxic shock syndrome (TSST-1) : super antigen that binds MHC II and T cell receptor, resulting in polyclonal T cell activation
  • scalded skin syndrome (exfoliative toxin)
  • rapid onset food poisoning (entertoxins)
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42
Q

This bacteria infects prosthetic devices and IV catheters by producing adherent biofilms?

A

Staph epidermidis

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43
Q

This bacteria is the second most common cause of uncomplicated UTI in young women

A

Staph saprophyticus

first is e coli

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44
Q

This bacteria causes a “rusty sputum”

A

Strep pneumoniae

lancet shaped diplococci
Encapsulated
IgA protease

MOPS (most common cause of) : meningitis, Otitis media in children, pneumonia, sinusitis

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45
Q

This group of bacteria is known for causing dental caries (sp?) and endocarditis (sp?)

A

Viridans group strep

Normal flora of the mouth. Live in the mouth because they are not afraid of the chin (optochin resistant)

Strep mutans and S mitis cause dental caries
Strep sanguinis makes dextrans that bind to fibrin platelet aggregates on damaged heart valves, causing subacute bacterial endocarditis

46
Q

This bacteria can cause scarlet fever and is bacitracin sensitive

A

Strep Pyogenes (group A step)

  • beta hemolyic
  • PYR +
  • hyaluronic acid capsule and M protein inhibit phagocytosis. Antibodies to M protein enhance host defenses against S. pyogenes but can give rise to rheumatic fever.
  • pyogenic: pharyngitis, cellulitis, impetigo (honey crusted lesions), erysipelas
  • toxigenic: scarlet fever, toxic shock like syndrome, necrotizing fasciitis
  • Immunologic- rheumatic fever, glomerulonephritis
  • ASO titer or anti-DNase B antibodies indicate recent S pyogenes infection
47
Q

scarlet fever

A

S pyogenes

blanching, sandpaper like body rash, strawberry tongue, and circumoral pallow in the setting of group A strep pharyngitis (erythrogenic toxin +)

48
Q

Common cause of pneumonia, meningitis, and sepsis in babies

A

Strep agalactiae (group B strep)

Beta hemolytic
CAMP factor
Hippurate test +
PYR -

Screen pregnant women 35-37 weeks. REceive intrapartum penicillin prophylaxis is +

49
Q

Common indicator of colon cancer

A

Strep Bovis

Bovis in the blood = cancer in the colon

Colonizes the gut
Bacteremia and subacute endocarditis
associated with colon cancer

50
Q

Enterococci

A

vancomycin-resistant enterococci are an important cause of nosocomial infection

More resilient than streptococci, can grow 6.5% NaCl and bile

E. Faecalis and E faecium ( think feces because normal colonic flora)

51
Q

The only bacterium that has a polypeptide capsule with D-glutamate

A

Bacillus anthracis

Spore forming rod that produces anthrax toxin
Colonies show a halo of projections, sometimes referred to as “medusa head”

Cutaneous anthrax: painless papule surounded by vesicles. Ulcer with black eschar thats painless and necrotic.

Pulmonary anthrax: Inhalation of spores can cause flu like symptoms that rapidly progress to fever, pulmonary hemorrhage, mediastinitis, and shock. “Woolsorters disease”. widened mediastinum on cxr

52
Q

Pt presents with watery diarrhea 12 hours after eating a plate of reheated rice

A

The spores survive cooking and cause nausea and vomiting iwthin 1-5 hours.

Cereulide is the preformed toxin

water diarrhea

53
Q

Pt presents with spastic paralysis, trismus (lockjaw), risus sardonicus (raised eyebrows and open grin), and opisthotonos (spasms of the spinal extensors).

A

Clostridia tetani

Tetanospasmin exotoxin causes tetanus

It is a protease that cleaves SNARE proteins for NT. It blocks the release of inhibitory NT like GABA and glycine from renshaw cells of the spinal cord

54
Q

pt presents with descending flaccid paralysis

A

Clostridia botulinum

heat labile toxint hat inhibits the release of Ach

Adults: ingestion of preformed toxin
Babies: ingestion of spores in honey lead to floppy baby syndrome (descending flaccid paralysis)

4 Ds: Diplopia, Dysarthria, Dysphagia, Dyspnea

55
Q

Pt presents with a gangrenous leg

A

Clostridium perfringens

Alpha toxin lecithinase that causes myonecrosis (gas gangrene, presents as soft tissue crepitus) and hemolysis

Enterotoxin –> food poisoning when ingested

56
Q

Patients presents with diarrhea and pseudomembranous colitis

A

Clostridia difficile

Toxin A (enterotoxin) binds to the brush border of gut and alters fluid secretion

Toxin B (cytotoxin) disrupts cytoskeleton via actin depolymerization

Esp due to clindamycina nd ampicillin

Tx with metronidazole or oral vancomycin

57
Q

Patients presents with pseudomembranous pharyngitis ?

A

Corynebacterium diphtheriae

pseudomembrane, lymphadenopathy, myocarditis, and arrhythmias

Metachromatic (blue and red) granules and + Elek test for toxin

Endotoxin coded by Beta-prophage causes ADP-ribosylation of EF2 (elongation factor 2) which ultimately inhibits protein synthesis

58
Q

This bacteria is commonly spread by ingestion of unpasteurized dairy products and cold deli meats

A

Listeria monocytogenes

grows at refrigeration temperatures “cold enrichment” at 4-10C

Actin rocket tails and characteristic tumbling motility in broth

Causes spontaneous abortion in pregnant women, granulomatosis infantiseptica, neonatal meningitis, meningitis in immunocompromised patients

tx with ampicillin

59
Q

Pts was dx with HIV and now presents with TB symptoms but a negative PPD. On culture the bacteria is a long branching filament

A

Nocardia

Forms long branching filaments resembling fungi

Aerobe, acid fast, found in soil and causes pulmonary infections in immunocompromised, cutaneous infections in immunocompetent, can spread to CNS

TX with TMP-SMX

60
Q

Patient presents with an oral abscess after having her tooth removed prior

A

Actinomyces

forms long branching filaments resembling fungi

Not acid fast, normal flora, oral abscess after extraction, forms yellow sulfur granules

TX with penicillin

61
Q

TX of Nocardia vs Actinomyces

A

think SNAP

Sulfonamids - nocardia; Actinomyces-penicillin

62
Q

Mycobacteria characteristics

A

all are acid fast organisms (pink rods)

M tuberculosis
M avium (causes dissemniated non-TB disease in AIDS
M scrofulaceum (cervical lymphadenitis in children)
M marinum (hand infection in aquarium handlers)
63
Q

What is the unique “factor” associated with virulent M tuberculosis strains

A

cord factor creates a “serpentine cord” appearance

activates macrophages (promoting granuloma formation) and induces release of TNF alpha

Sulfatides (surface glycolipids) inhibit phagolysosomal fusion

64
Q

Progression of tuberculosis

A

Primary tuberculosis has a Ghon complex (lesions consist of a calcified focus of infection and an associated lymph node). Ghon focus is ususally in the mid/lower lobes

90% will heal by fibrosis but can reactivate into secondary TB which has a fibrocaseous cavitary lesion in the upper lobes

Also risk of bacteremia and miliary TB

65
Q

An acid fast bacillus that likes cool temperatures and therefore infects skin and superficial nerves

A

Mycobacterium leprae —> Leprosy (Hansen disease)

cannot be grown in vitro

known as a “glove and stocking loss of sensation”

Reservoir: armadillos

Two types:

1) lepromatous - presents diffusely over the skin with leonine facies (lion like) . High bacterial load, low cell mediated immunity with humoral Th2 response. Can be lethal

Tx: clofazimine + dapsone + rifampin

2) Tuberculoid- few hypoesthetic hairless skin plaques characterized by high cell mediated immunity with a largely Th1 type immune response and low bacterial load

Tx: dapsone and rifampin

66
Q

Neisseria Gonococci vs Meningococci ?

A

Gonococci ferments Glucose
MeninGococci ferments Maltose and Glucose

Gonococci has no polysaccharide capsule. Use eryhromycin eye oitment to prevent neonatal blindness. Tx: ceftriazone ( + azithromycin or doxycycline, for possible chlamydial coinfection)

Meningococci has a polysaccharide capsule. There is a vaccine. Causes meningococcemia with petecial hemorrhages and gangrene of toes, meningitis, waterhouse friderichsen syndrome (adrenal insufficiency, fever, DIC, shock). Tx is ceftriaxone or penicillin G

67
Q

Cause of epiglottitis with a “cherry red” appearance and a thumb sign on xray

A

Haemophilus influenzae

nontypeable/unencapsulated is most common cause of mucosal infections

culture on chocolate agar, which contains factor V (NAD+) and X (hematin) for growth

Epiglottitis, thumb sign on lateral neck, meningitis, otitis media, and pneumonia

TX: amoxixillin +/- clavulanate for mucosal infections
Ceftriaxone for meningitis
Rifampin prophylaxis for close contact

68
Q

“whooping cough”

A

Bordetella pertussis

pertussis toxin disables Gi, adenylate cyclase toxin increases cAMP, and tracheal toxin

stages:

1) catarrhal- low grade fevers and Coryza (inflammation of mucous membranes of the nose)
2) Paroxysmal -intense cough followed by inspiratory whoop. Posttussive vomiting
3) Convalescent- gradual recovery of chronic cough

69
Q

Aerosol transmission from environmental water source habititat

A

Legionella pneumophila

Silver stain
Grow on charcoal yeast extract medium with iron and cysteine

Legionnaires disease - severe pneumonia which is often unilateral and lobar

Pontiac fever- mild flu like snydrome

Tx with macrolides or quinolone

70
Q

Pseudomonas aeruginosa

A

Aerobic, motile, non lactose fermenting

PSEUDOMONAS mnemonic
P-pneumonia
S-sepsis
E- Ecthyma gangrenosum  (rapidly progressive necrotic cutaneous lesion in immunocompromised patients)
U- UTI
D- Diabetes
O-Osteomyelitis
M-mucoid polysaccharide capsule
O-Otitis externa (swimmers ear)
N-Nosocomial infections (catheters etc)
A- Addicts (drug abusers)
S- skin infections (hot tub folliculitis, wound infection in burn victims)

Mucoid polysaccharide capsule can form biofilm –> Chronic pneumonia in CF

produces PEEPR:
Phospholipase C (degrades cell membrane)
Endotoxin (fever, shock)
Exotoxin A (inactivates EF-2)
Pigments pyoverdine and pyocyanin (blue green pigment)
Reactive oxygen species

Corneal ulcers in contact lens wearers

TX with CAMPFIRE drugs
Carbapenems
Aminoglycosides
Monobactams
Polymyxins 
Fluoroquinolones
ThIRD and fourth generation cephalosporins
Extended spectrum penicillins
71
Q

Pt presents with rose spots on abdomen, constipation followed by diarrhea, abdominal pain, fever

A

Salmonella typhi - Typhoid fever
H2S production
Flagella - salmon swim
Endotoxin and Vi capsule
High infectious dose required
Acid labile - inactivated by gastric acids
Carrier state with gallbladder colonization

GI sx due to invasion of M cells in peyer patches

give oral vaccine

72
Q

Pt has a pet turtle and is now experiencing diarrhea

A 
Salmonella spp. (Except typhi)
GI sx due to invasion of M cells in peyer patches
H2S production
Flagella (salmon swim)
Endotoxin
High infectous dose needed
Diarrhea can be bloody
No vaccine
poultry, eggs, pets, and turtles

antibiotics not indicated

73
Q

Shigella

A 
Invasion of M cells is key to pathogenicity
No H2S
No flagella
Endotoxin
Shiga toxin (enterooxin)
Low infectious dose required
Acid stable - resistant to gastric acids
Blood diary (bacillary dysentery)

(highest severity) S dysenteriae> S flexneri>S Boydii> S sonnei

74
Q

Pt ate pork and now has right lower abdominal pain

A

Yersinia enteroclitica

Pet feces, contaminated milk, or pork

acute diarrhea or pseudoappendicits (mesenteric adenitis and terminal ileitis)

75
Q

E. Coli

A

produces Beta galactosidase which breaks down lactose into glucose and galactose

fimbriae- cystitis and pyelonephritis (p-pili)
K capsule - pneumonia and neonatal meningitis
LPS endotoxin- septic shock

76
Q

EIEC

A

EnteroInvasive E coli

Invasive, dysentery, similar to shigella

77
Q

Travelers diarrhea

A

Enterotoxigenic E coli

produces heat labile and heat stable enterotoxins

No inflammation or invasion

Travelers diarrhea

78
Q

Child with diarrhea

A

EPEC: EnteroPathogenic E coli

adheres to apical surface, flattens villi, and prevents absorption

usually in children (think EPEC and pediatrics)

79
Q

pt presents with anemia, thrombocytopenia, and acute renal failure

A

EHEC: Enterohemorrhagic E coli

O157:H7

causes dystentery

Does not ferment sorbitol

shiga like toxin causes hemolytic uremic syndrome: triad of anemia, thrombocytopenia, and acute renal failure due to microthrombi forming on damaged endothelium –> mechanical hemolysis (with schistocytes on peripheral blood smear), platelet consumption, and decreased renal blood flow

80
Q

Bacteria known for lobar pneumonia in alcoholics and diabetics when aspirated. “currant jelly” sputum

A

Klebsiella

Very mucoid colonies caused by abundant polysaccharide capsules

Dark red “currant jelly” sputum (blood/mucus)

81
Q

Bacteria commonly associated with Guillian barre syndrome and reactive arthritis

A

campylobacter jejuni

comma or S shaped with polar flagella
Oxidase +
Grows at 42 C
Blood diarrhea

82
Q

Rice water diarrhea

A

Vibrio cholerae

Gram -, flagellated, coma shaped, oxidase +

grows on alkaline media

enterotoxin that permanently activates Gs which increases cAMP –> watery diarrhea

Sensitive to stomach acid/acid labile

requires large inoculum

83
Q

Duodenal peptic ulcers

A

Helicobacter pylori

curved, flagellated, gram - rod that is triple positive: catalase, oxidase, and urease

urease produces ammonia, creating an alkaline environment which helps H pylori survive in acidic mucosa

associated with gastric adenocarcinoma and MALT lymphoma

triple therapy: amoxicillin + clarithromycin + PPI

if penicillin allergy then replace amoxicillin with metronidazole

84
Q

Patient went hiking and now has a bullseye rash

A

Borrelia burgdorferi - lyme disease
Ixodes deer tick
Natural reservoir is the mouse
Spirochetes - borrelia is BIG

stage 1 - erythema migrans
stage 2 - early disseminated, carditis, AV block, bells palsy, migratory myalgias/transient arthritis
stage 3- late disseminated, encephalopathy and chronic arthitis

tx: doxycycline

amoxicillin and cefuroxime in pregnant women and children

85
Q

Found in water contaminated with animal urine

A

Leptospira interrogans
spirochete with a hook shape end

leptospirosis - flu like, myalgia in calves, jaundice, photophobia with conjunctival suffusion (erythema without exudate). Prevalent among surfers and in tropics

Weil disease- icterohemorrhagic leptospirosis. Severe form with jaundice and azotemia from liver and kidney dysfunction, fever, hemorrhage, and anemia

86
Q

Syphillis

A

spirochete Treponema pallidum

primary - painless chancre. Dark field microscopt. VDRL + in 80%

Secondary- Disseminated disease. Maculopapular rash (palms and soles), condylomata lata, dark field microscopy, confirm dx with FTA-ABS

Latent

Tertiary syphilis - Gummas (chronic granulomas), aortitis (vasa vasorum destruction), neurosyphilis (tabes dorsalis or general paresis), Argyll robertson pupil or prostitute pupil ( accommodates (constricts) but does not react (to light)). Pt presents with broad based ataxia and a + romberg sign, charcot joint (progressive degeneration of a weight bearing joint), stroke w/o HTN

87
Q

Congenital syphilis

A

facial abnormalities such as rhagases (linear scars at angle of mouth), snuffles (nasal discharge), saddle nose, notched (hutchinson ) teeth, mulberry molars

88
Q

VDRL false positives

A

test for syphilis

Pregnancy
Viral infection
Drugs
Rheumatic fever
Lupus and leprosy
89
Q

pt is started on antibiotics and starts to develop fever, chills, headache, myalgia

A

Jarisch Herxheimer rxn

flu like sx due to bacteria being killed and releasing toxins

90
Q

Pt presents with a fishy odor and vaginal discharge

A

Gardnerella vaginalis

“I dont have a clue why I smell fish int he vagina garden”

Bacterial vaginosis
Gray vaginal discharge
Fishy smell
Nonpainful
Clue cells : vaginal epithelial cells covered with Gardnerella have stippled appearance along outer margin

amine whiff test- mixing discharge with 10% KOH enhances fishy odor

tx with metronidazole or clindamycin

91
Q

Chlamydia

A

cell wall lacks peptidoglycan and tehrefore rendering beta lactams anitbiotics ineffective

Elementary body (small and dense) is infectious and enters cell via endocytosis

Then transforms into reticulate body which replicates in cell by fission

reorganizes into elementary bodies

chlamydia trachomatis causes reactive arthritis (reiter syndrome), neonatal and follicular adult conjunctivitis, nongonococcal urethritis, and PID

tx: azithromycin or doxycycline ( + ceftriazone for possible gonorrhea)

92
Q

Chlamydia trachomatis sertypes

A

ABC : Africa, blindness due to follicular conjunctivitis, and chronic infection

D-K: everything else. urethritis/PID, ectopic pregnancy, neonatal pneumonia with staccato cough with eosinophilia, neonatal conjunctivitis

L1,L2,L3: lymphogranuloma venereum- small painless ulcers on genitals –> swollen painful inguinal lymph nodes that ulcerate (buboes). tx with doxycycline

93
Q

Cat scratch dz

A

Bartonella spp

bacillary angiomatosis

94
Q

Relapsing fever

A

Borrelia recurrentis

spread by louse

95
Q

Plague

A

Yersinia pestis

Fleas from rats and prairie dogs

96
Q

Brucellosis/undulant fever

A

unpasteurized dairy

Brucella spp

97
Q

Pt presents with a rash that started on wrists and ankles and has now spread to her trunk, palms, and soles. She also complains of a headache and a fever.

A

Rocky mountain spotted fever

Rickettsia rickettsii, vector is the dermacenter dog tick

South atlantic states (i.e. N carolina)

98
Q

Pt developed a rash that started centrally and spreads out. It has spared the palms and soles

A

Endemic (fleas) - R typhi
Epidemic (human body lous) - R prowazekii

Typhus

99
Q

Ehrlichiosis

A

Ehrlichia
Vector is a tick
Monocytes with morulae (mulberry like inclusions) in cytoplasm

100
Q

Anaplasmosis

A

Anaplasma
Vector is a tick
Granulocytes with morulae in cytoplasm

101
Q

Q fever

A

coxiella burnetii

spores are inhaled as aerosols from cattle/sheep amniotic fluid

presents as pneumonia

common cause of culture - endocarditis

102
Q

Mycoplasma pneumoniae

A

atypical “walking” pneumonia (insidious onset, headache, nonproductive cough, patchy or diffuse interstitial infiltrate)

cold agglutinins (IgM), Eaton agar

bacterial membrane contains sterols for stability

pt < 30 yo, military recruits and prisons

tx: macrolides, doxycycline, or fluoroquinolones. No penicillin because mycoplasma lack a cell wall

103
Q

Common cause of pneumonia in neonates

A

Group B streptococci

E coli

104
Q

common cause of pneumonia in 4 wk-18 yr

A 
RSV
Mycoplasma
C trachomatis (infant - 3 yr)
C pneumo (school aged)
S pneumo
105
Q

Glucose levels drop in ______ meningitis

A

bacterial or fungal

106
Q

What infections most commonly cause brain abscess

A

Strep and staph aureus

107
Q

Most common bug to cause osteomyelitis

A

Staph aureus

note: MRI is best for acute infections and fetailing anatomic involvement. Xrays are for later/chronic

108
Q

TX for bacterial vaginosis and trichomonas vaginitis

A

Metronidazole

109
Q

Chancroids

A

painful genital ulcer with exudate and inguinal adenopathy

Haemophilus ducreyi ( its so painful you “do cry”)

110
Q

Granuloma Inguinale (Donovanosis)

A

Painless, beefy red ulcer that bleeds readily on contact

klebsiella (calymmatobacterium) granulomatis

cytoplasmic donovan bodies (bipolar staining) seen on microscopy

111
Q

Pt was dx with PID that was left untreated. She now presents with infection and inflammation of the liver capsule and “violin string” adhesions of peritoneum to the liver

A

PID can lead to perihepatitis (Fitz Hugh Curtis syndrome)

112
Q

Urinary catheterization infections

A

infections of your PEcKer

Proteus spp
E coli
Klebsiella

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