Micro Bacteria Flashcards Preview

► Med 11 - USMLE 1 > Micro Bacteria > Flashcards

Flashcards in Micro Bacteria Deck (117):
1

Gram+ Cocci lab algorithm

Cocci --> Catalase test
Catalase -: Streptococcus
Catalase +: Staph
Staph --> Coagulase test
Coagulase +: S aureus
Coagulase -: Do Novobiocin test
"NO StRESs at the staph retreat"
Novobiocin sensitive: S epidermidis
Novobiocin resistant: S saprophyticus

2

Gram+ rods

Clostridium (anaerobe)
Corynebacterium
Listeria
Bacillus (aerobe)
Mycobacterium (acid fast)

3

Gram+ with branching filaments

Anaerobe, not acid fast: Actinomyces
Aerobe, acid fast: Nocardia

4

Streptococcus algorithm

Hemolysis test
Partial hemolysis --> green on blood agar--> α
Complete hemolysis --> clear on blood agar --> β
No hemolysis on blood agar --> γ

5

α Hemolytic Strep Algorithm

"OVRPS"
Capsule, +Quellung, Optochin sensitive --> Strep pneumoniae
No capsule, Optochin resistant --> Viridans streptococci (S mutans)

6

β Hemolytic Strep Algorithm

"B-BRAS"
Group A: Bacitracin sensitive --> S pyogenes
Group B: Bacitracin resistent --> S agalactiae

7

γ Hemolytic Strep Algorithm

Group D (Enterococcus): Growth in bile and 6.5% NaCl (E faecalis)
Nonenterococcus: Growth in bile, not 6.5% NaCl (S bovis)

8

β-Hemolytic Bacteria

Staphlococcus aureus (catalase+, coagulase+)
Streptococcus pyogenes (GAS: Catalase-, Bacitracin sensitive)
Streptococcus agalactiae (GBS: Catalase-, Bacitracin resistent)
Listeria Monocytogenes (tumbling motility, meningitis in newborns, unpasteurized milk)

9

Staphyloccus aureus
Gram, Shape, Arrangement, Marker
Weapon
Diseases it causes?

Gram+ Cocci in Clusters, Catalase+, Coagulase+
Protein A binds FcIgG and inhibits complement fixation and phagocytosis
TSST --> fever, vomiting, rash, desquamation, shock, end organ failure
Skin infection, Organ abscess (coagulase forms fibrin clot around self), Pneumonia, Endocarditis, Osteomyelitis, Food poisoning (preformed toxins), TSS, Scalded skin syndrome (exfoliative toxin)

10

MRSA
What is it?
Resistent to...

Methicillin Resistent Staph Aureus
Resistent to β-lactams because of altered penicillin binding protein

11

Staphylococcus epidermidis
Where is it normally located
Contaminates what?
What does it infect?

Part of normal skin flora
Contaminates blood cultures
Infects prosthetic devices and IV catheters by producing adherent biofilms

12

Streptococcus pneumoniae
Gram, Shape, Arrangement
Weapons
Markers
Most common cause of...
Presentation

Gram+, Lancet Shaped, Diplococci
Encapsulated, IgA protease
α hemolytic, Optochin sensitive
"MOPS are Most OPtochin Sensitive"
Meningitis, Otitis media (in children), Pneumonia, Sinusitis
Rusty sputum, sepsis in sickle cell anemia and splenectomy

13

Viridans Group Streptococci
Markers
Where are they normally
What do they cause?
What does it adhere to?

α hemolytic, Optochin Resistent, Produces Dextran from Sucrose
Normal flora of oropharynx
Dental caries (S mutans) and Subacute bacterial endocarditis (S sanguis) - stick to prosthetic valve via glycocalyx
Adheres to Fibrin-Platelet Aggregates

14

Streptococcus pyogenes
Markers
Versions w/ diseases
Diagnosis
Significant protein marker

Gram+ Cocci, β-Hemolytic, bacitracin sensitive
Pyogenic: pharyngitis, cellulitis, impetigo
Toxigenic: scarlet fever, TSLS, Necrotizing fasciitis
Immunologic: Rheumatic fever, acute glomerulonephritis
ASO titers
M protein enhances host defense but gives rise to rheumatic fever

15

Diagnosis of RF
What causes it?

GAS
"JONES"
Joints - polyaarthritis
Carditis
Nodules (subcutaneous)
Erythema marginatum
Sydenham's chorea

16

Scarlet Fever Presentation

Scarlet rash sparing face, Strawberry (scarlet) tongue, Scarlet throat

17

What GAS presentations can lead to other problems?

Pharyngitis --> RF and Glomerulonephritis
Impetigo more commonly precedes glomerulonephritis than pharyngitis

18

Streptococcus agalacgtiae
Markers
What does it produce?
Colonizes where?
What diseases does it cause? In whom?
Screen
Treatment

"GBS: B is for babies"
Gram+ Cocci, β-Hemolytic, bacitracin resistent, Hippurate test +
Produces CAMP factor which enlarges area of hemolysis formed by S aureus
Vagina
Pneumonia, Meningitis, and Sepsis in babies
Screen pregnant women at 35-37 weeks
Pt's with + cultures receive intrapartum penicillin prophylaxis

19

Enterococcus
Names
Markers
Where are they normally?
Resistant to?
What do they cause?
Bad version?

GDS: E. faecalis and E. faecium
Gram+ cocci Non-hemolytic and growth in bile and 6.5% NaCl
Normally in colonic flora
Penicillin G resistent
UTI, Biliary tract infections, Subacute endocarditis
VRE important in nosocomial infection

20

Lancefield Grouping based on?

Difference in C carbohydrate in cell wall

21

Streptococcus bovis
Markers
Where does it colonize
What can it cause?

GDS: S bovis
Gram+ cocci Non-hemolytic and growth in bile but not 6.5% NaCl
Colonizes the gut
Bacteremia and subacute endocarditis in colon cancer patients

22

GDS

S bovis, E. faecalis, E. faecium

23

Corynebacterium diphtheriae
Markers
Plating
Toxin test?
Stains
Diseases it causes? How?
Symptoms
Vaccine

Gram+ rods with metachromatic (blue and red) granules
Black colonies on Cystine-Tellurite agar
Elek's test for toxins
+ Aniline dyes
Diphtheria via exotoxin encoded by β prophage. Inhibits protein synthesis by ADP-ribosylation of EF2
Pseudomembranous pharyngitis (gray-white membrane), lymphadenopathy, myocarditis, arrhythmias
Toxoid vaccine prevents diphtheria

24

Spores
What do have in their core?
How do you kill spores?

Dipicolinic acid in the core
Autoclave @ 121 degrees C for 15 minutes

25

Clostridia
Markers
What do they form?
Types

Gram+ rods that are obligate anaerobes. Spore forming
Tetani, Botulinum, Perfringens, Difficile

26

Clostridium tetani
Markers
Toxin
Presentation

Gram+ rods that are obligate anaerobes. Spore forming
Tetanospasmin is an exotoxin. Cleaves SNARE protein required for NT release of GABA and Gly neurons (Renshaw cells in spinal cord)
Muscle rigidity, lock jaw, Risus sardonicus

27

Clostridium botulinum
Markers
Toxin
Presentation

Gram+ rods that are obligate anaerobes. Spore forming
Botulinum toxin
Cleaves SNARE protein required for NT release of ACh from neurons
Baby who ate honey has Flaccid paralysis (floppy baby)

28

Clostridium perfringens
Markers
Toxin
Presentation

Gram+ rods that are obligate anaerobes. Spore forming
Alpha toxin (lecithinase)
Phospholipase that degrades tissues and cell membranes
Degradation of phospholipid C --> myonecrosis (gas gangrene) and hemolysis (double zone of hemolysis on blood agar)
Gas Gangrenous Leg

29

Clostridium difficile
Markers
Toxin
Presentation
Diagnosis
Treatment

Gram+ rods that are obligate anaerobes. Spore forming
Toxin A (enterotoxin) binds brush border of gut
Toxin B (cytotoxin) destroys cytoskeletal structure of enterocytes causing pseudomembranous colitis
Diarrhea after antibiotic use (clindamycin or ampicillin)
Detection of toxin in stool
Metronidazole or oral vancomycin

30

Anthrax
Markers
What is special about it?
What does it produce?
Types

Gram+ spore forming rod
Only bacteria with polypeptide capsule (with D-glutamate)
Antrax toxin
Cutaneous vs Pulmonary

31

Cutaneous Anthrax

Contact --> black eschar (painless ulcer); can progress to bacteremia and death
Black skin lesion - black eschar (necrosis) surrounded by edematous ring
Caused by Lethal factor and Edema factor (Mimics AC and increases cAMP)

32

Pulmonary Anthrax

Inhalation of spores --> flu-like symptoms that rapidly progresses to fever, pulmonary hemorrhage, mediastinitis, and shock

33

Woolsorters' Disease

Inhalation of Anthrax spores from contaminated wool

34

Bacillus cereus
Markers
How is it contracted
Types with presentation

Gram+ aerobic rods
Food poisoning. Spores survive cooking rice and keeping it warm results in germination of spores and enterotoxin formation
Emetic type: Rice and pasta. Nausea and vomiting for 1-5 hours caused by cereulide (a preformed toxin)
Diarrheal type causes watery non-bloody diarrhea and GI pain for 8-18 hours

35

Listeria Monocytogenes
Markers
Where can it live?
How is it acquired?
How do they travel?

Gram+ rods
Facultative intracellular microbe
Ingestion of unpasteurized milk/cheese or deli meats. Vaginal transmission during birth
Forms actin rockets to move from cell to cell with characteristic tumbling motility

36

Listeria Monocytogenes
Diseases caused by them?
Treatment

Amnionitis, Septicemia, and Spontaneous abortion in pregnant women
Granulomatosis infantiseptica, Neonatal meningitis
Meningitis in immunocompromised pts
Mild gastroenteritis in health individuals
Gastroenteritis is self limiting
Ampicillin for infants, immunocompromised and elderly

37

Actinomyces
Markers
Air?
Acid Fast?
Where is it found?
Presentation
Treatment

Gram+ branching filaments
Anaerobic
Not Acid Fast
Normal oral flora
Oral/facial abscesses that drain through sinus tracts forming yellow sulfur granules
Penicillin

38

Nocardia
Markers
Air?
Acid Fast?
Where is it found?
Presentation
Treatment

Gram+ branching filaments
Aerobe
Acid Fast
Soil
Pulmonary infections in immunocompromised
Cutaneous infections after trauma in normals
Sulfonamides

39

PPD+ vs PPD-

+: Current infection, Past exposure, BCG vaccinated
-: No infection, anergic (steroids, malnutrition, immunocompromised), or Sarcoidosis

40

Mycobacteria
Stain
Names

Acid Fast
Tuberculosis
Kansaii (pulmonary TB-like symptoms)
Avium-Intracellulare (disseminated nonTB disease in AIDS resistant to multiple drugs. Treat prophylactically with azithromycin)
Leprae

41

Mycobacterium tuberculosis
Symptoms
Weapons
Histo

Fever, Night sweats, Wt loss, Hemoptysis
Cord Factor: inhibits macrophage maturation and induces release of TNFα
Sulfatides (surface glycolipids) inhibit phagosysosomal fusion
Caseating granuloma w/ multinuclear Langhan's giant cells

42

Primary TB
Who is at risk?
Course

Non immune host (usually a child)
Hilar nodes + Ghon focus (usually in mid zone of lung) = Ghon Complex
Heals by fibrosis --> immunity and hypersensitivity --> Tuberculin+
Progressive disease
Bacteremia --> miliary TB
Preallergic lymphatic or hematogenous dissemination --> dormancy in several organs --> reactivation in adult life

43

Secondary TB
Who is at risk?
Initial Course
Reactivation

Partially immune hypersensitized host (adult)
Fibrocaseous cavitary lesion usually in upper lobes
Reactivation in the lungs
CNS (parenchymal tuberculoma or meningitis)
Vertebral body (Pott's Disease)
Lymphadenitis, Renal, GI

44

Mycobacterium leparae
Temperatures
Growth in vitro
Reservoir in US
Forms
Treatment

Likes cool temps: infects skin, superficial nerves (glove and stocking loss of sensation)
Cannot be grown in vitro
Armadillos
Lepromatuous vs Tuberculoid
Dapsone + Rifampin

45

Lepromatous Leprosy
Presentation
Communicable?
Host response?
Treatment

Presents diffusely over skin
Communicable
Low cell-mediated immunity with a humoral Th2 response
Dapsone + Rifampin + Clofazimine for 2-5 years

46

Tuberculoid Leprosy
Presentation
Host response?
Treatment

Limited to a few hypoesthetic hairless skin plaques
High cell-mediated immunity with Th1 cell response
Dapsone + Rifampin for 6 months

47

Gram- algorithm

Oxidase+, comma shaped: Campylobacter jejuni or Vibrio cholerae
Diplococci --> Maltose test
M+: Neisseria meningitidis. M-: N. gonorrhoeae
Coccoid rods --> Haemophilus influenzae, Pasturella, Brucella, Bordetella pertussis
Rods --> Lactose fermentation test
L+: Klebsiella, E coli, Enterobacter
L-: Oxidase test
O+: Pseudomonas, H pylori
O-: Shigella, Salmonella, Proteus

48

Lactose-fermenting enteric bacteria
Test
Enzyme
Examples

"test with MacConKEES agar"
Pink colonies on MacConkey's agar
Purple/black colonies on EMB
E coli grows with purple colonies with green sheen
E coli produces β-galactosidase breaks lactose into glucose and galactose
Citrobacter, Klebsiella, E coli, Enterobacter, Serratia

49

Gram- and penicillin

Gram- outer membrane layer inhibits entry of penicillinG and vancomycin
May be susceptible to penicillin derivatives (ampicillin, amoxicillin)

50

Algorithm for Lactose fermenting, Gram- rods

Fast fermenters: Klebsiella, E coli, Enterobacter
Slow fermenters: Citobacter, Serratia

51

Algorithm for non-Lactose fermenting, Gram- rods

Do Oxidase Test
Oxidase+: Pseudomonas, H pylori
Oxidase-: Shigella, Salmonella, Proteus

52

Algorithm for oxidase+, Comma shaped Gram-

Grows @ 42: Campylobacter jejuni
Grows in alkaline media: Vibrio Cholerae

53

Neisseria
Markers
Fermentation?
Product?
Kinds?

Gram- diplococci
Both ferment glucose
Produce IgA proteases
Gonococci vs Meningococci

54

Neisseria Gonococci
Capsule
Fermentation
Vaccine
Transmission
Residence?

No polysaccharide capsule
Only Glucose fermentation
No vaccine (due to antigenic variation of pilus proteins)
Sexual transmission
Polymorphonuclear leukocytes

55

Neisseria Gonococci
Disease it causes?
Treatment

Gonorrhea, Septic arthritis, Neonatal conjunctivitis, PID, Fitz-Hugh-Curtis syndrome
Ceftriaxone + (azithromycin or doxycycline) for possible chlamydia coinfection

56

Neisseria Meningococci
Capsule
Fermentation
Vaccine
Transmission

Polysaccharide capsule
Ferments Glucose and Maltose
Vaccine (none for type B)
Respiratory and oral secretions

57

Neisseria Meningococci
Disease it causes?
Prophylaxis
Treatment

Meningococcemia, Meningitis, Waterhouse-Friderichsen syndrome
Rifampin, Ciprofloxacin, Ceftriaxone
Ceftriaxone or PenicillinG

58

Haemophilus influenzae
Markers
Transmission
Most invasive kind?
Non-typeable strains?
Weapon
Vaccine

Gram- coccoid rods
Aerosol transmission
Most invasive is capsular type B
Cause mucosal infections (otitis media, conjunctivitis, bronchitis)
IgA protease
Vaccine contains B capsular polysaccharide (polyribosylribitol phosphate) conjugated to diphtheria toxoid and other proteins. Give @ 2-18 months

59

Haemophilus influenzae
Growth
What diseases does it cause?
Prophylaxis
Treatment

"When child has the flu, mom goes to V and X store to buy some chocolate"
Chocolate agar requires V (NAD) and X (hematin). Can also grow with S aureus (provides V)
"haEMOPhilus"
Causes Epiglottitis (cherry red in children), Meningitis, Otitis media, Pneumonia
Rifampin
Ceftriaxone

60

Legionella pneumophila
Markers
Stains
Growth
Diagnosis, Labs
Transmission
Diseases caused by it?
Treatment

Gram- rods but stain poorly. Use Silver stain
"French Legionnaire with Silver helmet, sitting around a Charcoal fire with his Iron dagger. He's no Sissy (cysteine)"
Charcoal yeast extract with iron and cysteine
Ag in urine. Hyponatremia
Aerosol transmission from water source. No person-to-perosn
Legionnaires disease, Pontiac fever
Macrolide or Quinolone

61

Legionnaires disease
Caused by...
Presentation

Legionella pneumophila
Severe pneumonia, Fever, GI, CNS symptoms

62

Pontiac fever
Caused by...
Presentation

Legionella pneumophila
Mild flu-like symptoms

63

Pseudomonas aeruginosa
Markers
Gross
Source
Weapons
Classic pt that gets it?

Gram- rod. Aerobic ("think AERuginosa - Aerobic"). Non-lactose fermenting, Oxidase+
Produces pyocyanin (blue-green) pigment. Grape-like odor
Water source
Endotoxin (fever, shock), Exotoxin A (inactivates EF2)
Burn victims, CF pt

64

Pseudomonas aeruginosa
Presentation
Treatment

"PSEUDOmonas"
Wound and burn infections. Hot tub folliculitis. Malignant Otitis externa in diabetics.
Pneumonia (in CF pt), Sepsis (black lesions on skin), External otitis (swimmers ear), UTI, Drug use, and Diabetic Osteomyelitis
Aminoglycoside + extended spectrum penicillin (piperacillin, ticarcillin)

65

E coli
Weapons
Types

Fimbriae (cystitis and pyelonephritis)
K capsule (pneumonia, neonatal meningitis)
LPS endotoxin (septic shock)
EIEC, ETEC, EPEC, EHEC

66

EIEC
What does it invade?
What does it cause?
Presentation

"I = Invades Intestines"
Invades intestinal mucosa
Necrosis and inflammation
Presents like Shigella

67

ETEC
What does it cause?
Toxin
Course

"T = Travelers"
Travelers Diarrhea (watery)
Labile toxin, Stable toxin
No inflammation or invasion

68

EPEC
Presentation
Toxins
What does it do?

"P = Pediatrics"
Diarrhea in children
No toxin produced
adheres to apical surface, flattens villi, and prevents absorption

69

EHEC
Most common serotype
Markers
PathoPhys
What does it lead to?
Toxin
Presentation

O157:H7
Does not ferment sorbitol (distinguish it from other E coli)
Swells endothelium --> narrowed lumen --> hemolysis, reduced renal blood flow. Damaged endothelium consumes platelets
Hemolytic Uremic Syndrome: Anemia, Thrombocytopenia, Acute Renal Failure
Shiga-like toxin. Dysentery (toxin alone causes necrosis and inflammation)

70

Klebsiella
Markers
Where is it normally?
What does it cause?
Classic presentation

"4As"
Aspiration pneumonia, Abscess in lungs and liver, Alcoholics, diAbetics
Gram- Rods. Lactose fermenter
Intestinal flora
Lobal pneumonia in alcoholics and diabetics when aspirated. Nosocomial UTIs
Red currant jelly sputum from polysaccharide capsule

71

Salmonella
Markers, Flagella, Dissemination
Reservoirs, Produces...
Antibiotic, Invasion?
Host response?
Presentation

Gram- rods. NonLactose fermenting Oxidase-
Flagella+, Disseminated hematogenously
Many animal reservoirs. Produces Hydrogen sulfide
Antibiotics prolong symptoms
Invades intestinal mucosa. Causes Monocytic response
Can cause bloody diarrhea

72

Shigella
Markers, Flagella, Dissemination
Reservoirs, Produces...
Antibiotic, Invasion?
Host response?
Presentation

Gram- rods. NonLactose fermenting Oxidase-
Flagella-. Cell-to-cell transmission. no hematogenous spread
Human and primate reservoirs. Does not produces Hydrogen sulfide
Antibiotics shorten excretion of organisms in feces
Invades intestinal mucosa. Causes PMN infiltration
Often cause bloody diarrhea

73

Salmonella Typhi
What does it cause?
Found in...
Presentation
Carrier state?

Typhoid fever
Only in humans
Rose spots on the abdomen, fever, headache, diarrhea
Can remain in gallbladder and causes carrier state

74

Campylobacter jejuni
Markers
Presentation
Transmission
What follows it?

Gram- comma shaped oxidase+ that grows at 42 degs C
Bloody diarrhea in children
Fecal-oral transmission
Guillain Barre Syndrome and Reactive Arthritis

75

Vibrio Cholerae
Markers
MoA
Presentation
Treatment

Gram- comma shaped oxidase+ that grows in alkaline media
Produces toxin that permanently activates Gs --> ↑cAMP
Rice-water diarrhea endemic in developing countries
Oral rehydration

76

Yersinia enterocolitica
Markers
Transmission
Presentation

Gram- coccobacillus
Pet feces, contaminated milk, pork
Mesenteric adenitis that mimics Crohn's or Appendicitis

77

Helicobacter pylori
Markers
What does it cause?
Increases risk for...
MoA
Treatment

Gram- rods. Doesn't ferment lactose. Oxidase+, Urease+ (breath test)
Gastritis and duodenal ulcers
Risk factor for Peptic Ulcers, Gastric Adenocarcinoma, Lymphoma
Creates alkaline environment
PPI, Clarithromycin, Amoxicillin, or Metronidazole

78

Spirochetes
Shape
Names
Visualization

Spiral shaped bacteria with axial filaments
"BLT"
Borrelia (big size), Leptospira, Treponema
Only Borrelia can be visualized using aniline dyes (Wright's or Giemsa stain) in light microscopy
Treponema can be visualized by dark-field microscopy

79

Leptospira Interrogans
Where is it found?
Presentation
Who gets it?

Water contaminated with animal urine
Leptospirosis: flu-like symptoms Jaundice, Photophobia w/ conjunctivitis
Surfers and in tropics (Hawaii)

80

Weil's Disease

Icterohemorrhagic leptospirosis: Severe jaundice and Azotemia from liver and kidney dysfunction, Fever, Hemorrhage and anemia

81

Lyme Disease
Caused by...
Visualization
Transmission
Reservoir
Location
Presentation
Treatment

Borrelia burgdorferi
Aniline dyes (Wright's or Giemsa stain) in light microscopy
Tick Ixodes
Mouse
NE USA
"FAKE a key lyme pie"
Facial nerve palsy (bilaterally), Arthritis, Cardiac Block, Erythema Migrans
Doxycycline, Ceftriaxone

82

Stages of Lyme Disease

1: Erythema chronicum migrans (bull's eye) and flu like symptoms
2: Neurologic (facial nerve palsy) and cardiac (AV block) manifestations
3: Musculoskeletal (chronic monoarthritis and migratory polyarthritis), Neurological (encephalopathy and polyneuropathy), and cutaneous manifestations

83

Syphilis
Caused by...
Visualization
Treatment

Spirochete Treponema pallidum
Dark field microscopy
PenicillinG

84

Primary Syphilis
Presentation
Diagnosis

Localized disease presenting with painless chancre (with Treponema inside)
Screen with VDRL and confirm with FTA-ABS

85

Secondary Syphilis
Presentation
Diagnosis

Disseminated disease w/ constitutional symptoms, maculopapular rash (palms and soles), Condylomata lata (with Treponema inside)
Screen with VDRL and confirm with FTA-ABS

86

Tertiary Syphilis
What does it cause?
Presentation
Diagnosis

Gummas (chronic granulomas), Aortitis (vasa vasorum destruction), Neurosyphilis (tabes dorsalis), Argyll Robertson pupil
Broad-based ataxia, +Romberg, Charcot joint, Stroke w/o HTN
Test spinal fluid with VDRL

87

Congenital Syphilis
Presentation
When does it happen?

Saber shins, Saddle nose, CNVIII deafness, Hutchinson's teeth, Mulberry molars
After first trimester

88

Argyll Robertson Pupil

Pupils constrict with accommodation but is not reactive to light
Associated with tertiary syphilis
"Prostitute's pupil" accommodates but doesn't react

89

VDRL
What is it?
False+

VDRL detects non-specific antibodies that react with beef cardiolipin
"VDRL"
Viruses (mono, hepatitis), Drugs, RF, Lupus, Leprosy

90

Jarisch-Herxheimer Reaction

Flu like syndrome in Syphilis pt immediately after antibiotics are started due to killed bacteria releasing pyrogens

91

Cat Scratch

Cat scratch disease from Bartonella Spp

92

Louse

Recurrent fevers from Borrelia recurrentis
Epidemic Typhus from Rickettsia Prowazekii

93

Unpasteurized dairy

Brucellosis/Undulant fever from Brucella Spp

94

Parrots and other birds

Psittacosis from Chlamydophila psittaci

95

Cattle/sheep amniotic fluid

Q fever from Coxiella burnetii

96

Lone Star Tick

Ehrlichiosis from Ehrlichia chaffeensis

97

Ticks, Rabbits, Deer Fly

Tularemia from Francisella tularensis

98

Animal bite, cats or dogs

Cellulitis, Osteomyelitis from Pastuerella multocida

99

Dermacentor tick bite

Rocky Mountain Spotted Fever from Rickettsia Rickettsii

100

Fleas

Endemic typhus from Rickettsia typhi
Plague from Yersinia pestis

101

Gardnerella vaginalis
Markers
Presentation
Associated w/...
Histo
Treatment

"I don't have a CLUE why I smell FISH in the VAGINA"
Pleomorphic gram variable rods
Vaginosis: gray vaginal discharge with fishy smell. Non painful
Associated with sexual activity but not an STD
Clue cell or vaginal epithelial cells covered with bacteria
Metronidazole

102

Bacterial vaginosis

Overgrowth of certain bacteria in the vagina

103

Rickettsia rickettsii
Gram
Where do they live
Distribution
What does it cause?
Presentation

Gram-
Obligate intracellular that need CoA and NAD
All over USA
Rocky Mountain Spotted Fever
Rash that starts at wrists and ankles

104

Rickettsia
Markers
Where do they live?

Gram-. rod-to-coccoid shaped
Obligate intracellular organisms

105

Rickettsia typhi
What kind of outbreak?
Vector
Presentation

Endemic
Fleas
Headache, fever, rash on trunk

106

Rickettsia prowazekii
What kind of outbreak?
Vector
Presentation

Epidemic
Human body louse
Rash starts centrally and spreads out sparing soles and palms

107

Palm and Sole Rash

"CARS driving with your palms and soles"
Coxsackievirus A, Rocky Mountain Spotted Fever, Secondary Syphilis

108

Ehrlichiosis
Caused by...
Presentation
Vector
Histo

Ehrlichia (a kind of rickettsia)
No rash
Ticks
Monocytes with morula (berry-like inclusions) in cytoplasm

109

Anaplasmosis
Caused by...
Presentation
Vector
Histo

Anaplasma (a kind of rickettsia)
No rash
Tick
Granulocytes with morula in cytoplasm

110

Q fever
Vectors
What causes it?
Presentation

Tick feces and cattle placenta release spores that are inhaled by aerosols as spores. No arthropod vectors
Coxiella burnetii (closely related to rickettsia - obligate intracellular parasite)
Presents as pneumonia

111

Chlamydiae
Markers
Cell wall
What kind of infections
Lab diagnosis?
Forms
Treatment

Gram- Obligate intracellular parasite
Lacks Muramic Acid and Peptidoglycans
Mucosal infections
Cytoplasmic inclusions seen on Giemsa or Fluorescent Ab-stained smear
Elementary body (small, dense) is infectious and Enters cell via Endocytosis
Reticulate body Replicates in cell by fission. Form seen on tissue culture
Azithromycin (favored) or doxycycline

112

Chlamydia trachomatis

Causes reactive arthritis, conjunctivitis, non-gonococcal urethritis, and PID

113

Chlamydia pneumoniae and Chlamydia psittaci
Presentation
Transmission
Reservoir

Atypical pneumonia
Aerosol.
Psittaci notable for avian reservoir

114

Chlamydia trachomatis
Serotypes

A,B,C: Africa, Blindness (follicular conjunctivitis), Chronic infections
D-K: Urethritis/PID, Ectopic pregnancy, Neonatal pneumonia (staccato cough), neonatal conjuntivitis
Neonatal acquired by passage through birth canal
L1,L2,L3: Lymphogranuloma venereum

115

Mycoplasma pneumoniae
Markers
Cell wall
Growth
Titer

No Gram stain. No cell wall, Membrane contains sterols for stability
Eaton's agar
Cold agglutinins (IgM) which can agglutinate or lyse RBCs

116

Mycoplasma pneumoniae
Presentation
XR
Outbreaks

Walking pneumonia: insidious onset, headache, non-productive cough, diffuse interstitial infiltrate
XR looks worse than pt
Outbreaks in military recruits and prisons. Pts under 30

117

Bordetella pertussis
Markers
Presentation
Growth
Treatment

Gram - coccobacillus
Whooping cough (staccato cough with deep inspirations)
Bordet-Gengou Agar
Pre whooping cough: Erythromycin
Post whooping cough: Supportive care