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Flashcards in New Material For Midterm Deck (111):
1

Bordetella pertussis

Gram -
Coccobacilli
Fastidious: nicotinamide and charcoal (bordet gengou agar)
Whooping cough
Aerosol transmission

2

Bordetella pertussis virulence factors

Filamentous hemagglutinin- biofilm and stops Th1 response
Pertactin pili
Tracheal cytotoxin
Adenylate cyclase toxin AB
Pertussis toxin AB

3

Stages of pertussis

Catarrhal: mucoid rhinorrhea treat with Ab
Paroxysmal: 2-4 weeks of violent coughing
Convalescent: 3-4 weeks with secondary infections

4

Haemophilus ssp.

Gram -
Coccobacilli
Fastidious: blood agar as satellite of s. aureus or on chocolate
Haemophilus influenza type B or haemophilus ducreyi

5

Haemophilus virulence factors

Polysaccharide capsule
Pili
No exotoxins
Lipooligosaccharides (LOS) endotoxins major part in meningitis

6

Haemophilus diseases

Child age meningitis with capsule and LOS
Epiglottitis
Otitis media by no encapsulated type
Conjunctivitis

7

Haemophilus treatment

Azithromycin, amoxicillin clavulanate, trimethoprim sulfamethoxazole
Rifampin for prophylaxis
Vaccine: tetanus toxoid conjugate and meningococcal surface protein

8

Haemophilus ducreyi

Chancroid genital lesions
Pili
DsrA prevents complement activation
No protection with vaccine
Azythromycin, erythromycin or ciprofloxin

9

Legionella

Gram -
Dieterle silver stain
Very fastidious
Legionella pneumophila
No human to human spread

10

Legionnaires disease

Pneumonia, cough, and fever
2-14 days
You want to isolate the organism
Hospitalization and antibiotics
No immunity

11

Pontiac fever

Flu like but no pneumonia
2-3 days
Don't isolate organism
No hospitalization and has spontaneous resolution

12

Legionella pneumophila pathogenesis

Facultative Intracelular pathogen of macrophages and dendritic cells
Endotoxins inflammatory responses
Clearance requires CD4 activation of macrophages

13

Legionella virulence factors

LPS
OMO MIP macrophage invasion potentiator that binds a complement receptor on macrophages
Secretion apparatus dot/ICm system type IV allows injection of host molecules (also prevents fusion of Legionella vacuole with endosomes)
SdhA survival in macrophages
SidJ and AnkB

14

Listeria monocytogenes

Gram +
Coccoid
Facultative anaerobes
Cat +
B-hemolytic
Associated with livestock

15

Listeria

Nausea, abdominal pain, diarrhea, fever
Vertical transmission
Antibiotic susceptible
Facultative Intracelular pathogen: enterocytes, fibroblasts, endothelial cells and hepatocytes
T cell mediated immunity

16

Listeria virulence factors

Internalin
PLC cytolysins cuts skin (cuts lipids)
Listeriolysin O: oxidative sensitive and allows for escape from the phagosomal
ActA and VASP: polymerize actin

17

Campylobacter

Gram - S-shaped rods
Microaerophilic
Supplement CO2
CAMP media fastidious
Nitrate reductase, catalase, and oxidase +
Fecal oral with highest rates during the summer
Resistant to vanco, trimethoprim, and polymyxin B

18

Campylobacter jejuni

Acute gastroenteritis
Guillian Barre syndrome

19

Campylobacter fetus

Septicemia in newborns

20

Campylobacter virulence factors

Acid tolerant
LPS: molecular mimicry with peripheral nerve myelin
Flagella
C. Jejuni adhere to endothelial/epithelial cells
BLOODY DIARRHEA

21

Helicobacter pylori

Gram -
Spiral rods
Microaerophilic
Fecal oral

22

Helicobacter pylori diseases

Chronic gastritis
Peptic ulcer disease
Gastric adenocarcinoma
Gastric mucosal associated lymphoid tissue lymphoma

23

Helicobacter pylori virulence factors

Motility
Adhesin
Urease to raise stomach pH
VacA vacuolating cytotoxin
T4SS cytotoxin releasing system CAG pathogenicity island

24

Salmonella enterica

Gram - rod
Facultative anaerobes
Oxidase neg
Bike salt tolerant and produce hydrogen sulfide
O and H antigens (LPS and flagella)
Lactose and sucrose -

25

Salmonella typhi

Fecal oral
Human reservoir
Chronic carriers with infected gall bladders
Typhoid fever

26

Salmonella virulence factors

LPS
pili
Type III secretion system (invasion through small intestine)
Membrane becomes ruffled and enables transcytosis from apical surface to basolateral membrane

27

Salmonella typhi illness

Gram - shock
3 week incubation period
Fever, lathargy, malaise, constipation
Treatment: supportive care, ciprofloxin, ampicillin

28

Shigella

Gram -
Lactose -
Acid tolerant
Four serogroups based on O antigen
Utilize actin based motility

29

Shigella disease

Fecal oral, direct contact, ingestion of contaminated food and water
Invades epithelium of intestine and causes BLOODY DIARRHEA
shiga toxin--hemolytic uremic syndrome (depurinates the 28S rRNA and inactivated protein synthesis)

30

Shiga toxin

shiga toxin--hemolytic uremic syndrome (depurinates the 28S rRNA and inactivated protein synthesis)
Encoded on a bacteriophage

31

Shigella virulence factors

LPS
shiga toxin
Type III secretion system to allow for internalization
Hemolysins: actin motility

32

E. coli

Gram - rods
Facultative anaerobes
Lactose +

33

E. coli diseases

Gram - shock
Diarrhea
UTIs
Fecal oral transmission
Oxidase -

34

ETEC

Travelers diarrhea: no fever, no inflammation, no blood
LT heat labile toxin and ST heat stable toxin (plasmid encoded)
Colonization factor antigen CFA pili for attachment

35

LT and ST toxin mechanism

E. coli: GM1 receptor and with ADP ribosylate G proteins and lead to elevation of cAMP leading to activation of CFTR nd water follows the electrolytes out of the enterocytes causing hypersecretion and diarrhea

36

EPEC

Enteropathogenic
No CFA, LT, ST
intimin promotes tight adherence
Recruitment of actin and pedestal formation and disrupt the basal membrane and cause diarrhea

37

EIEC

Enteroinvasive
Mild dysentery if shiga toxin is present
Invasin

38

EHEC

Enterohemorrhagic
Adhere to intestine and make shiga toxin
Low grade fever
Secondary infection: hemolytic uremic syndrome

39

Hemolytic uremic syndrome

Anemia, renal failure, thrombocytopenia
Undercooked hamburger
Antibiotics are contraindicated, increase risk of HUS

40

Enterotoxin EC

Enterotoxin delivery

41

Enteropathogenic EC

Intimin with actin bundle and pedestal formation

42

Enteroinvasin EC

Invasin and replication in the enterocyte

43

Enterohemorragic EC

Shiga toxin and dysentery

44

UTIs

E. coli
Cystitis: bladder infection dysuria. No fever or pain
Polynephritis: kidney infection, fever and chills
Progression to gram - shock
Treatment: ciprofloxacin

45

Vibrio cholera

Rice water stools
Gram - rods
Facultative aerobe
Toxin: AB (like LT of E. coli)
Leads to hypovolemic shock

46

Cholera toxin

AB toxin
G protein coupled receptor that activates adenylate cyclase and you get increased cAMP
Massive loss of fluid into lumen
Ribosylation of the G protein

47

Yersinia pestis

Gram - coccobaccili
Oxidase neg
Facultative aerobe (member of Enterobacteriaceae)
Facultative Intracelular pathogen
Transmission: bites by fleas from a rodent
Pneumonic plague is aerosolized

48

Yersinia pestis diseases

Bubonic and pneumonic plague

49

Yersina enterocolitica and yersinia pseudotuberculosis

Diarrheal illness
Fecal oral transmission

50

Yersinia pestis pathogenesis

Bubonic plague
Gram - shock
Flee bite, yersinia drain to lymph node (painful and ulcerated and turn purple) (buboes)
Pneumonic: yersinia in lungs causes whiteout move back to blood and cause gram - shock
Th1 cell mediated immunity required for protection

51

Francisella tularensis

Gram - rod
Rabbits
Tularemia
Complex clinical symptoms : ulcers that can look like bacillus anthracis
LPS
Treat with aminoglycosides

52

Lactose positive opportunistic pathogens

E. coli, Enterobacter, klebsiella

53

Bacteria that cause UTIs

E. coli
Pseudomonas aeruginosa
Proteus vulgaris (urease + can cause kidney stones)
Klebsiella pneumoniae (urease +)

54

Bacterial pneumonia

Strep pneumo
Klebsiella pneumo
Staph aureus
Mycoplasma pneumoniae
Chlamydophila pneumoniae

55

Psuedomonas

Gram - rod
Oxidase +
Lactose -

56

Pseudomonas diseases

Nosocomial: hospital acquired and forms biofilms
Septicemia
Arthritis
Pneumonia (especially in CF patients)
Abscesses
Conjunctivitis
UTI
resistance is common

57

Pseudomonas virulence factors

LPS
Toxins:
exoenzyme S (impairs function of phagocytes) and
exotoxin A (action like diptheria toxin ADP ribosylates EL-2 and inhibits protein synthesis) - necrotizing

58

Burkholderia cepacia

Gram - rod
Co-infects with pseudomonas
High antibiotic resistance
Sensitive to trimethoprim and sulfamethoxazole

59

Anaerobes

Bacteriodes fragilis
Prevotella
Peptostreptococcus
Clostridium
Actinomyces

60

Community acquired aerobic abscesses

Ruptured appendix
Intestinal diverticula
Treat with metronidazole

61

Treponema pallidum disease

Syphilus: rash on palms and soles
More common in men

62

Borrelia

Lyme disease

63

Spirochetes

Treponema: syphilis
Leptospira: leptospirosis
Borrelia: lime disease and relapsing fever

64

Treponema treatment

Penicillin or tetracycline for those with penicillin allergies.
Single high intramuscular dose.

65

Primary syphilis

Transmission via breaks in the skin.
Single lesion (asymptomatic)
Non painful hard chancre
Can look like an Escher chancre of anthrax (gram + spore)
(Haemophilus ducrey is painful)

66

Secondary syphilis

2-10 weeks after primary infection
Systemic infection
Fever, sore throat, headache, lymphadenopathy, distinctive rash on hands and feet
Glomerulonephritis due to immune complex formation
Condylomata lata (warty lesions on genitals)

67

Tertiary syphilis

No treatment of secondary syphilis
Chronic infection and progressive deterioration and death
Gummas (granulomas out lesions) (DTHS)
Neurosyphilis: paralytic dementia, meningitis, seizures, blindness
Cardiovascular symptoms: aneurysms

68

Congenital syphilis

Facial lesions, Hutchinson teeth, thin bones and mental retardation

69

Treponema pallidum diagnosis

Agglutination of beef heart cardiolipin by anti-treponemal antibodies
Rash recognition
Isolation of spirochetes

70

Intramuscular penicillin reaction

Jarisch-Herxheimer Reaction
- mailaise, hypotension, headache, fever
Caused by release of toxic components from dead and dying spirochetes

71

Treponema immunity

Protective immunity: only 25% of primary infections progress to secondary
Immunity depends on T-DTH (Th1 + macrophages

72

Other treponemal diseases

Yaws, pinta, bejel are variants of treponema

73

Leptospirosis

Leptospira interrogans: zoonotic, culturable, aerobic extracellular spirochete
Virulence factors: persistence in host
Hemolysins
Obtained through contact with animal urine: standing water

74

Leptospirosis clinical overview

Presymptomatic, leptospiremia (fever, headache myalgia, gi disturbance, interstitial nephritis), biphasic (initial symptoms subside and second mild illness sets in, kidney and liver failure - altered bile secretion, lightened feces and darkened urine)
Treatment: penicillin, doxycycline
No rash or primary chancre

75

Borrelia ssp.

Microaerophilic spirochetes
Transmitted via insect vector-tick or louse
Lyme disease or relapsing fever

76

Lyme disease

Borrelia burgdorferi
Migrating erythematous rash: doxycycline treatment
Lingering symptoms of fatigue, pain, joint and muscle aches (post-treatment Lyme disease syndrome)
Untreated can lead to progressive arthritis, myocarditis, dementia

77

Borrelia diseases

Lyme disease, anaplasmosis, babesiosis
All transmitted by the same species of tick

78

Relapsing fever

Borrelia recurrentis - louse bourne
Two or more episodes of high fever separated by week long periods of health
IgM against antigens, bacteria have antigen variation, antibodies no longer recognize the bacteria
Treat with tetracycline

79

Borrelia hermsii

Soft ticks - tick borne
Respond well to antibiotics
Relapsing fever

80

Treatment for gonorrhea

Cetriaxone (IM) and azythromycin (orally) for chlamydia trachomatis infections

81

Neisseria

Gram - diplococci
Chocolate agar
Oxidase +
Virulence factors: capsule, pili, antigenic variation, IgA protease
Obligate aerobes
LOS
Ferment maltose

82

Niesseria ssp.

Niesseria meningitidis (polysaccharide capsule) and neisseria gonorrheae (insignificant capsule)

83

Which organisms are known for their capsules?

Neisseria meningitis
Strep pneumo
Haemophilus influenzae

84

MAC attack effective at clearing which infection?

Neisseria meningitidis

85

Neisseria gonorrheae

Coincident with chlamydia trachomatis
Purulent discharge and reproductive consequences (PID)
Silver nitrate drops put in eyes of new borns to protect against ophthalmia neonatorum (from gonorrhea)
Highest rates in black women

86

Diagnosing gonorrheae

Rapid test to detect the presence of bacteria in genital swabs or secretions and is based on Ag-Ab complex formation

87

Neisseria meningitis

Vaccine against capsular polysaccharide - linked to diptheria toxoid
5 serogroups, vaccine against 4 of them
Aerosol
Meningitis and sepsis
Treat with cephalosporin
Meningococcemia that can progress to DIC and shock and destruction of adrenal glands (Waterhouse-Friderichsen Syndrome)

88

Symptoms of meningitis

Abrupt change in behavior, hemorrhagic rash, stiff neck, fever and nausea.
Purulent CSF: neutrophils

89

Treatment of DIC

Vigorous fluid resuscitation, vasopressors to alleviate shock and appropriate antibiotics

90

Chlamydia and mycoplasma

Obligate Intracelular pathogens

91

Chlamydia

Most common sexually transmitted disease
Most often infects women because men don't show symptoms

92

Chlamydia

Obligate intracellular pathogen
Extracellular: inert but infectious elementary bodies
Intracellular: metabolically active reticulate bodies
Chlamydia is readily visualized with giemsa staining
LPS
No cell wall=no penicillin or cephalosporin

93

Chlamydophila psittaci

Severe influenza like disease
Acquired from birds

94

Chlamydophila pneumoniae

Pneumonia syndrome with connections to atherosclerosis

95

Chlamydia trachomatis

Poverty
Mucopurulent infection is chronic and recurrent (ocular infections)
Re infection can cause blindness
Treat with azythromycin
Conjunctivitis
Genital chlamydia

96

Chlamydia trachomatis in men

1-3 week incubation
Dysuria, clear/urethral discharge

97

Chlamydia trachomatis infection in women

Cervicitis, urethritis, salpingitis
PID
Conjunctivitis (trachoma inclusion conjunctivitis in newborns)
Treatment: cetrioxone, azythromycin
Lymphogranuloma venereum (enlargement of the inguinal lymph nodes)

98

Lymphogranuloma venereum differential diagnosis

Yersinia pestis: swelling of the lymph node (gram - rod)
Lymphogranuloma venereum won't gram stain because chlamydia is an intracellular pathogen

99

Latent chlamydia trachomatis infections

Atherosclerosis
Reiter's syndrome: reactive arthritis, host immune response so you treat with anti-inflammatories, not Ab
Urethritis, conjunctivitis, arthritis appear several weeks after primary bacterial infection
Erythemous lesions on glans penis

100

Reiter's syndrome

Reactive arthritis, urethritis, conjunctivitis, arthritis
Caused by
chlamydia,
mycoplasma,
shigella,
salmonella

101

Mycoplasma

No cell wall, only cell membrane
Mycoplasma pneumoniae: walking pneumonia
NO PENICILLIN
Fever, cough, malaise, sore throat, chills, patchy infiltrates on lung X-ray
Treatment: erythromycin or tetracyclines
Anemia and positive detection of cold agglutinins

102

Rickesia rickettsii

Rocky Mountain Spotted fever
Gram - obligate intracellular pathogens
Fever, severe headache, muscle pains, nausea, vomiting, erythematous rash around ankles that spreads to legs
Therapy: doxycycline

103

Rickettsia species

Rickettsia rickettsii (tick vector from animals) and rickettsia prowazekii (lice)

104

Rickettsia pathogenesis

Tick bite, bacteria into capillary, bind endothelial cell, replicate in cytoplasm.
Trigger actin polymerization to spread from cell-to-cell (like listeria and shigella)
Damage to endothelial cells (increased vascular permeability, hypovolemic, edema, ischemia, organ failure)

105

Spotted fever immunity

Ab clearance in extracellular stage and survival of primary infection confers long immunity

106

Rickettsia prowazekii

Typhus
Louse with flying squirrel reservoir
Symptoms: rash, high fever, severe headache, meningoencephalitis, delirium and coma
Fatal due to vascular collapse or pneumonia

107

Ehrlichia and anaplasma

Small gram -
Obligate intracellular pathogens of leukocytes
Bacteria divide and form vacuole bound colonies = morula

108

Human anaplasmosis

Unexplained fever during tick season in Wisconsin
- infects neutrophils
- fever
- no rash
- treat with doxycycline

109

Tick borne diseases

Anaplasmosis (anaplasma phagocytophilum)
Ehrlichiosis (ehrlichia chaffeensis) and (ehrlichia ewingii)
Rickettsia rickettsii
Treat all with doxycycline

110

Coxiella burnetii

Q fever
Aerosol
Relatively resistant to heat and drying
Ticks, rodents, cattle and sheep
Bacteria into macrophage and replicate inside phagolysosome
Symptoms: headache, fever, chills, myalgia, pneumonia and hepatitis

111

Bartonella

Cat scratch disease: lymphadenopathy, bacillary angiomatosis (angiogenesis)
Extracellular pathogen transmitted by various biting insects
Treat with doxycycline