Gram-Negative Bacilli

Front 1

What differentiates Gram+ from Gram-?

Back 1

Unlike the Gram positive cell wall, the Gram negative cell wall contains a thin peptidoglycan layer adjacent to the cytoplasmic membrane, which is responsible for the cell wall's inability to retain the crystal violet stain upon decolourisation with ethanol during Gram staining.

In addition to the peptidoglycan layer, the Gram negative cell wall also contains an additional outer membrane composed by phospholipids and lipopolysaccharides which face into the external environment.

Front 2

What are the antigenic structures of Gram-negative bacteria?

Back 2

O-polysaccharide (side chains of LPS)

H antigen -- on flagella (antibody can immobilize)

K antigen -- capsular material

Front 3

3 examples of exotoxin in Gram-negative bacteria:

Back 3

Cytotoxin
Hemolysin
Enterotoxin

Front 4

LPS is an example of what type of Gram-negative virulence factor?

Back 4

LPS is an endotoxin

Front 5

Which is more reliable, a Gram-stain or a culture?

Back 5

Gram-stai is more reliable than a culture

Front 6

Illness associated with:
E. coli

Back 6

UTI
bacteremia
intraabdominal infection
neonatal meningitis

Front 7

Illness associated with:
Shigella

Back 7

enteric infection

Front 8

Illness associated with:
Salmonellae

Back 8

enteric infection

Front 9

Illness associated with:
Yersiniae

Back 9

plague
enteric infection

Front 10

Illness associated with:
Klebsiellae

Back 10

UTI
pneumonia
bacteremia
nosocomial infection
postoperative meningitis

Front 11

Illness associated with:
Proteus

Back 11

UTI
soft-tissue infection
bacteremia

Front 12

Medically important Enterobacteriaceae include:

Back 12

Shigella
Salmonella
Yersinia
Klebsiella
Proteus

Front 13

Common clinical syndromes associated with Enterobacteriaceae include:

Back 13

bacteremia
UTI
gastroenteritis
pneumonia
soft-tissue infections
meningitis
osteomyelitis
...nearly everything!

Front 14

E. coli causes everything except:

Back 14

pneumonia

Front 15

Klebsiella does not cause, what?

Back 15

enteric infections

Front 16

Clinical syndromes associated with Yersinia pestis

Back 16

Bubonic - acute lymphadenitis
Septicemic - fever, hypotension, no bubos
Pneumonic - cough, hemoptysis, no bubos
Cutaneous - pustule, eschar, with bubo
Meningitis - fever, nuchal rigidity, with bubo

Front 17

Clinical syndromes associated with Yersinia enterocolitica

Back 17

enterocolitis (2/3)
LN in mesentary are inflammed
bacteremia
hepatic abscess
osteomyelitis
endocarditis

**able to grow in low temps

Front 18

Clinical syndromes associated with Yersinia pseudotuberculosis

Back 18

pseudoappendicitis
lethal bacteremia despite antibiotics

Front 19

Vibrios (alginolyticus and vulnificus) are often associated with what clinical condition?

Back 19

cellulitis

**Chesapeake Bay, digging for clams

Front 20

Aeromonas (hydrophilia and sobria) are often associated with what clinical condition?

Back 20

soft tissue infections

**Chesapeake Bay

Front 21

Pasturella multocida is associated with what clinical condition?

What is significant about the onset?

Back 21

Focal soft tissue infections (onset of inflammation is FAST!)
Acute respiratory infections
Bacteremia

Front 22

Brucellosis is commonly associated with slaughterhouse workers and veterinarians.

What are the clinical manifestations?

Back 22

Multiply in LN -> dissemination -> Localize in liver, spleen, kidney (RES) -> GRANULOMAS -> casseous necrosis

They are intracellular parasites that multiply in macrophages. Cell-mediated immunity required!

**non-specific symptoms (undulant fever, sweats, malaise, abdominal pain, loss of appetite)

Front 23

What are the clinical forms of Tularemia?

Back 23

Ulceroglandular 21-87%
Glandular 3-20%
Typhoidal 5-30%
Pneumonic 7-20%

Front 24

What clinical manifestations are associated with Tularemia?

Back 24

Pulse-temperature dissociation in 42%
cough, myalgias, chest discomfort, sore throat, vomiting, diarrhea...

Front 25

Bartonella bacilliformis causes Oroya Fever, which manifests how?

Back 25

Chronic verruga (cutaneous nodules) that may persist for years.

Carrion's Disease
Bacterial penetrate erythrocytes, causing RBS fragility and anemia.

Front 26

Bartonella hensalae causes what disease?

Back 26

Cat Scratch Disease

Granulomas with central necrosis and giant cells. Disseminated tissue infection may be associated with bacteremia. Seen in AIDs patients.

Front 27

Acinetobacter species are associated with what serious medical problem?

Back 27

Multi-drug resistance