5.10 Curved Gram Negative Rods and Spirochetes

Question 1

what is the characteristic appearance of campylobacter spp. on staining

Answer 1

seagulls (gram-negative curved rods)

Question 2

what is the habitat(s) of campylobacter

Answer 2

intestinal; genital tract in some species

Question 3

what are the two main Campylobacter spp of interest, what is their host(s) and what do they cause

Answer 3

• C. jejuni (all species) -> diarrhea
• C. coli (pigs, humans) -> diarrhea

Question 4

T/F campylobacter jejuni is zoonotic and reportable

Answer 4

F; zoonotic but not reportable

Question 5

what is the major difference between campylobacter and salmonella

Answer 5

campylobacter cannot replicate in food whereas salmonella can; lower infectious dose for campylobacter

Question 6

what are the conditions in which C. jejuni infection is more common

Answer 6

poor hygiene and close contact between farm animals; more common in young vs adult animals

Question 7

what is the route of infection of campylobacter jejuni

Answer 7

fecal contamination of food or water

Question 8

what is the main reservoir for C. jejuni? C. coli?

Answer 8

C. jejuni: broiler chickens
C. coli: pigs

Question 9

what type of diarrhea does C. jejuni cause (2 names for the diseases)

Answer 9

superficial erosive colitis and ileitis-colitis

Question 10

what are the two “outcomes” of C. jejuni infection

Answer 10

• self-limiting infection that resolves within 1-2 weeks
• bacteremia and abortions if it becomes severe

Question 11

what are the two C. jejuni toxins

Answer 11

1) Cytolethal distending toxin (cdt gene)
2) LT-like adenylate cyclase-activating enterotoxin

Question 12

the ____________ toxin is responsible for erosions and _________ toxins is responsible for diarrhea caused by C. jejuni

Answer 12

cytolethal distending toxin; LT-like adenylate cyclase activating enterotoxin

Question 13

what special media and conditions are used to culture C. jejuni

Answer 13

selective (feces); microaerophilic (6% O2)

Question 14

how do we treat C. jejuni

Answer 14

antibiotics

Question 15

certain serotypes of C. jejuni are responsible for what disease in humans? What is it characterized by

Answer 15

Guillain-Barre syndrome; PNS demyelination

Question 16

what is the main source of C. jejuni infection in humans (be specific)

Answer 16

contaminated raw chicken

Question 17

what are some ways to control C. jejuni

Answer 17

food production and kitchen hygeine; preventing cross-contamination; cooking meat fully; slaughterhouse processing

Question 18

T/F there is a C. jejuni vaccine available for chicken

Answer 18

F

Question 19

where does Lawsonia intracellularis live

Answer 19

in the apical cytoplasm of ileal epithelial cells

Question 20

what does Lawsonia intracellularis cause in young animals? old animals?

Answer 20

young: proliferative intestinal adenomatosis (diarrhea, decreased weight gain)

old: proliferative hemorrhagic enteropathy (PHE)

Question 21

Lawsonia intracellularis mainly infects what animals

Answer 21

weaner pigs and yearling foals

Question 22

T/F Lawsonia intracellularis has a broad host range

Answer 22

T

Question 23

T/F Lawsonia intracellularis is zoonotic and reportable

Answer 23

F; zoonotic but not reportable

Question 24

how is Lawsonia intracellularis diagnosed

Answer 24

PCR on feces, ELISA

Question 25

how do we control Lawsonia intracellularis

Answer 25

vaccination, antimicrobials, raising specific pathogen-free pigs

Question 26

what is the structure of Spirochaetales spp.

Answer 26

coiled spiral organisms wrapped around an internalized flagellum

Question 27

how do we stain Spirochaetales

Answer 27

using silver stain or dark field; do not stain well with gram

Question 28

what are the Genera of Spirochaetales of interest to us

Answer 28

Leptospira and Borrelia

Question 29

what lab test results are characteristic of leptospirosis and what diseases does this indicate

Answer 29

elevated creatinine and blood urea; elevate creatine phosphokinase and other muscle enzymes; elevated bilirubin and alkaline phosphatase indicates renal failure and hepatitis

Question 30

T/F leptospirosis is zoonotic and reportable

Answer 30

F; zoonotic but not reportable

Question 31

T/F it takes a long time to grow leptospira and requires special medium and conditions

Answer 31

T

Question 32

T/F all Leptospira spp. are pathogenic

Answer 32

F

Question 33

what is the difference between the old and new antigenic classification for Leptospira

Answer 33

Old: 23 serogroups and 250 serovars New: >60 species, then serovars

Question 34

what conditions do Leptospira require for survival

Answer 34

wet, warm environments

Question 35

T/F Leptospira are fastidious

Answer 35

T

Question 36

what is the specific location in the body for leptospira

Answer 36

proximal convoluted tubule of kidney

Question 37

what is the difference in infection between maintenance and accidental (incidental, non-maintenance) hosts of leptospira

Answer 37

maintenance: lifetime infection in kidney +/- genital tract accidental: kidney infection for a few weeks

Question 38

what is the classic "iceberg" infection

Answer 38

Leptospira (most infections subclinical or chronic)

Question 39

do we see clinical signs of Leptospira in maintenance hosts, accidental hosts or both

Answer 39

in accidental (subclinical/chronic infections in maintenance)

Question 40

T/F leptospira can cause bacteremic disease; if T, where does it localize

Answer 40

T: liver, kidney, CSF, eye

Question 41

what are the maintenance vs incidental hosts of leptospira

Answer 41

maintenance: rodents accidental: racoons, beavers, dogs, humans

Question 42

describe the following manifestations of leptospira: - peracute - acute - chronic - subclinical

Answer 42

peracute: DIC, hemorrhage, death acute: nephritis, hepatitis, abortion, fever chronic: chronic nephritis, abortion (pigs, dogs) subclinical: antibody rise only or mild flu-like illness

Question 43

what type of leptospira is common in dogs and what are the clinical signs

Answer 43

Leptospira canicola: acute or chronic renal failure (interstitial nephritis)

Question 44

What spp of Leptospira is common across large animal species and what are the signs/clinical dz

Answer 44

Leptospira pomona: abortion in all; nephritis in pigs; haemoglobinuria and mastitis in cows; uveitis in horses

Question 45

How can we detect L. hardjo, in what species and why

Answer 45

in milk; causes mastitis (as well as abortion, stillbirth) in cows

Question 46

what Leptospira is a major cause of acute renal failure in dogs? what else does it cause

Answer 46

L. grippotyphosa; hepatitis and fever

Question 47

how do we detect Leptospira (be specific)

Answer 47

paired serum samples: want to see a 4x increase between the first and second ELISA; can also do direct demonstration (PCR; immunofluorescence; dark field)

Question 48

why are the Leptospira vaccines not fool-proof

Answer 48

they do not protect across all serovars (5 or 6 covered)

Question 49

how can we control/treat Leptospira

Answer 49

vaccination; vector control (rodents); antibiotics

Question 50

where is Borrelia burgdorferi a problem

Answer 50

eastern, central, western US (due to resurgence in deer population)

Question 51

describe the 3-host lifestyle of Borrelia burgdorferi

Answer 51

eggs hatch into Borrelia-free larvae -> feed on rodents/birds +/- pick up Borrelia -> become nymph -> feed on rodents/birds +/- pick up Borrelia -> become adult -> feed on deer or accidental host (dogs, humans)

Question 52

what is the characteristic lesion created by Ixodes scapularis bite (tick carrying Borrelia burgdorferi)

Answer 52

target

Question 53

which of the following stages of Borrelia burgdorferi are potentially infective: - egg - larvae - nymph - adult

Answer 53

- nymph - adult

Question 54

if you remove an adult tick within ____ you likely prevent transmission of Borrelia burgdorferi

Answer 54

24h

Question 55

T/F Borrelia burgdorferi is reportable and zoonotic

Answer 55

F; zoonotic but not reportable

Question 56

what are the two main Ixodes spp. that carry Borrelia burgdorferi and where are they located

Answer 56

western US/BC: Ixodes pacificus eastern/central USA: Ixodes scapularis

Question 57

where is lyme disease currently spreading

Answer 57

along the north shore of Lakes Erie and Ontario; Thousand Islands area

Question 58

what are the acute and chronic signs of Borrelia burgdorferi infection in PEOPLE

Answer 58

acute: erythematous skin rash; fever; joint pain; muscle pain; meningeal irritation chronic: peripheral neuropathy; arthritis; myocarditis

Question 59

what does Borrelia burgdorferi cause in dogs (4)

Answer 59

fever, anorexia, arthritis, protein-losing glomerulopathy

Question 60

what does Borrelia burgdorferi cause in horses

Answer 60

arthritis, abortion, panuveitis, encephalitis

Question 61

how do we diagnose Lyme disease and why is it difficult in endemic areas

Answer 61

serology and response to antibiotics; hard to diagnose in endemic areas because many animals have seroconverted due to subclinical infection/exposure

Question 62

how can we control Borrelia burgdorferi infection

Answer 62

vaccination