Lecture 29 - Lawsonia

Question 1

What species are present in the genus Lawsonia?

Answer 1

Intracellularis

Question 2

What are that basic characteristics of L. Intracellularis?

Answer 2

Non-spore forming
Microaerophilic
Curved-shaped bacillus
Obligate intracellular

Question 3

What is the structure of the membrane of L. Intracellularis?

Answer 3

Trilaminar

Question 4

What other bacteria has a trilaminar membrane?

Answer 4

Mycoplasma

Question 5

What is needed to grow L. Intracellularis?

Answer 5

Cell-free media doesnt work

Dividing cell culture needed with microaerophilic atomosphere

Question 6

What is the method by which L. Intracellularis gets into its host?

Answer 6

Adheres to enterocytes then invades them

Leaves the phagosome and hangs out in the cytoplasm of the enterocyte

Question 7

What does L. Intracellularis do to enterocytes?

Answer 7

Induces hyperplasia

Question 8

What immune response occurs with L. Intracellularis infections?

Answer 8

None really

See no real inflammation at site of infection and T/B cell response is reduced

Question 9

how is L. Intracellularis transmitted?

Answer 9

Fecal-Oral

Question 10

What are the three major results see in the host due to the hyperproliferation caused by L. Intracellularis?

Answer 10

Thickening of the mucosa = hypertrophy
Increased non-functioning crypt cells = malabsorption
Fecal shedding

Question 11

What animals is proliferative enteropathy an emerging disease?

Answer 11

Horses

Question 12

Where was proliferative enteropathy first seen?

Answer 12

Pigs

Question 13

What is the model for horse?

Answer 13

Rabbit

Question 14

What is the model for pigs?

Answer 14

Hamster

Question 15

What lesions are seen with L. Intracellularis infections?

Answer 15

Intestinal hyperplastic lesions

Question 16

What is thought to be the carrier host of L. Intracellularis?

Answer 16

Dogs

Question 17

Why are dogs though to be the carrier host of L. Intracellularis?

Answer 17

Have serum antibodies present for L. Intracellularis even without disease

Question 18

What form of L. Intracellularis infection is most common in pigs?

Answer 18

Chronic

Question 19

What are the reserviors for L. Intracellularis in pig populations?

Answer 19

Rats + Mice

Question 20

When do you see clinical L. Intracellularis disease in pigs?

Answer 20

With stress

Question 21

What are the two presentations of the chronic form of L. Intracellularis seen in pigs

Answer 21

PIA
– and –
PHE

Question 22

Term: PIA

Answer 22

Porcine Instestinal adenomatosis

Question 23

What age does PIA occur?

Answer 23

6 to 20 weeks

Question 24

What symptoms are seen with PIA?

Answer 24

Water to pasty, brownish blood stained poop
Poor growth
Can recover spontaneously

Question 25

What is seen with severe PIA?

Answer 25

Coagulative necrosis of adenomatous mucosa | Can recover spontaneously

Question 26

Term: PHE

Answer 26

Proliferative hemorrhagic enteropathy

Question 27

When is PHE seen?

Answer 27

4 to 12 months

Question 28

What symptoms are seen with PHE?

Answer 28

Cutaneous pallor + Weakness Black tarry feces Die quick

Question 29

What are the differential diagnosis for PHE?

Answer 29

Swine dysentery Gastric ulcers Salmonella

Question 30

What are the resiviors in horse populations?

Answer 30

Rabbits

Question 31

What is the window of risk seen in weanling horses?

Answer 31

Decreased colostrum Ab's -- and -- Mounting own cell-mediated response plus have a lot of stress

Question 32

What symptoms area seen in horses with L. Intracellularis infections?

Answer 32

Lethargy + Anorexia + Fever Hypoproteinemia + Hypoalbunemia Peripheral edema!!

Question 33

What are the differiential diagnosis for horses with L. Intracellularis infections?

Answer 33

Parasitism Bacterial infection Viral infection Plant toxicity

Question 34

What bacterial infections can look like L. Intracellularis?

Answer 34

Clostridium Salmonella Rhodococcus

Question 35

What is the preferred method of confirmation of a L. Intracellularis infection in both horses and pigs?

Answer 35

IPMA - immunoperoxidase monolayer assay

Question 36

What is done diagnostically in horses only when a L. Intracellularis infection is suspected?

Answer 36

Blood work + Ultrasound

Question 37

What special stain is used for L. Intracellularis?

Answer 37

Warthin-Starry sliver stain

Question 38

What is the treatment for L. Intracellularis?

Answer 38

Oxytetracycline + Doxycyline

Question 39

What characteristics of an AB must be present to treat L. Intracellularis?

Answer 39

Lipophilic or aamphoteric to concerntrate in host cytoplasm

Question 40

What vaccine is avalible for L. Intracellularis? Why is this different?

Answer 40

Pigs - take orally in drinking water Horses - rectally ITS THE SAME VACCINE