Gram + rods listeria, erysipelothrix Flashcards Preview

BacT RUSVM Summer 15 > Gram + rods listeria, erysipelothrix > Flashcards

Flashcards in Gram + rods listeria, erysipelothrix Deck (54)
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1
Q

Whats a good way to get yourself infected with listeria?

A

unpasteurized foods and lunch meat.

Crosses placenta!

2
Q

What are some details about listeria?

A

Small, Gram + facultative anaerobic rods

3
Q

What temperature range does listeria grow in?

A

4-44oC

4
Q

Where in animals is listeria usually found?

A

GI Tract

5
Q

How thriving is Listeria?

A

it is resistant to harsh environmental conditions, Ubiquitous in the environment, especially temperate zones.

6
Q

how common is listeria?

A

it is a sporadic disease in a variety of animals including man

7
Q

What does monocytogenes mean?

A

Can survive in macrophages

8
Q

What is the most frequent Listeria species?

A

Listeria monocytogenes- associated with all forms of disease in multiple hosts including humans

9
Q

occasionally this species of listeria is seen associated with ruminant abortion?

A

Listeria ivanovii

10
Q

Listeria species rarely seen that is reported from CNS in ruminants?

A

listeria innocua

11
Q

what time of year does this disease mainly affect?

A

Winter spring of feedlots or housed ruminants

12
Q

Outbreaks of listeria usually happen when?

A

after feeding poor-quality silage.

13
Q

Why is this disease important?

A

MONEY always money with seasonal occurance (winter months)

14
Q

how is Listeria taken up by a host?

A

Ingestion or inhalation> septicemia, abortion, and latent infection.

15
Q

where does listeria affect animals when absorbed through buccal cavity?

A

Trigeminal nerver and then brain stem

16
Q

What is a poultry infection of listeria called?

A

septicemic listeriosis

17
Q

What is the pathogenesis of Listeria?

A

Invasive ( direct invasion of epithelial cells) enters blood steram
Facultative intracellular bacteria: persit in macrophages
Intracellular growth leads to cell death and focal microabscesses.

18
Q

How does the disease present?

A

Encephalitis- most common presentation in ruminants. bacteria invade oral mucosa and travel along trigeminal nerve to brainstem.

Abortion- hematogenous spread to gravid uterus, organisms penetrate the placenta and spread to fetal liver resulting in focal hepatic necrosis.

Speticemia; common in monogastrics, intracellular replication in macrophages, multifocal miliary abscess in spleen. liver. mainly occurs in neonates as a continuation of the fetal infection

19
Q

What are the virulence factors of listeria?

A
Internalin ( gain entry to macrophages).
listeriolysin O (hemolysin): required for intracellular multiplication facilitate bacterial release from phagosomes
Act A: Intracellular movement (one cell to another)
20
Q

L. monocytogenes uses what to travel between cells and evade antibodes?

A

Host actin filaments

21
Q

What diseases are associated with Listeria?

A

Neurologic symptoms: dullness, turning or twisting of head to one side, walking in circles (circling disease)

Unilateral facial nerve paralysis with drooping of eylid and ear, drooling to pharyngeal paralyis, strabismus, nystagmus, hemiparesis, head pressing, decreased rumen motility.

Purulent endophthalmitis, usually unilateral

22
Q

What lesions are associated with listeria?

A

Microabscesses and glial nodules infiltrated by neutrophils and gitter cells that may contain bacteria.

Acute vascular fibrinoid necrosis secondary to drainage into virchow-robin space

Leptomeningitis and densly cellular perivascular cuffs composed of lymphocytes and histiocytes with fewer neutrophils and eosinophils

neuronal necrosis

Crainial nerves may have intrafasicular and perineural accumulations of inflammatory cells (Lymphocytes, macrophages, plasma cells, and neutrophils)

23
Q

what are the DDx of listeria?

A
pregnancy toxemia in ewes
ketosis in cattle
BSE
thrombotic meningoencephalitis
polioencephalomalacia-(thymine difficiency)
sporadic bovine encephalomyelitis lead poisoning
Rabies
Parasitic infections
Vestibular disease
24
Q

How does the clinician diagnose listeria ante-mortem?

A
CNS disease
Presumptive Dx from symptoms
Listeria enrichment culture
Gram stained CSF sediment short intracellular and extracellular Gram + bacteria
Septicemia culture of liver and spleen
25
Q

how does the clinician diagnose listeria Post mortem?

A

No Gross lesions, Histopathology, culture of brainstem

immunohistochemical staining

26
Q

how do you treat listeria?

A

Penicillin (drug of choice)
ceftiofur, erythromycin, TMPS
High doses required because of difficulty achieving minimum bactericidal concentrations in the brain

27
Q

Listeria and zoonosis and theres a lot

A

mild flu like symptoms, febrile gastroenteritis to meningitis and or meningoencephalitis

occurs in pregnant women, neonates, the elderly and immunocompromised individuals. healthy individuals may also be affected

meningitis, frequently accompanied by septicemia

fetal infection and abortion, stillbirth, or delivery of an acutely ill infant.

28
Q

Listeria disease outcome depends on?

A

number of organisms exposed to
route of exposure
virulence of strain
immune status of host

29
Q

Are there vaccines for listeria?

A

Nope, cell-mediated immunity important

30
Q

How does one protect themselves from listeria disease?

A

avoid high risk foods

  • poor quality silage, ph>5.5
  • unpasteurized dairy products
  • processed meats
  • undercooked vegetables

Minimize aerosol exposure in areas where microbe is present

precautions for pregnant and immunocompromised animals

31
Q

What are the details of Erysipelothrix?

A

Small, non-sporeforming gram+ rods

32
Q

What is the common species of Erysipelothrix?

A

E. rheusiopathiae- most common in pigs and birds but also seen in many other species including humans (serotypes 1a, 1b and 2 common in pigs)

33
Q

what erysipelothrix species is avirulent in pigs but virulent in dogs?

A

E. tonsillarum

34
Q

Swine bacterial infection and navle!!!

A

Erysipelothrix
facultative anaerobe bacillus
swine are most important reservoir

35
Q

what percentage of swine harbor erysipelothrix?

A

30-50% in tonsils or other lymphoid tissue.

36
Q

What age of swine are most susceptible to erysipelothrix?

A

3 months to 1 year of age and pregnant sows.

37
Q

disease manifestations of erysipelotrhix include?

A

septicemia, polyarthritis, and endocarditis

38
Q

What is the transmission and virulence factors of erysipelothrix?

A

primarily oral, infection of palatine tonsil or GALT
Can enter through skin abrasion

Neuraminidase= adherence to endothelial cells
Heat labile capsule= resists phagocytosis by neutrophils

39
Q

what is the sign of all signs on pigs with erysipelothrix infection?

A

rhomboid shaped patches on the skin

40
Q

What acute diseases does erysipelothrix cause?

A

septicemia, common (pigs, birds other)
Abortion, rare (pigs)
cutaneous cellulitis/ utricaria, occasional (pigs birds man)

41
Q

what subacute diseases does erysipelothrix cause?

A

vegetative (valvular) endocarditis, occasional ( pigs, birds, humans, others) Idk what others is?

42
Q

What chronic disease does erysipelothrix cause?

A

arthritis, common (pigs, birds)

43
Q

what is the DDx for erysipelothrix?

A

salmonella choleraesuis
classical swine fever virus (porcine pestivirus)
Dermatitis and nephropathy syndrome of pigs (cutaneous and systemic necrotizing vasculitits)

44
Q

Erysipelothrix in lambs/ sheep?

A

fivrinopurulent polyarthritis and osteomyelitis; cutaneous lesions occasionally, usually happens without history of contact wit swine

45
Q

erysipelothrix in turkeys

A

with acute disease- septicemia, cyanotic combs, hemorrhage (breast and leg muscles), splenomegaly; with chronic disease- polyarthritis and endocarditis. Adult toms most commonly affected

46
Q

Marine mammals and erysipelothrix

A

acute septicemia or similar skin lesion to SE

47
Q

Calves and erysipelothrix

A

poly arthritis

48
Q

humans and erysipelothrix

A

erysipeloid. usually a localized skin lesion but may rarely be systemic

49
Q

what causes human erysipelas?

A

Group A beta-hemolytic streptococci

50
Q

which type of morphology is usually the virulent type?

A

Short rod form

smooth colony type

51
Q

How is erysipelothrix diagnosed?

A

culture

52
Q

what is the treatment of erysipelothrix?

A

Penicillin tetracycline

53
Q

how do you control erysipelothrix?

A

treat and isolate infected animals
cull chronically affected animals
good hygiene practices

54
Q

Vaccination of erysipelothrix?

A

Pigs and turkeys
(live attenuated + Bacterin (killed preparation of bacteria used for vaccination))
surface proteins