Gram + Cocci&Rods Flashcards
1
Q
What are the species of Actinomyces?
A
A. viscosus, A. naeslundii, A. israelii, A. hordeovulneris
2
Q
What is the most common staphylococcus isolate from dogs?
A
Staphylococcus pseudintermedius
3
Q
Blackie, a 5-year old female dog was presented to the vet clinic with unresolving skin lesions. Purulent and bloody secretions were oozing out of some of the lesions. Which of the following staphylococcus species is mostly involved in this type of cases in dogs?
- Staphylococcus aureus
- Staphylococcus pseudintermedius
- Staphylococcus hyicus
- Staphylococcus epidermis
A
(test question)
- Staphylococcus pseudintermedius
4
Q
Staphylococcal enterotoxin exerts its pathogenic effect by
- Binding indiscriminately to the T cell receptor and Class II MHC molecule
- Binding to receptor using the B unit activation of an enzyme using the A unit
- Binding to the CD 14 receptor and activating macrophages to release TNF alpha
A
- Binding indiscriminately to the T cell receptor and Class II MHC molecule (superantigen)
5
Q
What are the correct characteristics of Actinomyces? A. Facultative anaerobes B. Facultative anaerobes, Facultative aerobes C. Facultative anaerobes, Facultative aerobes, Capnophillic D. None of the above
A
C. Facultative anaerobes, Facultative aerobes, Capnophillic
6
Q
T/F Actinomyces are catalase positive.
A
False. catalase NEGATIVE
7
Q
How would you describe the colonies of Actinomyces?
A
small, slow growing, “molar tooth like”
8
Q
Actinomyces reside in soil. What are these organisms called?
A
Soil dwelling saprophytes
9
Q
Where do you find Actinomyces in the host? What kind of infection is this?
A
Oropharynx (SOME HOST RESTRICTED); Polymicrobial infection.
10
Q
Describe the GENERAL morphological characteristics of the disease that Actinomyces cause.
A
Localized, chronic, progressive, pyogranulomatous disease (mandible, maxillae, etc)
11
Q
What kind of disease does Actinomyces bovis cause? Explain the characteristics of this disease.
A
LUMPY JAW (pyogranulomatous osteomyelitis); facial distortion, lose teeth, dyspnea
12
Q
Describe morphology of Actinomyces.
A
Gram+, club-shaped rods and filaments, presence of SULFUR GRANULES
13
Q
What is the diagnosis for Actinomyces?
A
Culture (aerobic and anaerobic culture); microscopc of granules
14
Q
What are the treatments for Actinomyces?
A
PENICILLIN G (high dose), iodides; long term treatment (3-12 months), surgical excision, culling.
15
Q
T/F. Actinomyces cause an infectious disease.
A
False. SPORADIC DISEASE.
16
Q
What are the diseases caused by A. hordeovulneris?
A
Canine sublumbar abscess and canine epicarditis (DUE TO FOXTAIL)
17
Q
What are some ways to control Actinomyces related diseases?
A
Minimize risk of mechanical injury and remove foreign bodies.
18
Q
A bacteria which uses host actin filaments to travel between cells
- Listeria monocytogenes
- Erysipelothrix rhusiopathiae
- Bacillus anthracis
- Streptococcus iniae
A
1. Listeria monocytogenes
19
Q
Which of the following is incorrect about listeriosis in ruminants?
- Outbreaks occur after feeding soiled silage
- Encephalitis and neurological signs occurs after the organism enter through the wounds in the buccal mucosa
- Generally disease occurs in the winter months
- Hepatic necrosis is the main lesions in adult animals
A
- Hepatic necrosis is the main lesions in adult animals
* (only in young animals and monogastrics)*
20
Q
T/F. Infections of Trueperella pyogenes are endogenous.
A
True.
21
Q
How do Actinomyces species spread?
A
DIRECT EXTENSION (Lymphogenous and hematogenous spread).
22
Q
What type of pathogen is Rhodococcus equi?
- Obligate mammalian
- Facultative intracellular
- Obligate intracellular
- Facultative mammalian
A
- Facultative intracellular
23
Q
T/F. Trueperella pyogenes are pleomorphic, facultative aerobes, non-spore, non-motile, non-capsulated, capnophilic.
A
False. FACULTATIVE ANAEROBES (everything else is true).
24
Q
Where do Trueperella pyogenes reside? A. Mucous membrane B. Oral cavity C. Bones D. GI tract
A
A. Mucous membrane
25
What induces Trueperella pyogenes infection? What type of infection do they cause?
Precipitating stress or trauma; Suppurative.
26
T/F. Infections of Trueperella pyogenes are endogenous.
True.
27
What is a disease that is caused by Trueperella pyogenes? "Communicable disease among pastured dairy cattle during dry period"
SUMMER MASTITIS
28
Which species of animals are proned to Trueperella pyogenes infections?
Swine and cattle (cattle more susceptible; causes ABORTION and MASTITIS in cattle).
29
What is the most important virulence factor of Actinobaculum suis?
Urease
30
What is the treatment/control for Trueperella pyogenes infection?
Difficult to treat (none).
31
T/F. Actinobaculum suis requires oxygen in order to survive.
False. They are ANAEROBES.
32
Which species of gram + rods has "commensal diphteroid" characteristic? A. Actinomyces B. Actinobaculum suis C. Streptococcus D. Dermatophils congolensis
B. Actinobaculum suis
33
Where does Actinobaculum suis usually reside in the body of a boar?
Prepucial mucosa
34
How is Actinobaculum suis transmitted to another animal?
SEXUALLLLL!!
35
What is the most important virulence factor of Actinobaculum suis?
Urease
36
What does Actinobaculum suis cause?
Cystitis and pyelonephritis (3-4 weeks post-coitus)
37
What is the pathogenesis of pyelonephritis caused by Actinobaculum suis similar to?
BOVINE PYELONEPHRITIS (C. renale)
38
What are two important diagnosis for Dermatophils congolensis?
Culture (selective and non-selective growth on blood agar) Microscope of scabs: "tram track" (methylene blue stain of Giemsa stain)
39
What is NOT a characteristic of Dermatophils congolensis? A. Filamentous, branching, 2 planes. B. Motile zoospores (chemotaxis for CO2) C. Aerobic, catalse positive D. Non-spore, non-capsulated, capnophilic
D. Non-spore, non-capsulated, capnophilic
40
Where can you find Dermatophils congolensis on an animal?
Skin (MOIST and DAMAGED)
41
T/F. Streptococcus is the most common causing bacterial skin infection in dogs.
FALSE! STAPHYLOOOOOOOOCOCCUS
42
Name the species of animals that are affected by Dermatophils congolensis.
Cattle, sheep, goats, horses (not as much for pigs, dog, and cats).
43
Name THREE diseases that are caused by Dermatophils congolensis.
Epidermal abscesses with hyperkeratosis Rain scald: horse (when it's raining) ![]() Strawberry Footrot: cattle ![]()
44
What are two important diagnosis for Dermatophils congolensis?
Culture (selective and non-selective growth on blood agar) Microscope of scabs: "tram track" (methylene blue stain of Giema stain)
45
What is the BEST treatment for Dermatophils congolensis?
Antibiotic (penicillin G and tetracycline)
46
What is true about Staphylococcus species? A. They cause strangles in equine. B. The most important virulence factor is capsule (hyaluronic acid) C. The best diagnosis is to use PCR for skin infection. D. they are opportunistic pathogens/resident flora.
D. they are opportunistic pathogens/resident flora.
47
T/F. Streptococcus is the most common causing bacterial skin infection in dogs.
FALSE! STAPHYLOOOOOOOOCOCCUS
48
What disease does S. hyicus cause?
Greasy pig disease/exudative epidermitis
49
T/F. Staphylococcus species have ONLY positive catalases.
False. positive AND negative catalases (positive is MORE PATHOGENIC)
50
T/F. All Staphylococcus species are facultative anaerobes.
False. S. sacharolyricus and S. aureus subsp. anaerobius are are not.
51
Where is the natural habitat for Staphylococcus?
Skin and mucous membranes.
52
What is true about Staphylococcus species? A. They cause strangles in equine. B. The most important virulence factor is capsule (hyaluronic acid) C. The best diagnosis is to use PCR. D. they are opportunistic pathogens/resident flora.
D. they are opportunistic pathogens/resident flora.
53
What are the diseases that are caused by S. aureus? (include which animals are affected if there is any)
Mastitis (cattle), Ulcerative Pododermatitis, Bumble foot in birds (birds), Chronic pyogranulomatous inflammation (rodents, humans, horses)
54
What disease does S. hyicus cause?
Greasy pig disease/exudative epidermitis
55
Which species of staphylococcus causes "necrotizing fasciitis and necrotizing pneumonia"?
S. pseudintermedius
56
How would you diagnose Staphylococcus?
Direct exam (abundance of neutrophils), staining, culture (semiquantitative), PCR (except skin infection)
57
What is the first choice drug to treat staphylococcus infections?
Cephalosporin
58
T/F. Local therapy and intra-articular injection are effective towards Staphylococcus infections. Also, topical can be used for superficial infection.
True.
59
Which species of Staphylococcus is the common isolate in dogs? A. S. Intermedius B. S delphini C. S. pseudintermedius
C. S. Pseudintermedius
60
T/F. Staphylococcus species are Beta-lactamase, methicillin, and multi-drug resistant.
True.
61
What is the GENERAL term for Staphylococcus infection?
SUPPURATIVE (skin infections, wound infections)
62
What is used to see the source of bacteria (either the pet or the owner)?
Pulse Field Gel Electrophoresis
63
What is the best treatment for mature staphylococcal abscess?
OPEN, CLEAN, and FLUSH IT WITH NO ANTIMICROBIALS
64
Name infection controls for straphylococcal diseases.
Contact precautions, hygiene, awareness of increased risk, isolation, immunocompetent older clients, treatment of colonized pet is NOT normal
65
Which species of Staphylococcus is the common isolate in dogs? A. S. Intermedius B. S delphini C. S. pseudintermedius
C. S. Pseudintermedius
66
T/F. All streptococcus species are facultative anaerobes.
True.
67
T/F. All streptococcus species have POSITIVE catalases.
False. NEGATIVE catalases
68
Name FIVE natural habitats for Streptococcus.
Oral cavity, GI tract, nasopharynx, skin, genital tracts
69
How are streptococcus species transmitted?
Direct contact, fomites.
70
T/F. Staphylococcus is a reportable disease in some states.
FALSE. STREPTO IS!!!!!!!!!!
71
What are three diagnosis of S. equi?
Culture swab, serology, PCR.
72
T/F. Staphylo recover spontaneously.
FALSE. STREPTO!! (recover after abscess ruptures; strong immunity after recovery)
73
Which species of strepto causes strangles?
S. EQUI SUBSP. EQUI!!!
74
What species of strepto cause scarlet fever in humans, rheumatic fever, penumonia arthritis?
S. pyogenes
75
T/F. Necrotizing fasciitis AND myositis are caused by staphylo only.
False. Myositis only by strepto and necrotizing fasciitis by both staphylo and strepto.
76
Name three virulence factors of Strepto?
Capsule (hyaluronic acid), M protein (important in strangles), Streptokinase (plasminogen to plasmin: beneficial to cardiac patient)
77
What are three diagnosis of Strepto?
Culture swab, serology, PCR.
78
T/F. Staphylo recover spontaneously.
FALSE. STREPTO!!
79
Which bacterial genera are related to Strepto?
Enterococcus, PEptostreptococcus (obligate anaerobe), Abiotrophia (nutritionally fastidious)
80
How is S. canis transmitted? Who does it affect? Where does S. canis infect? Is it zoonotic?
Infection from vagina or umbilical vein (bacteremia); Kittens and puppies; **Skin and mucosal membrane**; Yes.
81
What is the BEST answer for incubatory period for S. equi? A. Shedding from affected sites. B. Nasal shedding 4-7d after. C. Nasal shedding for 6 weeks. D. Nasal shedding for \>5-7 months.
B. Nasal shedding 4-7 days after. A. CLINICAL C. CONVALESCENT D. LONG TERM
82
What does S. iniae cause in fish?
Septicemia
83
What is the name of disease that is caused by S. porcius?
JOWL ABSCESS OF PIGS
84
Who does S. Equi affect? How is it transmitted?
Weaned foals, yearlings; contact with horse shedding bacterium and contaminated environments.
85
What are the two important infections caused by S. equi in guttural pouch?
Guttural pouch empyema, guttural pouch chondroids
86
Killed streptococcal vaccine is used in which animals? when is live streptococcal vaccine used?
Preg. mare and foals; To stimulate immunity.
87
What is the BEST answer for incubatory period for S. equi? A. Shedding from affected sites. B. Nasal shedding 4-7d after. C. Nasal shedding for 6 weeks. D. Nasal shedding for \>5-7 months.
B. Nasal shedding 4-7 days after. A. CLINICAL C. CONVALESCENT D. LONG TERM
88
T/F. Enterococcus are facultative anaerobes, inhabits GI tract, nosocomial infections, persistent UTI, vancomycin/antimicrobial resistance, hard to treat.
True.
89
T/F. Micrococcus is pathogenic.
False. NON-PATHOGENIC.
90
T/F. Septicemia is seen in S. Canis and S. Suis ONLY within Strepto fam.
False. S. iniae too!!
91
What are the lipophilic spp. of Corynebacterium?
*C. pseudotuberculosis* and *C. urealyticum*
92
What are the non-lipophilic spp. of Corynebacterium?
*C. renale* group *(C. renale, C. cystiditis, C. pilosum),* and *C. diptheria*
93
Where can many Corynebacterium spp. be found?
**Soil and environmental source**; animal associated species are commensal on **skin and mucous membranes** (urinary tract)
94
Caseous lymphadenitis (*C. pseudotuberculosis*) is a contagious disease mainly in
1. Equine
2. Companion animals
3. Small ruminants
4. Avian
3. Small ruminants
* (sheep and goats, but cattle can also get infected)*
95
What is the pathological difference between lipophilic spp. and non-lipophilic spp. of Corynebacterium?
Lipophilic spp. cause pyogranulomatous lesions and non-lipophilic spp. cause pyogenic lesions (also toxic)
96
What is the most common Listeria species that is FACULTATIVE INTRACELLULAR? A. L. innocua B. L. ivanovii C. L. monocytogenes D. all of the above
C. L. monocytogenes
97
Where is the natural habitat for L. monocytogenes?
GI tract
98
What induces "winter-spring disease" in feedlot/housed ruminants? A. Feeding poor quality silage B. Having fermented sugars in the rumen C. Walking in circles D. Sexual activities
A. Feeding poor quality silage
99
T/F. L. monocytogenes are resistant to harsh environments and can live in a range of temperature.
True.
100
What is the main route to transmit Listeria?
Ingestion/Inhalation
101
What are three general infections that Listeria cause?
Encephalitis (ruminants by oral route), Abortion (focal hepatic necrosis in fetal liver), Septicemia (multifocal abscess in spleen and liver in monogastric neonates)
102
What does Listeria cause in poultry?
Septicemic listeriosis
103
What is the "circling disease" called?
Listeriosis
104
Abscess formation caused by caseous lymphadenitis (*C. pseudotuberculosis*) is _________ in goats and _________ in sheep
1. Internal
2. External
External in goats and internal in sheep
105
Caseous lymphadenitis (C. pseudotuberculosis) in horses is called
1. Colorado Strangles
2. Dry-Land Distemper
3. Pigeon Fever
4. All of the above
5. None of the above
4. All of the above
106
What is the mode of transmission for Pigeon fever (*C. pseudotuberculosis*) in horses?
1. Arthropod vectors (stable flies, horn flies, house flies)
2. Fomites
3. Soil
4. Skin abrasions
5. All of the above
5. All of the above
107
A veterinarian, Dr. Coryne, practicing in the west/midwest calls you and tells you that one of his patients (horse) has Pigeon fever. What signs and bacterial specie would you suspect?
Ulcerative lymphangitis of lower extremities and abscesses in the pectoral region (ventral abdomen); *Corynebacterium pseudotuberculosis*
108
A veterinarian, Dr. Coryne, practicing in the west/midwest calls you and tells you that one of his patients (horse) has Pigeon fever. What type of diagnostics did he perform to come to that conclusion?
*C. pseudotuberculosis*
* **Culture** purulent material (aspirate)
* **Serology**
* _Synergistic hemolysin inhibition (SHI) test_ that detects antibodies to phospholipase D exotoxin
* Colostral antibodies
* Be cautious of positive titers!
* Can also request a PCR
109
What do positive titers indicate when performing serology on *C. pseudotuberculosis*?
* Past resolved infections
* Recent exposure
* Recent vaccination
* Active lesions
*(that is why 1 titer is not sufficient; have to do multiple titers and see if there is an increase in value)*
110
A veterinarian, Dr. Coryne, practicing in the west/midwest calls you and tells you that one of his patients (horse) has Pigeon fever. It is his first case with this bacterial specie; what can you tell him about the treatment and control?
**Owner education is most important** (hygiene and management)! It is not considered a "curable" disease; culling is the best option, unless his patient has high genetic or emotional value. Treatment options include lancing and draining (sx), systemic antibiotics and intralesional antibiotics (Penicillin, Rifampin, Tulathromycin); vaccines are available but must strictly adhere to the label; next time, purchase animals from negative herds
\*A reportable disease in some areas; biosecurity practices important
111
Contagious Bovine Pyelonephritis (*C. renale*) is a disease that affects
1. Cow fetus
2. Young calves
3. Adult cows
3. Adult cows
112
What are the risk factors of Contagious Bovine Pyelonephritis (*C. renale*)?
* Trauma to bladder
* AI
* Parturition (urethra; causes ASCENDING infection)
113
How is Contagious Bovine Pyelonephritis (*C. renale*) transmitted?
* Contaminated bedding
* Venereal transmission
* Non-sterile OB instruments
114
What are the most important **virulence factors in anthrax**?
**CAPSULE & ANTHRAX TOXIN**
115
You suspect a cow with Contagious Bovine Pyelonephritis (*C. renale*), what are the signs (antemortem)?
Persistent temperature increase, loss of appetite and weight loss, painful urination and increase frequency, ammoniac odor of urine, acute abdominal pain (colic), decreased rumen contractions, decreased milk production
116
Where in the body does *Corynebacterium kutscheri* affect?
* _Lungs_: **suppurative pneumonia** (problem in lab animals)
* _Kidney, liver, heart_
* _Joints_: arthritic lesions
* _Lymph nodes_: hyperplasia
* **_Subcut_**icular abscesses
117
What is NOT a treatment for *B. anthracis*?
A. Antimicrbials given at the time when the symptoms are seen.
B. Localized forms may resolve without a treatment.
C. Penicillin, Tetracyclin, Doxycyline, Ciprofloxacin.
A. Antimicrbials given at the time when the symptoms are seen.
Antimicrobials effective if given early.
118
What are some postmortem findings for Contagious Bovine Pyelonephritis (C. renale)?
**Multifocal abscesses** in renal cortex, medulla, pelvis, **enlarged renal lymphnodes**, **uremia**
119
What is NOT a control of anthrax?
A. Quarantine herd (30 days following last death).
B. Use personal preotective equipment when handling contaminated animals/materials.
C. Vaccinate 8-12 days after antibiotic treatment.
D. Incineration or deep burial under layer of quickline.
E. Leave where the dead animals are right away.
E. Leave where the dead animals are right away.
120
How would you diagnose a cow with suspected Contagious Bovine Pyelonephritis (*C. renale*)?
Culture of urine or renal tissues
121
What does *Corynebacterium bovis* cause?
1. Keratitis in cows
2. Dermatitis in mice
3. Renal failure in cows
4. Pneumonia in cows
2. Dermatitis in mice
(*hyperkeratosis*)
122
What in Rhodococcus spp. promotes intra-macrophage survival and granuloma formation?
Lipid-rich cell envelope structures rich in mycolic acid
123
Rhodococcus equi is one of the main causes of what disease?
Foal pneumonia
## Footnote
*(foals 1-4 months old; exposure may occur very early in life, \<2 weeks)*
124
What is the appearance of lymph nodes (cross section) in those affected by *C. pseudotuberculosis*?
Distinctive lamellated "onion skin"
125
What is the pathogenesis of caseous lymphadenitis (*C. pseudotuberculosis*)?
Bacterial entry through skin and mucous membranes \> travel to lymph nodes and viscera \> replication in the phagocytes \> inflammation \> abscess formation
126
What are the virulence factors of *Corynebacterium pseudotuberculosis*?
* Exotoxin phospholipase D (damages endothelial cells)
* External lipid coat (protection from hydrolytic enzymes and phagocytes)
127
Where does *Rhodococcus equi* inhabit?
Soil, but virulence is maintained in horses
128
What are the virulence factors of *Rhodococcus equi*?
* **Capsule**
* **Virulence associated proteins (VAPs)** which are encoded on plasmids (promotes survival on non-activated macrophages)
* **Cholesterol oxidase (equi factor)** is a hemolytic factor
* Mycolic acid, teichoic acid, peptidoglycan, phospholipase C
129
At what age is Foal pneumonia (*R. equi*) less likely in horses?
\> 8 months old
130
What organs do Foal pneumonia affect (*R. equi*)? What are the lesions?
* _Lung_: 1-100 mm, coalescing, firm, caseonecrotic foci in the cranioventral lung lobes
* _GI tract_: ulcerative enterocolitis (usually over the Peyer's patches), ulcers in the large intestine (in over 50% of the animals)
* _Bronchial and mesenteric lymph nodes_: swollen, pyogranulomatous lymphadenitis
* _Bone_: osteomyelitis
## Footnote
*(img: bronchopneumonia in foals)*
131
What is the best method of diagnosis for *Rhodococcus equi*?
**Screening tests for early detection of disease or infection**
* High plasma fibrinogen
* Visual inspection (clinical signs)
* Rectal temperature, physical exam
* CBC
* Thoracic x-rays, ultrasounds in foals 1-3 months old
**Culture or PCR (for VAP A/B virulence factors) on transtracheal aspirate PLUS cytologic evidence of sepsis**
**Smears of affected tissues, transtracheal aspirates, bronchoalveolar lavages** (intracellular and extracellular clusters of cocci or rods seen)
132
Dr. Rhodo, a new equine vet, has diagnosed little PnuPnu (foal) with Foal pneumonia. How is he going to treat him?
Standard empirical treatment is a combination of _macrolide_ (erythromycin and clarithromycin) and _rifampin_ (synergy in vitro), BUT **treatment is expensive, prolonged** (1- \>3 weeks), and may even have **adverse effects**. Hyperimmune plasma and NSAID use is variable.
133
What is the best prevention method for Foal pneumonia (*R. equi*)?
**Early detection, treatment and environmental management**; hyperimmune plasma given on 1st or 2nd, 3rd or 4th day of life can prevent; azithromycin chemoprophylaxis treatment given shortly after birth has promise; cellular immunity is important
134
In gram stained smears, what type of bacteria forms long, branching filaments that tends to fragment into rods and cocci?
Nocardia
135
Pathogenic Nocardia spp. are strictly
1. Anaerobic
2. Aerobic
3. Capnophilic
2. Aerobic over a wide temperature range
136
Where does Nocardia inhabit?
Ubiquitous in soil and water
137
What are the 3 species of Nocardia?
* *N. asteroides* (most commonly isolated species in dogs and cats)
* *N. brasiliensis*
* *N. otitidiscaviarum*
138
What type of infection is seen in animals affected by nocardiosis (*N. asteroides*)?
Pyogranulomatous to suppurative
139
What is cutaneous nocardiosis (*N. asteroides*) in cattle called?
Bovine farcy
## Footnote
*(lymphangitis and lymphadenitis)*
140
What disease does *N. asteroides* cause in cattle and small ruminants?
Granulomatous mastitis
## Footnote
*(abortion in cattle, sheep, horses and swine with no other signals)*
141
What species cause fibrinopurulent pneumonia and pyothorax with sulfur granules in horses (Nocardia)?
* *N. asteroides*
* *N. brasiliensis*
142
What kind of culture does *Nocardia asteroides* grow on?
* Selective and non-selective blood agar
* Sabouraud-dextrose
## Footnote
*(may produce aerial mycelia and carotenoid pigment)*
143
Nono the dog came into your vet clinic with pyogranulomatous infections on the skin of its thorax. You suspect *Nocardia asteroides* because Nono also loves playing in dirt and water. What diagnostic tests would you perform?
Culture, acid-fast stain, ID
144
After diagnostic tests, Nono the dog was confirmed to have *N. asteroides*. What is the treatment and control?
Susceptibility varies; single treatment with **trimethoprim/sulfa** is effective for many species; if it was a **life-threatening** systemic infection, a **combination of aminoglycosides (amikacin) and carbapenem (imipenem)** would best the best empirical choice.
THIS DISEASE IS DIFFICULT TO CONTROL
145
These gram positive organisms came from a bronchial lavage from a foal. What bacterial species is most likely?
*Rhodococcus equi*
146
This image was taken postmortem from a foal who also had a pyogranulomatous lung infection. What bacterial species is most likely?
*Rhodococcus equi*
147
What is the most common staphylococcus isolate from dogs?
*Staphylococcus pseudintermedius*
148
In this acid-fast stained smear, long, branching filaments can be seen. What bacterial species is most likely?
Nocardia
149
Staphylococcal enterotoxin exerts its pathogenic effect by
1. Binding indiscriminately to the T cell receptor and Class II MHC molecule
2. Binding to receptor using the B unit activation of an enzyme using the A unit
3. Binding to the CD 14 receptor and activating macrophages to release TNF alpha
1. Binding indiscriminately to the T cell receptor and Class II MHC molecule (superantigens)
150
A bacteria which uses host actin filaments to travel between cells
1. *Listeria monocytogenes*
2. *Erysipelothrix rhusiopathiae*
3. *Bacillus anthracis*
4. *Streptococcus iniae*
1. *Listeria monocytogenes*
151
Which of the following is incorrect about listeriosis in ruminants?
1. Outbreaks occur after feeding soiled silage
2. Encephalitis and neurological signs occurs after the organism enter through the wounds in the buccal mucosa
3. Generally disease occurs in the winter months
4. Hepatic necrosis is the main lesions in adult animals
4. Hepatic necrosis is the main lesions in adult animals
## Footnote
*(only in young animals and monogastrics)*
152
T or F. Toxin and capsule are required for the virulence of Bacillus anthracis
True
153
T or F. Capsule of Anthrax bacilli is composed of a polysaccharide
False
154
McFadyean staining reaction is used for detecting
1. LPS of anthrax bacilli
2. Capsule of anthrax bacilli
3. Fimbriae of anthrax bacilli
4. Endospore of anthrax bacilli
2. Capsule of anthrax bacilli
155
T or F. In avirulent forms of *Bacillus anthracis* presence of toxin is essential for protective immune response
True
## Footnote
*(capsule by itself = no protective response)*
156
T or F. Anthrax is a contagious disease
False
## Footnote
*(it is an infectious disease; _contagious disease_- transmission from person to person quickly)*
157
Caseous lymphadenitis in sheep is caused by:
1. *C. pseudotuberculosis*
2. *C. renale*
3. *C. bovis*
4. *C. ovis*
*1. C. pseudotuberculosis*
158
T or F. Positive Antibody titers to phospholipase D exotoxin of *C. pseudotuberculosis* is diagnostic for Caseous lymphadenitis
False
## Footnote
*(have to be careful of positive titers!)*
159
Which one of the following process is a least likely virulence mechanism in bacteria?
1. Bacterial movement using flagella
2. Bacterial attachment using fimbriae
3. Biofilm production and attachment to surfaces
4. Bacterial protein production by ribosomes
4. Bacterial protein production by ribosomes
160
Which gram positive rods are associated with **pyogenic infections in livestock?**
A. Actinomyces only
B. Actinomyces, Actinobaculum only
C. Actinomyces, Actinobaculum, Trueperella
C. Actinomyces, Actinobaculum, Trueperella
161
T or F. *Rhodococcus equi* is an obligate intracellular pathogen
False
## Footnote
*(facultative intracellular pathogen)*
162
Which of the following statement is incorrect?
1. MIC is the lowest concentration of antimicrobial agent which can inhibit the growth of bacteria
2. Published break point are required for interpretation of AST results
3. MIC can be measured in E-Test
4. MIC can be accurately measured in Disk diffusion test (Kirby Bauer tests)
4. MIC can be accurately measured in Disk diffusion test (Kirby Bauer tests)
## Footnote
*(can only extrapolate with the data)*
163
Amphotercin, Chloramphenicol, Tetracycline, Erythromycin, Neomycin, Streptomycin, and Gentamycin are antibiotics derived from which species of bacteria?
A. Trueprella
B. Actinomyces
C. Actinobaculum
B. Actinomyces
164
T or F. Toxin and capsule are required for the virulence of *Bacillus anthracis*
True
165
What disease will be in the top of your differential diagnosis list for a horse presented with this lesion?
1. Pyoderma
2. Strangles
3. Anthrax
4. Lymphadenitis
2. Strangles
166
T or F. *Actinomyces bovis* can be acid fast positive by Kinyoun’s staining protocol
False
## Footnote
*(they do not have mycolic acid)*
167
What types of anaerobes are there? (spores, gram)
* Spore forming and non-spore forming
* Spore forming gram positive (Clostridia)
* _EXCEPT_ *Clostridium piliforme* is a gram NEGATIVE Clostridium that causes Tyzzers disease in lab animals
* Non spore-forming gram positive and negative
168
T or F. Clostridium spp. are endospore forming Gram positive rods
True
## Footnote
*(img: subterminal endospore)*
169
What are the 3 types of Clostridium?
1. Neurotoxic
2. Histotoxic and invasive
3. Enteric/Enterotoxigenic
170
Where does Clostridium inhabit?
Soil and intestines of animals
(also feces in *Clostridium tetani*)
171
What are the virulence factors that all pathogenic Clostridia produce?
Bacterial protein toxins or extracellular enzymes
172
\_\_\_\_\_\_\_\_\_ provides an initial opportunity for Clostridium to grow, is the host response to many clostridial toxins, and facilitates the rapid spread of infection through the body.
Necrosis
173
What disease does Clostridium tetani cause?
Tetanus
174
What 2 species of Clostridium produce neurotoxins?
1. *Clostridium tetani* (tetanospasmin)
2. *Clostridium botulinum*
175
Where does *Clostridium tetani* like to grow (mode of infection)?
Contaminated wounds
176
What type of paralysis does *Clostridium tetani* cause?
1. Spastic paralysis
2. Flaccid paralysis
3. None
1. Spastic paralysis
## Footnote
*(toxins enter motor nerves \> retrograde transport via motor nerves, spinal cord, or blood \> enters neuromuscular endings of motor nerves \> prevents the release of NT glycine and GABA \> spastic paralysis)*
177
How do you control S. equi?
A. Quarantine/isolate
B. Hygiene, disinfect
C. Bacteriological screedning to detect
D. All of the above
D. all of the above
178
What is tetanus called in horses?
Wooden Horse Syndrome
179
A dog comes into your clinic with spastic paralysis and you put tetanus on your DDx. What diagnostic methods would you use to confirm this?
* History of recent wound
* Clinical signs
* Gram stain
* Serology, histology, and culture are all not useful
180
How do you treat an animal with tetanus (*C. tetani*)?
* _Antitoxin_ from horse serum to neutralize UNBOUND toxin (IV or IM), but anaphylaxis is possible
* _Antimicrobial_ (to stop toxin production)
* Surgical debridement of wounds
* _Hyperbaric oxygen_ (to stop toxin production)
* _Supportive care_ (reduce external stimuli, sedatives, muscle relaxants)
181
How do you control tetanus (*C. tetani*)?
* _Toxoid immunization_ (man, horses, small ruminants)
* Post exposure prophylaxis (booster in man and horses)
* Wound management (both vaccinated and unvaccinated animals)
* Rational antimicrobial therapy
* Aseptic techniques during surgery, proper sterilization
182
What disease does *Clostridium botulinum* cause?
Botulism
183
How is botulism transmitted?
1. Inhalation
2. Sexually transmitted disease
3. Ingestion
4. Arthropods
3. Ingestion
## Footnote
*(food intoxication/poisoning; toxin is absorbed and distributed in the bloodstream)*
184
What type of paralysis does *Clostridium botulinum* cause?
1. Spastic paralysis
2. Flaccid paralysis
3. None
2. Flaccid paralysis
185
*Clostridium botulinum* inhibits which neurotransmitter to be released?
1. GABA and glycine
2. Acetylcholine
2. Acetylcholine
186
Where can *Clostridium botulinum* toxins be found?
1. Soil
2. Spoiled food/canned food
3. Water
4. Rusty nails
2. Spoiled food/canned food
187
How many grams of dried flesh with botulinum toxin does it take to kill a cow?
1. 1 gram
2. 10 grams
3. 100 grams
4. 1,000 grams
1. 1 gram
188
What kind of symptoms can be seen in a human with botulisim?
Cranial nerve disfunction (double vision, dysphagia, speech disfunction, etc)
189
What signs can be seen in an animal with botulism?
Symmetrical flaccid paralysis of muscles, hind limb paralysis, recumbence, respiratory failure (diaphragm)
190
Aquatic birds in northern states can get avian botulism from eating what?
1. Adult flies
2. Fly larvae
3. Maggots
4. Plants
3. Maggots
## Footnote
* (toxin production takes place in decaying animal carcass \> maggots concentrate toxin \> birds eat maggots \> bird dies \> cycle repeats)*
* (img: botulism infected bird with protruding nictitating membrane)*
191
Botulism in chickens is also called \_\_\_\_\_\_\_\_\_
1. Limberneck
2. Flaccineck
3. Dropneck
4. Rubberneck
1. Limberneck
192
How is botulism diagnosed?
* Toxin demonstrated in serum (laborious and $$$)
* Toxin demonstrated in food/stomach with MALDI-TOF (mouse bioassay/neutralization test-GOLD STANDARD)
Toxin AND bacteria are select agents (very potent)
193
How can an animal with botulism be treated?
* _Antitoxin_ (affects UNBOUND toxin only; IV or IM)
* Only useful is the animal is still actively absorbing the toxin
* Once the toxin enters blood stream, it is bound by receptors
* _Therapeutic drugs_ to enhance cholinergic NT acetylcholine release
* _Supportive care_ (fluids, respiratory maintenance, feeding/elimination functions)
194
How is botulism controlled?
* _Toxoid immunization_ in high risk animals (farmed mink)
* Most animals not routinely vaccinated
* _Avoid feeding suspect foodstuff_ (canned food, spoiled food)
195
What are the 3 species of _histotoxic_ Clostridia?
* *C. chauvoei*
* *C. septicum*
* *C. novyi*
## Footnote
*(they are invasive (muscles) and less potent toxins)*
196
What diseases do each histotoxic Clostridia cause?
* *C. chauvoei*?
* *C. septicum*?
* *C. novyi*?
Necrotizing myositis
* C. chauvoei: Black leg in cattle, sheep, pigs
* C. septicum: malignant edema, Braxy, necrotic dermatitis (chicken) in cattle, sheep, pigs, chicken
* C. novyi (A, B, C): Gas gangrene, Black disease (necrotic hepatitis)
DON'T GET BLACK LEG DISEASE AND BLACK DISEASE CONFUSED
*(img: necrotic myositis)*
197
What process occurs in tissues of _histotoxic_ Clostridial diseases?
Toxins elaborate during growth \> tissue destruction \> fermentation of muscle glycogen \> gas accumulation (hydrogen/**methane**) \> metabolic end produces (organic acids, amines) \> SMELLY!
198
T or F. Mechanically deposited endospores (from histotoxic Clostridia) that leave the GI tract may remain dormant in the body for extended periods of time.
True
(endogenous)
199
Where does Clostridium chauvoei inhabit?
1. GI tract
2. Soil
3. Spoiled food
4. Answers 1 and 2
5. All of the above
4. Answers 1 and 2
200
What is the common outcome of Black leg (*C. chauvoei*)?
1. Fast recovery
2. Long treatment to recovery
3. Sudden death
4. Paralysis
3. Sudden death
201
What is Black leg disease (*C. chauvoei*)?
* Disease of cattle and sheep
* Wound infections shearing cuts, docking, crutching, or castration in sheep
* Fever, anorexia, depression, lameness
* **Emphysematous swelling** (commonly affects heavy muscles); hemorrhagic
* Endogenous infections in cattle (**well-nourished young cattle**)
* Cellulitis, necrotic myositis
* Crepitus (hip, shoulder, chest, back, neck)
* Sudden death common (100% fatality)
## Footnote
*(img: hemorrhagic and emphysematic lesion)*
202
What is the common cause of traumatic damage in Black disease (*C. novyi* type B)?
Liver fluke
## Footnote
*(spores in the intestine reach liver and remain dormant in Kupffer cells \> traumatic damage by liver fluke \> anaerobic conditions \> germination of spores)*
203
Explain **malignant edema** caused by *C. speticum.*
* Affects all species and ages
* Dormant spores in muscles
* Caused by IM injections in horses, shearing docking and lambing in sheep, traumatic parturition and castration in cattle
* Local exotoxins cause excessive inflammation \> edema \> necrosis \> gangrene
## Footnote
*(img: muscle necrosis)*
204
Explain braxy caused by *C. septicum*
* In sheep
* Highly fatal infection (toxemia and inflammation of the abomasal wall)
* Malignant type
205
What is the best diagnostic method for necrotic myositis (histiotoxic Clostridia)?
1. Culture
2. Direct Fluorescent antibody staining tests
3. PCR
4. MALDI-TOF
2. Direct Fluorescent antibody staining tests
## Footnote
*(DON'T WASTE TIME!!; C. septicum and C. novyi can also be a normal post-mortem invader)*
206
How is necrotic myositis treated (histiotoxic Clostridia)?
1. Antimicrobial treatment with penicillin if given early
2. Hyperbaric oxygen
3. Surgical debridement/amputation
Control with routine vaccination of farm animals (multicomponent bacterin/toxoids)
207
What are the 3 species of enteric Clostridium?
1. *C. perfingens*
2. *C. difficile*
3. *C. spiroforme*
208
What type enterotoxemia causes Pulpy kidney disease (overeating disease) in small ruminants?
1. A
2. B
3. C
4. D
4. D
209
What are the signs and symptoms of sheep with *C. perfringens* type D enterotoxemia?
* Fluid-distended intestine with hemorrhagic petechiae on serosal surface
* Neurological problems (like Listeria)
* Edema and malacia detected in the basal ganglia and cerebellum of lambs (focal encephalomalacia, a common postmortem finding)
* Rapid postmortem autolysis of KIDNEYs (Pulpy kidney deases)
210
How is *C. perfringens* diagnosed?
* Smear to see gram + rodes (microscope/relative #)
* **Culture (determine toxin genotype of isolates)**
* Toxin detection in intestinal contents (not widely available)
* Biological assay (mouse neutralization; $$$, time)
* Serological tests for toxin antigen (cpe ELISA, for dogs)
211
How is an animal diagnosed with *C. perfringens* enterotoxemia treated?
* Hyperimmune serum (if available and given early)
* Antimicrobial therapy (NOT for GI diseases)
* Just supportive therapy can work
Control with routine immunization of farm animals with toxoid/bacterins; avoid sudden diet changes or stress that might change the GI flora or damage GI mucosa
212
T or F. *Actinomyces bovis* can be acid fast positive by Kinyoun's staining protocol
False
213
What type of culture would you request from a dog with a sublumbar abscess?
Aerobic and anaerobic
## Footnote
*(Actinomyces hordeovulnaris)*
214
Which of the following feature help in the identification of *Dermatophilus congolensis* infection in cattle?
1. Scabby lesions
2. Presence of gram positive coccobacilli in the smear
3. Tram track appearance of the organism in the stained smears of scabs
4. Presence of gram variable filamentous bacteria in the smear
3. Tram track appearance of the organism in the stained smears of scabs
215
T or F. *Trueperella pyogenes* is a common bacterial isolate from pyogenic lesions of internal organs in cattle
True
216
Which of the following agent disease pair is incorrect?
1. *Actinobaculum suis*- pyelonephritis in swine
2. *Corynebacterium bovis*- pyelonephritis in cattle
3. *Actinomyces bovis*- Lumpy Jaw in cattle
4. *Dermatophilus congolensis*- Rain Scald in horses
2. *Corynebacterium bovis*- pyelonephritis in cattle
## Footnote
*(Corynebacterium renale)*
217
What species does Clostridium difficile enterocolitis affect?
Man, horse, pig, dog, cat, lab rodents, etc.
218
What organs does *Clostridium difficile* enterocolitis affect?
Colon and cecum
* Pseudomembraneous colitis \> diarrhea
219
What are the risk factors of *Clostridium difficile* enterocolitis?
Recent antibiotic use, increased-age and hospitalization (nosocomial)
## Footnote
*(endospores are usually in low inumbers in the normal intestine, but risk factors allow the organism to spread)*
220
What does dysbiosis mean?
disruption in the normal flora
221
Toxin A from Clostridium difficile is a
1. Enterotoxin
2. Neurotoxin
3. Histotoxin
4. Cytotoxin
1. Enterotoxin
(causes fluid loss and affects G proteins)
222
Toxin B from Clostridium difficile is a
1. Enterotoxin
2. Neurotoxin
3. Histotoxin
4. Cytotoxin
4. Cytotoxin (in vitro)
(similar mechanism of action, destroys cells more rapidly, acts synergistically with Toxin A; not many strains produce Tox B only)
223
Clostridium difficile is a
1. Obligate anaerobe
2. Obligate aerobe
3. Facultative anaerobe
4. Facultative aerobe
1. Obligate aerobe
224
Duffy, a dog, had received an injection of antibiotics last week and came into your clinic presenting with diarrhea. Because you put Clostridium difficile on your DDx, what diagnostic methods would you use?
Culture and direct toxin detection (tissue culture assay for Tox B with specific Ab neutralization, ELISA for Tox A or Tox A/B)
225
How would you treat Clostridium difficile diarrhea?
* Mainly supportive therapy (electrolytes and fluids)
* STOP ANTIBIOTICS
* Clindamycin should NOT be used in horses
* **Antimicrobials in severe cases**
* Probiotics **(Lactobacillus, Saccharomyces replaces flora)**
* Avoid anti-diarrheals **(accumulates toxin)**
* Toxin adsorbent **(adsorbs meds also)**
226
What species does *Clostridium spiroforme* affect?
Rabbits
## Footnote
*(4-8 week old)*
227
What disease does *Clostridium spiroforme* cause?
Explosive diarrheal disease (enterotoxemia)
## Footnote
*(from antibiotic use)*
228
What toxin does *Clostridium spiroforme* causes?
iota toxin
229
What antimicrobials should not be used in rabbits?
Lincomycin, Clindamycin, and erythrocyin
(they induce Clostridium-related enterotoxemia *(C. difficile and C. spiroforme)*
230
*Clostridium piliforme* is
1. Gram positive, non-spore forming
2. Gram positive, spore forming
3. Gram negative, non-spore forming
4. Gram negative, spore forming
4. Gram negative, spore forming
## Footnote
*(an exception to gram positive spore forming bacteria!)*
231
What type of disease is Tyzzer's disease (*Clostridium piliforme*)?
acute, fatal diarrheal disease of lab animals with associated focal liver necrosis; diagnosed post-mortem
232
Clostridium piliforme is a _________ pathogen.
1. Facultative intracellular
2. Obligate intracellular
3. Extracellular
2. Obligate intracellular pathogen
## Footnote
*(lives in hepatocytes; "hay stack" appearance)*
233
What are examples of gram positive cocci, non-sporeforming anaerobes?
* Peptostreptococcus
* Sarcina
234
What are examples of gram positive rods, non-sporeforming anaerobes?
* Propionibacterium
* Bifidobacterium
* Actinobaculum
* (Lactobacillus, Actinomyces)
235
What are examples of gram negative cocci, non-sporeforming anaerobes?
* Veillonella
* Ruminococcus
236
What are examples of gram negative rods, non-sporeforming anaerobes?
* **Fusobacterium**
* **Bacteroides**
* **Dichelobacter**
* **Porphyromonas**
* **Prevotella**
## Footnote
*(most commonly seen)*
237
What are examples of gram negative spirochetes, non-sporeforming anaerobes?
* Treponema
* Brachyspira
* unclassified
238
Where are non-spore forming anaerobes commensal on?
Mucous membranes and skin
239
What do non-spore forming anaerobes require to grow in media?
Vitamin K, hemin and other growth factors
(grow slower than common aerobic and facultative anaerobic bacteria)
240
How can non-spore forming anaerobes be clinically identified?
Morphology, antimicrobial susceptibility pattern, biochemical tests, products of fermentation, and molecular testing
241
What are some virulence factors for non-spore forming anaerobes?
Not well characterized in all species (adhesins, extracellular enzymes, LPS), but some are:
* Leukotoxins (Fusobacterium necrophorum)
* Fimbriae, proteases (Dichelobacter nososus)
* **Catalase and superoxide dismutase** (protects some from oxygen toxicity)
* **Synergistic activities** (tissue damaging factors that establish niche for second organis)
242
What are signs consistent with anaerobic infections?
* Foul smelling discharges
* Gas in tissues or discharges
* Necrotic tissue, abscesses
* Pyogranulomatous lesions with granules
* Infections near or on mucous membranes
* **Infections not responding to aminoglycosides (DO NOT USE AMINOGLYCOSIDES FOR ANAEROBIC ORGANISMS AND FUNGAL INFECTIONS)**
* Disease in the absence of significant growth in aerobic cultures
243
What diseases does *Fusobacterium necrophorum* cause?
* Affects multispecies, rumen
* Foot rot
* Hepatic abcsesses
* Calf diphtheria (throat infections)
(anaerobic, non-spore forming gram negative rods)
244
What diseases does *Dichelobacter nodosus* causes?
Foot rot in sheep
(anaerobic, non-spore forming gram negative rods)
245
What does *Porphyromonoas* spp. produce?
(anaerobic, non-spore forming gram negative rods; ruminants)
Most produce black iron porphyrin pigments
246
What does Prevotella spp. produce?
Some produce black iron porphyrin pigments
(anaerobic, non-spore forming gram negative rods; ruminants)
247
What type of bacteria is *Bacteroides fragilis*?
Anaerobic, non-spore forming gram negative rods; ruminants
248
How do you control diseases caused by non-spore forming anaerobes?
Hard to treat and control!
* Keep feet dry
* Avoid mechanical injury
* Parasite control
* Routine immunizations
* Good nutrition
* Dental prophylaxis
* Vaccines in sheep and cattle (*Fusobacterium necrophorum*); sheep (*Dichelobacter nodosus*)
249
How do you diagnose non-spore forming anaerobic diseases?
Culture, PCR (?)
* ID requires specialized methods and is often incomplete
* Biochemical tests kits
* 16S rRNA gene sequencing
* MALDI-TOF-MS
* Susceptibility testing specialized and only standardized for few genera (Bacteroides and Clostridium)
250
How do you treat infections/diseases caused by non-spore forming anaerobes?
* Remove necrotic tissue, oxygenate
* Antiseptic foot baths
* Antimicrobials: penicillin, **metronidazole**, clindamycin (not for horses and rabbits), chloramphenicol, doxycycline
* AMINOGLYCOSIDES, SULFONAMIDES NOT EFFECTIVE!!
251
T or F. Anaerobic infections are mostly endogenous, localized (oral/GI tract), and mixed infections (polymicrobial).
True
