L2: Actinomycetes

Tell me more about Polymicrobial (mixed) infections

-he discussed this with the truperella earlier -anaerobes like mixed infection so contamination with feces, feces contains both-facultative anaerobe & strict anaerobe

What is interesting about the mature zoospores?

-interesting: these little zoospores are chemotactic for CO2 =when you have lesions you suspect ot have D. congolensis, put that lesion on container of liquid (PBS) then put the material in or in a tube then in a CO2 incubator, so zoospore that come out of the material sense the CO2 gradient & go up at the liquid air interface. Catch them then grow them= enrichment procedure

What is the therapy for anaerobes?

-remember it's pus frequently & is deep so you have to open the wound: 1. Surgery (drainage) =more oxygen you can bring in the wound, better change to eliminate obligate anaerobe to allow wound to close & heal 2. Antibiotics (resistant to aminoglycosides, old fluoroquinolones)

Another bacteria that he doesn't want to tell us too much about except that it's in pigs: Actinobaculum suis (Actinomyces suis, Eubacterium suis, Corynebacterium suis) 1. What conditions does it need? 2. What does it cause?

1. Anaerobe (strictly!) 2. Necrotic purulent pyelonephritis & cystitis in swine - really typical to find this bacteria. if you spin their urine, you'll find these little bacteria -penicilin susceptible if you don't already have big absesses

How does an infection typically happen?

1. Step on nail -> goes thru skin 2. take nail out, skin closes on top of it =perfect potential for infection 3. When you walk on nail, think Tetanus (anaerobe-Claustrydium tetani)

What is another Actinomyces that is found in dogs, but also humans?

Actinomyces viscosus

If anything has pus, then what should you think?

Actinomycetes

Gram + There are a few gram + anaerobic streptococci. tell me where you'd find them and with what

Anaerobic streptococci 1. Cause Abscess 2. Cause Mastitis in cows 3. Mixed with other anaerobes ****all yellow**

You have mastitis in cow. do gram stain, see chains of cocci & they don't grow. why? that's strep which usually grows

b/e you can have mastitis with anaerobic streptococci =in little chains

Nocardia asteroides: what problem in humans?

brain problems by invading endothelial cells there. -not frequent but not rare

Dog - Thoracic granuloma - Nocardia How do they stain?

gram +

What do Actinomyces bovis look like on gram stain?

gram +

One thing he wants us to really think: don't use aminoglycosides such as (gentamicyin?) or old fluoroquinolones because vets tend to give cypro with anything but

it doesn't work with anaerobes

What does Corynebacterium mean?

kidney form (I thin khe said that?)

Recall what are major bacteria in feces:

lots of E. coli but then near the end of large intestine, more and more anaerobes than coliforms (100s-1000sx more anaerobes)

Dichelobacter (old name: Bacteroides) nodosus Tell me about it where do you have problems ***yellow&&

problems in big sheep herds like australia, new zealand, some states 1. Obligate parasite of hooves of ruminants (short life in soil) 2. Causes disease called Contagious footrot in sheep - predisposing factors (humidity=helps bacteria survive & multiply in hoof, trauma) 3. Frequently found with triparella, A. pyogenes, F. necrophorum, etc... 4. Vaccinates based on Fimbriae (antigenic variability: multivalent vaccines) 5. Heat-stable protease (= keratinase) =makes sense b/e have to survive in, & degrade hoof 6. Penicillin-susceptible 7. Trimming of the hooves, disinfectant baths -improtant to trim horse foot & sheep hoof

Whenever you have mixed anaerobic infections, what do you see?

see mixed fusobacterium, triparella, & frequently these little gram - bacteria. If you look at feces under microscope(gram stain), see lots of these little rods. ***Mixed with other anaerobes; Cause: oral infections, aspiration pneumonia, pyothorax (cats), castration wounds, umbilical infections (b/e of way it was cut), sepsis (i.e. not enough colostrum) ****

Actinomycosis

stupid name of mycosis but it's not a fungi, it's a bacterium. it's a prokaryote not a eukarote which fungi is

While you might think of the oral cavity as aerobic, what?

there are lots of places that are anaerobic i.e. in the gingiva, etc, crevis of tonsils, hiding places in oral cavity

When might a farmer cause mastitis?

tubes of antibiotic then something is contaminated, pushes some in & end with horrible mastitis. milk looks like pus + honey so it's not milk anymore

When does Streptothricosis occur?

when rain etc something helps the bacteria procreate in the lesion So, 1st little lesion-> little humid, rainy, housed in rain+ problem wth Streptothricosis -> bacteria grow more

Many of these little gram - bacteria have been studied for oral microbiology. What virulence factors do they have? In white, not yellow

1. Capsule - activates complement, chemotactic for leukocytes 2. Proteases - collagenase, IgA protease 3. Nontoxic LPS =on lipid A: less chains=less endotoxic 4. Some - enterotoxin, hemolysin 5. Superoxide dismutase, catalase (decreased susceptibility to O2) 5. Therapy - metronidazole, clindamycin; antibiotic-resistance (penicillin!) -while many anaerobes are penicillin senstiive, many are not.=not always best way to treat

Other information on Trueperella from previous flash card slide but not in yellow so maybe not as important: 1. Does it grow in anaerobic or aerobic conditions? 2. What are virulence fators?

1. Facultative anaerobe -can grow aerobically & anaerobically. prefer oxygen if available 2. Cytolysin (hemolysin, pyolysin), extracellular-matrix binding proteins, neuraminidases, fimbriae, proteases; invades epithelial cells and survive in MØ (how?no one knows)

Fusobacterium necrophorum 1. Are they gram + or - 2. What do they look like on gram stain?

1. Gram - 2. Make long filaments: Look like beaded filaments =see this & you know you have F. necrophorum (lots of different Fusobacterium in humans)

Describe ACTINOMYCETES =family of bacteria -think of expansion of bacteria 1. Morphology? 2. When you think Actinomycetes, what should you think?

1. Gram positive rods and branching filaments -similar rods to previously learned bacteria but now they branch 2. Chronic purulent (pus) and granulomatous infections 3. Difficult to treat with antibiotics

Non yellow stuff from Tell me about Actinomyces viscosus

1. Have Fimbriae -studied a lot by dentists & oral microbiologists 2. Microscopic diagnosis: gram stain (Gram + little rods), immunofluorescence

1. What virulence factors do these Fusobacterium have? 2. Treatment & preventation/control? yellow stuff in stared but leukotoxin & LPS & vaccines in white

1. Leukotoxin (hemolysin) =see zone of hemolysis ii. LPS (can be decorated with phosphocholine- to prtect against host attacks by macrophages aka to look like a host cell) 2. i. *Penicillin-susceptible*, no effective vaccines ii. *Hygiene - survives for months in humid bedding or soil* -thrust in horse frequently linked with bad hygeine

What happens in polymicrobial infections?

1. Little bit of oxygen left 2. Facultative anaerobe grabs that b/e they prefer oxygen fermentation or oxygen independent respiration 3. These facultative anaerobe use the oxygen completely. As soon as that's done, the obligate anaerobe wake up if not killed yet & cause a problem 4. Now you have completely anaerobic environment 5. Also when you have a lesion, one important thing is: essentially interfere with normal vascularization of tissue where lesion is =not easy oxygen coming in there =additional problem So, infection with facultative anaerobic bacteria is a synergistic process to maintain a lower redox potential

What should you remember about Fusobacterium necrophorum

1. Mixed infections with A. pyogenes, Bacteroides spp., etc.. 2. Together, cause disease called Necrobacillosis =necrosis 3. Also have, Phlegmonous and ulcerative necrotic stomatitis in cattle and swine i. fights between pigs - bull nose) ii. calf diphtheria -more common in old days -people used to restrict nutrients to calf so meat would look better so calves would lick metal & get infection that way 4. Rumenitis-2 origins: i. Rumen acidosis from a grain rich diet, leading to ulceration of rumen & liver abscess b/e rumen filled with lots of anaerobes invovles with cellulose degradation (+ protozoa)=same type of anaerobes in large intestine (i think?) (grain-rich diet, rumen acidosis, ulceration), liver abscess

Trueperella pyogenes (Old names that we don't have to know it's just in case we see it in a textbook: Actinomyces pyogenes, Corynebacterium pyogenes, Arcanobacterium pyogenes) 1. Where is it found 2. What does it cause? 3. What else do you see with this type of infection? 4. What is the therapy?

1. Mucosal (nasal and oropharyngeal) flora of ruminants and swine (+ also horse & vaginal) 2. Chronic purulent infections -ex: mastitis, endometritis, pneumonia, endocarditis, arthritis, etc. 3. Opportunist, polymicrobial infections (+ anaerobes) -frequently found in mixed infections typically with anaerobes -> later he will tell us why we have a facultative anaerobe with an anaerobe (synergism) 4. Therapy - drainage, penicillin (b/e it's pus & granuloma so need surgery)

Now we will switch He will discuss anaerobes in general, even though it's titled nonspore forming anerobes-it's about anaerobes in general: Tell me about anaerobes in genearl: 1. Where are they? 2. Tell me about infections 3. Explain the polymicrobial infections 4. What type of anaerobic lesions do you see? NONSPORE-FORMING ANAEROBES

1. Oral and gut flora of animals and humans 2. Related to what he said he would tell us about later: ***Infections require two simultaneous events i. trauma of deep tissues & ischemia = decreased O2 tension (so need event to take oxygen away) ii. fecal contamination (anaerobes), bites 3. Polymicrobial (mixed) infections, with facultative anaerobic bacteria, synergistic process (maintenance of a low redox potential) 4. Abscesses, gingivitis, peritonitis, tissue necrosis -produce gas with strong smells

Actinomyces bovis 1. Where is it found? 2. What does it cause?

1. Oral flora (cattle) Anaerobe 2 "Lumpy jaw" in cattle - traumatic lesions in the oral cavity leading to this disease: chronic granulomas involving bones(≠ actinobacillosis); -fistulation through the skin or oral mucosa 3. Microscopy of sulfur granules - 10% NaOH (clubs: proteins & CaPO4), gram stain 4. Therapy - drainage, iodine solutions, penicillin =same thing, surgery, general treatment with penicillin -beta dine

Tell me about Actinomyces viscosus 1. where is it found? 2. What conditions does it need? 3. What does it cause? 4. Therapy

1. Oral flora of dogs, humans =problem in dentistry ie. anaerobic problems & gingivitis 2. Facultative anaerobe 3. Actinomycosis in dogs and cats - chronic pyogranulomatous infections under the skin or in body cavities (in cats more than dogs, see pyothorax) 4. Therapy - drainage, penicillin =general rule

What are other problems with Fusobacterium necrophorum?

1. Pericarditis (foreign body) -piece of metal swallowed by cow can go into reticulum -> from there, can go to heart or liver =cause hepatitis or pericarditis -> heart then lots of bacteria -typically Fusobacterium mixed infection 2. Footrot in cattle =Interdigital phlegmonous infections (ulceration) 3. Thrush in horses =walk frequently on feces & feces filled with anaerobes so if any lesions where bacteria can go in & produce anaerobic bacteria =problem

How do you see the sulfur granules?

1. Put pus on slide with 10% NaOH 2. Smash a bit & Look under microscope 3. See clubs that mineralize calcium phosphate 4. In middle, see branching actinomyces bovis

what is the incredible way the Dermatophilus congolensis divides?

1. Start with a zoospore =unique cell with flagella 2. Removes flagella, creates a germ tube 3. Begin to make transverse/lateral divisions 4. Starts to divide vertically =longitudinal septa created 5. When enough separation going in all direction, end up with closed little areas 6. then end up with round cell that undergoes primary fission & you get cocci of 0.3-0.4 um 7. Then, they're released with the flagella as mature zoospores & can move around

In yellow for Dermatophilus congolensis: 1. What disease does it cause? In who? 2. What are virulence factors? 3. What is the therapy?

1. Streptothricosis (aka dermatophilosis) -in ruminants, horses (dogs, cats, humans) =exudative dermatitis aka causes a lesion in the skin i. " rain rot" or "rain scald" in horses =great practical names ii. "lumpy wool", "strawberry foot rot" in sheep 2. Virulence factors - extracellular proteases (keratinase which makes sense b/e has to grow in the skin) -not much is known 3. Therapy - i. hygiene ii. iodine (i.e. betadine) iii. penicillin+streptomycin -Streptothricosis is the more common name

Next bacterium Nocardia asteroides 1. Where is it found?? 2 & 3. What conditions does it live in? 4. What does it cause?

1. Ubiquitous (soil), 2. Aerobe, produce mycolic acid 3. Facultative intracellular pathogen -b/e of that, want to induce cell-mediated immunity but can go around this 4. Chronic, granulomatous fistulous infections in the oral cavity, the subcutis and internal organs =similar to A. viscousus in dogs i. (lungs - aspiration pneumonia) ii. mastitis (iatrogenic)

Tell me about Fusobacterium necrophorum

1. Very involved in vet med infections of cattle, pigs, horse with abscess 3. Mixed infection is the 1st thing to remember with Truparella 4. Truparella & Fusobacterium necrophorum often found together 5. Small gram - rods which are Bacteroides (also anaerobes) 6. Truparella is a facultatitve anaerobe along with Fusobaterium (also facul anaerobe)

What two Actinomyces make branching filaments?

A. viscousus & bovis =both make long branching filaments

What is actually another anaerobe for today? so i guess there is another one even though he said there was just one

Actinomyces bovis

How can you distinguish A. viscousus from Nocardia asteroides?

Both do similar fistulating abscess granulomas in dogs & cats so have to be able to differentiate. So, i think it's the filaments

What causes the pyothorax in cats with Actinomyces viscosus?

Breathing in food -> into lungs causing pneumonia & pyothorax or several different things

How to differentiate the 2?

By microscopy -Actinomyces bovis makes sulfur granules (misnomer because has nothing to do with sulfur & instead phosphate due to degradation of bone-calcium phosphate mixed with proteins)

What is a problem for diagnostic labs growing anaerobic bacteria?

Can take a week to grow something then you have to do ID which also takes time So, mostly this work is done for research purposes but not useful for diagnostic

Diagnostics now adays fro anaerobics are based on:

DNA analysis & using probes =modern tools which a technician can push 3 buttons then get which anaerobic bacteria it is

In pigs when you have urinary tract problems, it's either what or what?

E. coli or Actinobaculum suis (thin rods)

What is the major Fusobacterium in vet med?

Fusobacterium necrophorum

Why is Actinomycetes hard to treat?

If you have granulomatous tissue, it's a pharmacologic issue i.e. for antibiotic to reach inside of pathological formations

Why is Actinobaculum suis unique?

It's an anaerobe! it's the only one that he speaks of due to structure that's an anaerobe

How to detect anaerobes using lab techniques -not yellow

Lab techniques - 1. gram stain 2. gas chromatography -recall lots of these anaerobes product different gases or fatty acids to create a profile of the molecules that are pathopneumonic =tells you what type of anaerobic bacteria you have 3. slow growth (O2-sensitive: thioglycolate media, anaerobic jar or glove box) -need to reculture to make colonies then put in no O2 evironmnet -cheap method: put in environment/little system, water then catalyst on top=produces water from oxygen which keeps the chamger humid -glove box is more complex

Nocardia asteroides: 1. Morphology? 2. Gram + or -?

Long branchiing filaments & gram + -can do acid-fast stain but weaker so need to modify

If you do a giemsa stain of Dermatophilus, what do you see? How can you know you're loking at dermatophilus conco thing?

Long filaments where you have little round bacteria that go out & make zoospores so long filaments are typical =see this & know it's dermatophilus conco...whatever

What does the bone look like in lumpy jaw? What happens?

Lower jaw: deformed -> problems eating

Which other bacteria produces mycolic acid? how do these 2 compare?

Mycobacterium tuberculosis -very similar but structure is is a bit different -> when you stain this bacteria N. asteroides, it's acid fast but much weaker (red like M. tb)

What type of lesions are linked to anerobes

Necrotic, purulent lesions

Is a swab optimal?

No it's obviously suboptimal b/e not a lot of material. -if you take lots of material, send a few mL

Are anaerobes easy to grow? THen what should you do?

No. Then do a gram stain because will help you recognize some of the bacteria

What is important to remember for therapy of Nocardia asteroides?

Nocardia asteroides are penicillin-resistant (in contrast to Actinomyces viscousus)

What are 3 big names that are genera with different examples of species?

Prevotella, Porphyromonas, Bacteroides = all gram -, little rods.

Dog lung in lesion of Actinomyces viscosus what do you histologically?

Pyogranuloma so it looks like a granumola with pus also

Trueperella pyogenes What is the morphology? not in yellow

Rods, don't make filaments

Horse What does a lesion of Streptothricosis look like?

So, bacteria go where the lesion is: Plucked hair tuft with crust (like skin coming out with the hair) =typical of dermatophilosis in dogs & horses i.e. Beagle, crusty lesions on ears & extremities

When you think you have an anaerobic infection, how do you confirm that?

Specimen collection and transport to the lab -consider these bacteria might die long before they reach the lab -whatever material you get, add the syringe too 1. Sealed syringe filled with pus (fluid, biopsy better than swab) 2. Anaerobic transport media -specific for anaerobes 3. Blood culture (3 samples/24 hrs) -not yellow -you can have anaerobic infections that cause bacteremia or septisemia

Actinomycetes make branches like:

Streptococcus except Actinomycetes are rods not cocci

NExt of the Actinomyces & he thinks it's the last one: Dermatophilus congolensis

These things are not in yellow: 1. Obligate parasite of animals 2. Aerobe 3. Parallel filaments (divides in both directions); release of zoospores (chemotactic for CO2); germ tube formation

What does mycolic acid do?

Toxic: 1. Inhibits being killed by macrophages & neutrophils 2. Immunostimulant so causes macrophage to make TNF-alpha 3. Induces macrophages to fuse to multinucleated cells -recall we heard this with Tb

What shape do A. bovis make?

Very strong branching filaments

Does Nocardia asteroides form filaments?

Yes

How does Actinomyces bovis differ from Actinobacillosis?

actinobacillosis attacks soft tissue of the mouth in wooden tongue while actinomyces bovis attacks bone aka hard tissue in oral cavity

What is a problem with vaccines for D. nodusus?

different serotypes for fimbriae so have to have vaccine for right region where they have the problem