Salmonella is a gram ____ bacterium, that is found in ________, and it easily transmitted between _______ and _______.
Gram negative
Found in the environment
Transmitted between humans and animals
*can get it from contaminated food, water, and undercooked food
What animals will show clinical signs of salmonellosis?
Mostly seen in puppies or young animals vs adults
What are the clinical signs of salmonellosis?
(none –> severe gastroenteritis)
Vomiting and dhr
Dhr: watery to mucoid to hematochezia - can result in hypovolemia and septic shock
+/- neutropenia
What diagnostic tests are used to diagnosis salmonellosis?
Fecal culture (plus clinical signs/history)
*a positive isolation from feces does not mean salmonellosis and negative culture results do not rule out infection
What is the treatment for salmonellosis?
Antibiotics: Chloramphenicol, SMZ, Amoxicillin, Ampicillin
+/- intravenous fluids
T/F: All positive cases of salmonellosis should be treated with antibiotics?
FALSE
if patients have minimal signs or asymptomatic - no treatment is required
T/F: Many dogs are asymptomatic carriers of campylobacter organisms
TRUE
Cats too
Campylobacter infections will cause large or small bowel diarrhea? What clinical signs are associated with infection?
Large bowel diarrhea: mucus, tenesmus, hematochezia, increased frequency, flatulence
other signs - pyrexia and possible leukocytosis
How is campylobacter diagnosed?
- microscopic evaluation of feces - gull winged shape bacteria
- Culture
- PCR
What is the treatment for campylobacter infections?
**efficacy of ABs is unknown
Erythromycin, chloramphenicol, cephalosporins, enrofloxacin can be used
treatment is difficult
How does helicobacter survive low pH of the stomach?
Produces high levels of urease which will make the pH more basic so the bacteria can survive
What clinical signs may be seen with a helicobacter infection?
+/- chronic gastritis - chronic vomiting, weight loss, emaciation or diarrhea. Blood may be noted in the vomit and diarrhea
How are helicobacter infections diagnosed?
Histology: gastric biopsies, Culture - very difficult, PCR on gastric samples
What is the therapy used for helicobacter infections?
Two antibiotics + anti-acid
Amoxi + metro + omeprazole
amoxi + metro + famotidine
difficult to treat
What animals are resistant to brucellosis infections?
Cats!
How do animals get infected with brucella?
Transmitted through aborted fetal material, semen, urine, milk, possible orally or conjuntivally
Penetrates the MM and enters the lymphoreticular system
Why is brucella difficult to treat?
It will persist intracellularly so it can hide from the immune system
*highest concentrations in vaginal discharge and semen
What clinical signs are associated with brucellosis?
Bacteraemia 1-4 weeks (can be longer)
- some dogs may be asymptomatic
- generalized lymphadenopathy, transient fevers, seizures
- *more of a problem in intact males - enlarged scrotom, epididymitis, infertility, testicular atrophy
- females - abortion, stillborns, infertility
*discospondylitis, chorioretinitis, optic neuritis, anterior uveitis
What diagnostics can be performed to diagnosis brucellosis?
Hematology - leukocytosis
Biochem - hyperglobulinemia with hypoalbunemia
CSF - neutrophilic pleocytosis with increased protein levels
**Rapid slide agglutination test (RSAT)
**Tube agglutination test (TAT) - titers over 200 indicate an active infection (titers 50-100 suspect an infection)
Elisa, PCR, Bacterial culture
Serology for brucellosis is usually negative for ______ post infection
2-4 weeks post infection
titers stay positive for up to 3 years
What is the treatment protocol for brucellosis?
Intact animals should be spayed/neutered
Doxy plus Streptomycin
Combos: aminoglycosides, doxy, quinolones
Usually at least 4 weeks of therapy
Retest after tx: 6 to 9 months post therapy (TAT less than 100 and ACID should become negative)
_____ and ____ species are gram positive, branching bacteria. Often sulfur granules will be noted in these infections
Actinomyces and Nocardia
What kind of infections are associated with Actinomyces?
anaerobic infections, FB migrations, pyothorax, peritonitis, bite wounds. Often draining tracks will be noted and yellow granules
What infections are nocardia spps associated with?
Wounds and pyothorax
How are actinomyces and nocardia infections diagnoses?
Cytology and culture
***always tell the lab to hold onto the culture for 10 days, as these are slow growing
What is the tx protocol for actinomyces and nocardia infections?
surgical drainage and debridement
Actinomyces - penicillins: tx for 4 weeks post clinical resolution
Nocardia: SMZ (trimethoprim sulphonamides) x 6 weeks
What pathogen causes lyme disease?
Borrelia burgdorferi
What is the vector of borrelia burgdorferi?
Ixodes spp
Deer tick: northeast, mid western, and south east
Western black legged tick: pacific coast
When do hosts become infected with B. burgdorferi?
48-50 hours post attachement once the tick engorges
Temp. and pH (increase to 37C and lower pH) change from engorgement will down regulate outer surface proteins A and B, and outer surface protein C will get passed into the salivary glands of the tick to be passed into the host
Where does B. burgdorferi go in the body?
Likes to hide in the brain and joints - evades the immune system even though it is extracellular
What percentage of lyme positive dogs will have clinical signs?
What are the clinical signs noted?
only 5 - 10%
- *pyrexia, lymphadenopathy, *lameness - polyarthritis, renal dz (protein loosing glomerulopathy), meningitis, myocarditis
How long does it typically take clinical signs of lyme dz to develop after being bitten by a tick?
about 2-5 months but exact incubation period is unknown
The most common clinical sign noted in lyme positive dogs is…?
Non-erosive polyarthritis
- the surface of the joint will appear normal, but there is inflammation noted in the joint/fluid
- increased neutrophils, proteins, B. burgdorferi organisms may be present
what breeds of dog are over represented for clinical presentation of Lyme dz?
Goldens and labs
What clinical signs are associated specifically with protein loosing glomerulopathy from lyme disease?
Vomiting, dhr, PU/PD, peripheral edema, ascites
*lab work: non regen. anemia, stress leuk, thrombocytopenia, azotemia, low alb, hyperphosphatemia, hypercholesterolemia
UA - proteinuria, hematuria, glucosuria, bilirubinurea
T/F: there is a pathognomonic test for B. burgdorferi
FALSE
When using serology to test for lyme dz, what are you testing for?
screening for antibodies against B. burgdorferi
*this indicates exposure - but does not prove clinical illness
**testing for antibodies to outer surface protein C6 is more sensitive and specific (SNAP) but it does not always correlate with clinical illness. *can differentiate between vaccinated animals and infected animals
*paired serum titers are better to dx active dz
What animals are treated for lyme disease?
- the dog that tests positive (C6 SNAP) and has clinical signs
- Any lyme positive dog that has proteinuria and elevated urine UPC
***tx for positive animals not displaying clinical signs is controversial
What is the tx for lyme dz?
***Doxy (drug of choice) 5mg/kg BID x 30d
amoxicillin, azithromycin, ceftriaxone
What methods of prevention are used for lyme dz?
Tick prevention!! on the the animal and the environment
Vaccination - used in areas where the dz is common, for outdoor hunting dogs etc
*2 vax are given 2-4 weeks apart, then annual booster
T/F: Dogs and cats are a source for humans to get lyme dz?
False - they do not excrete infectious organisms in their bodily fluids
but they can bring ticks into the house
T/F: Leptospirosis is commonly seen in cats
False
rarely seen in cats
What are some of the most common lepto spps seen in canine infections?
L. Canicola, L icterohaemorrhagia
L. grippotyphosa - midwest/northeast US/Canada
Washingtonstate serovars - Autumnalis, Bratislava, Pomona
What is the route of transmission of lepto?
Direct: urine, venereal and placental transfer, bite wounds, or ingestion of infected tissue
Indirect - Contaminated water sources, soil, and food (MOST COMMON)
What is the ideal environmental conditions for lepto to survive for several months?
Slow moving warm water
Soil pH neutral or slightly alkaline
**Urine with higher pH
Ambient temp (0-25C)
Lepto organisms do not like freezing, dehydration, or UV light
What is the incubation period of lepto?
3-7 days
Once the organism enter the blood they will multiply rapidly
What locations in the body do lepto organisms like to spread?
Kidney spleen CNS Eyes Genital tract
**attach to endothelial cells –> causing edema and vasculitis, acute endothelial injury and hemorrhage
When a patient is in the carrier state of leptospirosis, where are the organisms in the body?
attached to the rental tubular epithelial cells - can shed in urine for months
What dogs are more commonly infected with lepto?
Younger dogs
What clinical signs will be noted in a patient with leptospirosis?
Fever - bacteremia, tachypnea, rapid irregular pulse, vascular collapse, widespread petchiae, hematemesis, hematochesia, melena, epistaxis, icterus, intestinal intussusception, oliguria/anuria, anorexia, vomiting
What changes will be noted on a CBC/Chem/UA of a patient with leptospirosis?
CBC-decreased PLT, neutropenia, decreased HCT
Chem - hepatic/renal dz
UA - SG less than 1.029, proteinuria, glucosuria, bilirubinuria, pyuria, hematuria, granular casts, bilirubin crystals
What (non-blood work) diagnostics can be performed to help diagnose lepto?
Thoracic radiographs - nodular opacities associated with vasculitis and hemorrhage
abdominal US - enlarged kidneys, medullary band increased echogenicity, pyelectasia, increased cortical echogenicity, mild perirenal fluid accumulation
Renal biopsy
T/F: Bacterial cultures are a good test to run when suspicious of a leptospirosis
FALSE
this organism does not grow well - needs a special lab and a long turn around time
What serology test can be used to diagnosis leptospirosis? How does it work?
MAT - microscopic agglutination test
MAT greater than 1:3200 = dz is present (unless recently vaccinated)
MAT greater than 1:800 = may indicate active dz
*if peracute dz, serum titer may not be elevated, therefore repeat sample 2 to 4 weeks later to check for increase
PCR can detect the lepto organism in the ______, within the _____ week of infection
blood, within the first week of infection
- it is still always best to send a blood and urine sample to ensure you find the organism
- use in combination with serology
what is the treatment protocol for leptospirosis?
Supportive care - (depends on severity) patient may need a central line, U-cath to monitor urine output, replacement fluids, anti emetics and GI protectants, plasma or whole blood transfusion
Antibiotics: Doxy for 2 weeks in patients withOUT hepatic or renal damage
patients with renal/hepatic damage can be put on penicillin or ampicillin and treated later on with doxycycline
What methods of prevention are used for leptospirosis?
Vaccines - but these are not 100% effective due to the many, varying serovars
need to know what serovars are commonly found in your geographic area and choose the vax wisely
- immunity is not long acting
- vax does not prevent carrier state