Companion Animal Pathology Flashcards
Rapid in-house infectious disease tests (blood)
- SNAP 4Dx Plus (heartworm disease, Lymes disease, Anaplasmosis, and Ehrlichiosis)
- SNAP Lepto
- Angio detect
Rapid in-house infectious disease tests (faeces)
- SNAP Parvo
- SNAP Giardia
ELISA technology
- Detects Ab/antigen
Canine leptospirosis
- Zoonotic
- In water + moist soil
- Reservoir host = small rodents + wildlife -> dogs become incidental host, infected by indirect water contamination w/ urine (on-going urinary shedding = renal carrier status)
- Pathogenic serovars = L. canicola, L. icterohaemorrhagiae; L. bratislava, grippotyphosa, australis
- Entry in mm or broken skin -> leptospiraemia/haematogenous spread -> kidneys, liver, eyes, other organs
- Pyrexia, AKI, bleeding tendencies, icterus (hepatitis)
Canine leptospirosis (Dx)
- Blood results - thrombocytopoenia, azotaemia, inc liver enzymes (ALT/ALP) + hyperbilirubinaemia
- Urine results - isosthenuria, proteinuria, sometimes glucosuria (renal func failure)
- Hx - rat/rural/body of water contact; AKI +/- acute hepatomegaly +/- haemorrhagic diathesis
- Rapid in-house Ab test (vacc Hx) - false +ives
- MAT serology (microscopic agglutination test) - re-test 2 w later if false -ives
- PCR - blood + urine, before AB!! - false -ives
Aspergillosis (dog)
- Localised fungal infection in nose + sinuses - Aspergillus fumigatus
- Cause of chronic nasal discharge (+/- epistaxis) after neoplasia + dental disease in older animals
Aspergillosis (Dx) (dog)
- Culture nasal discharge, pos false +ive/-ive
- Serology - low sensitivity, false +ives rare
- CT - destructive rhinitis
- Rhinoscopy (plaques)
- Histo
Canine parvovirus
- Clinical disease mainly puppies + subclinical pos
- Tropism for rapidly dividing cells in GI tract + BM -> severe enteritis + BM suppression (neutropoenia) -> 2y bacterial infections/sepsis
- V+ + D+ (watery = haemorrhagic)
Canine parvovirus (Dx)
- CS - acute GI disease - enteritis + BM suppression (neutropoenia)
- Snap test any dog w/ haemorrhagic D+ - for subclinical infections
- Exposure Hx
- Vacc status
- Neutropoenia
- Faeces - in-house ELISA antigen (snap test), do PCR if get -ive result
Canine adenovirus
- CAV-1 virus -> infectious canine hepatitis (ICH)
- Causes viraemia - tropism for endothelial cells, epithelial cells + hepatocytes -> systemic disease w/ coagulopathy (endo cells) + hepatopathy (liver dysfunc)
Canine adenovirus (Dx)
- Non-specific CS - pyrexia, lethargy
- Bleeding disorder - DIC, signs of heptopathy/liver failure (V+, D+, neuro (hepatic encephalopathy))
- Urine - inc bilirubin
- Blood - inc ALT/ALP, abnormal coagulation parameters = liver failure
- PCR - on secretions/excretions - blood
Canine distemper virus
- Paramyxoviridae, high mortality
- Airborne aerosols + other spread via excretions/secretions
- Can develop neuro signs, systemic signs depend on immune system
Canine distemper virus (Dx)
- CS - neuro - seizures, ataxia, hypermetria, para/tetraparesis, neck pain; myoclonia (focal twitching of head/limbs generalised) = pathognomic
- CS - systemic - pyrexia, GI, pneumonia (resp), hyperkeratosis nasal planum/foot pads + pustular skin lesions (dermatological changes)
- Travel Hx
- Incomplete vacc Hx / serology
- PCR = main way
Angiostrongylosis (dog)
- Angiostrongylus vasorum = metastrongylid nematode (lungworm)
- Adults live in pul vasculature + RHS of heart
- Dogs infected by L3 larvae after eating infected intermediate hosts (molluscs - snail/slug)
Angiostrongylosis (Dx)
- CS = resp signs, R-sided heart failure (pul hypertension), bleeding tendencies (CNS), hypercalcaemia - PU/PD
- Faeces - modified Baermann flotation (poor sensitivity - intermittent shedding)
- Direct faecal smeal under microscope
- Cyto - tracheal wash/BAL of larvae
- ELISA - angio detect (blood antigen test)
Brucellosis (dog)
- Brucella canis - G -ive bacteria
- Repro signs - zoonotic + emerging (reportable)
- Dog = natural reservoir
- Infected through urine, aborted material, vaginal/seminal secretions -> regional LNs -> bacteraemia (multiple months, chronic infection); other = intervertebral discs, eyes, kidneys
Brucellosis (dog) (Dx)
- CS - repro signs + lymphadenopathy/immune-mediated/chronic bacterial infection, discospondylitis, osteomyelitis, polyarthritis, uveitis, glomerulonephritis
- Bloods - hyperglobulinaemia (+/- hypoalbuminaemia)
- Reactive lymphadenopathy
- (Rapid in-house tests)
- Serology (Ab) = combined test - SAT (serum agglutination test) + iELISA
- PCR + culture
- Ask about travel/import
Toxoplasma (dog + cat)
- Toxoplasma gondii - intracellular coccidian parasite
- More common infection in cat, clinical disease uncommon in cats + dogs, would be due to systemic
- Cat = natural host, dog/human (zoonotic) = intermediate
- Felines = intestinal cycle -> excretion of oocytes in faeces
- All hosts = extra-intestinal cycle (tissue cysts)
- Cause of mainly neuro disease in cats
Toxoplasma (Dx)
- CS (dog) - hepatic, pancreatic, pul, eyes, neuro signs
- PME: organism in affected location - PCR, cyto, histo
- (Serology - IgG (previous exposure) + IgM Ab (active disease))
Giardia (dog)
- Giardia duodenalis - coccidian flagellate protozoan parasite
- Young animals, but GI signs in any age
- Many asymptomatic carriers + intermittent carriers
Giardia (Dx) (dog)
- Small intestinal D+
- Several pooled faecal samples - microscopy, faecal flotation, ELISA antigen, PCR
Toxocara (cat + dog)
- Roundworm, adult nematode in small intestines
- T. canis = dog
- T. leonina = cat + dog
- Common in puppies
Toxocara (Dx) (cat + dog)
- CS in puppies - GI, failure to thrive, pot bellied
- Migrating juvenile nematodes -> hepatic, pul, ocular damage
- Faecal flotation test
Campylobacter (cat + dog)
- G -ive, curved rods
- Zoonotic
- C. jejuni -> D+
Campylobacter (Dx)
- CS - acute haemorrhagic enterocolitis, GI signs
- Fresh faecal analysis - culture (selective medium)
- PCR
Salmonella (dog)
- G-ive, bacillus of enterobacteriaceae family
- Zoonotic
- Intestinal bacteria but can lead to systemic disease (sepsis)
- Reportable disease in dogs
Salmonella (Dx)
- CS - acute haemorrhagic enterocolitis, GI signs, more signs of sepsis
- Fresh faecal analysis - enriched = bacterial culture
- PCR
Protozoa (cat)
- Tritrichomonas
- Giardia
- Toxoplasma gondii
- Babesia (outside UK)
- Leishmania (outside UK)
Fungal (cat)
- Dermatophytosis - most common in UK (ringworm)
Others more prevalent in other countries - Aspergillus
- Cryptococcus
- E. cuniculi
Bacteria (cat)
- Chlamydia felis
- E. coli
- Pasteurella multocida
- Bordetella bronchiseptica
- Campylobacter, Clostridia, Salmonella
- Staphs/strep
- Mycobacteria
- Bartonella spp.
- Haemotrophic mycoplasma
- Respiratory mycoplasmas
Viruses (cat)
- FHV
- FCH
- Corona virus
- FIV
- FeLV
- Panleukopenia
- Rabies (outside UK)
Helminths (cat)
- Lungworm
- Dirofilaria (outside UK)
Cat flu
- Primary agents = FHV (more serious disease); FCV = more common
- Chlamydia felis
- Bordetella bronchiseptica
- Mycoplasma spp
- 2y bacterial infections
- More common in kittens
- Multicat homes
- CS - acute URT disease, cattery stay, mucosal discharge, facial lesions e.g. blepharospasm, conjunctivitis, photophobism, mouth-breathing, drool (oral-ulceration)
- Contact w/ clinical case/asymptomatic carrier common (fomites uncommon)
FHV
- DNA virus
- Single serotype + little isolate variation
- Highly infectious when shedding
- Labile in environment (18 h)
- Transmission - oronasal route
- Inactivated by bleach
- Carrier common - all infected cats, hides in trigeminal n., intermittent shedding
FHV (Dx)
- Chronic clinical signs - skin, resp, chronic nasal + ocular disease (dependent on immune system)
- PCR (doesn’t prove if cause/cross reaction w/ vaccinal strains)
- POCUS
FCV (Feline Calici Virus)
- RNA virus
- Single serotype + variation between isolates, mutates more
- Fairly labile = 7 - 10 d
- Inactivated by bleach
- Persistent shedding
- Role in acute + chronic disease - resp, oral lesions, chronic gingivostomatitis, limping syndromes, fatal systemic disease
FCV (Dx)
- CS
- PCR (negative doesn’t exclude)
FHV - chronic disease
- Corneal diseases
- Herpes dermatitis
- Chronic rhinosinusitis
- Polyps
- Laryngeal disease
- Nasopharyngeal stenosis
Feline panleukopoenia
- Infectious in environment for months
- Can titre test (for vacc - provides lasting immunity, years)
Feline panleukopoenia (Dx)
- Titre test
- POCUS
Feline coronavirus (FCoV)
- Ubiquitous, 2 serotypes
- Highly contagious
- RNA virus
- High mutation rate - within individual cat
- Can cause FIP, but doesn’t in majority of cats
- Systemic spread within macrophages
- Mainly intestinal epithelial replication
Feline infectious peritonitis (FIP)
- Develops when FCoV mutates in individual cat -> able to leave gut + replicate within macrophages
- Systemic spread within macrophages within blood vessel walls and sustainable replication -> vasculitis/serositis + effusions
- Perivascular granulomas - liver, kidneys, brain, eyes
- Risks - stress, genetics, cat origin, young cat (< 6 m, 2nd peak = 10 y)
FECV
- Mainly intestinal epithelial replication
FIP (Dx)
- CS (varied, systemic disease) - neuro, ocular, jaundice, effusion - yellow, ascites, swollen LNs, keratic precipitates
- Bloods (in order of percentage of cases) - A:G < 0.4, hyperglobulinaemia, anaemia, hyperbilirubinaemia, neutrophilia, lymphopoenia
- Bloods can normal in some neuro cases
- POCUS
FCoV (Dx)
- Serology - only indicates exposure (does not = FIP), can stay +ive for many months
- Interpret w/ CS, other results + home environment
- Take fluid sample
- POCUS
Clostridiosis
- C. perfringens enterotoxin A gene PCR
- Small + large bowel D+
Clostridiosis (Dx) (Cat)
- Faecal PCR
- ELISA - toxin detection