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205 Cards in this Set
- Front
- Back
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Seizures in dogs - 8 differentials
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Idiopathic epilepsy
Brain neoplasia (astrocytoma, meningioma) Insulinoma Hepatic encephalopathy Hypocalcaemia (late preg) Granulomatous meningoencephalopathy Toxins (Metaldehyde, Slug bait, Marijuana, choc, 1080, lead) Tremorgenic mycotoxins |
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7 differentials for fading in 5yo sheep
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Parasites
Intestinal Adenocarcinoma Teeth Johnes Lameness Pneumonia Facial eczema (Liver fluke, malnutrition, trace elements) |
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Where do toxins affect the kidneys?
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All affect the proximal tubules EXCEPT NSAIDS - cause vasoconstriction of renal arterioles
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3 stages of Ethylene Glycol Toxicity
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1. Drunken behaviour - tx w ethanol
2. Oxalate crystals form in blood, bind calcium - paresis, paralysis, weakness 3. Ca is filtered out of blood in kidneys - sharp crystals form in proximal tubules - ARF |
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Why is FIP a misnomer?
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Not infectious and not a peritonitis
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Morphological Description contents
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EDDEAMO
Extent duration distribution exudate anatomical modifier organ |
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What is fading Elk syndrome?
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Type II ostertagiosis
(L4 inhibited in winter, all emerge at same time in spring) |
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What does "itis" infer?
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Inflammatory
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What does "osis" infer?
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Chronic degeneration without inflammation
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What does "opathy" infer?
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Acute degeneration without inflammation
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What does Se deficiency cause in
1. lambs? 2. pigs? |
1. Lambs -White muscle disease
2. Pigs - Vasculopathy leading to mulberry heart disease or hepatosis dietetica |
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9 causes of sudden death in piglets
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Iron overload
Trauma Hypothermia Oedema disease (E.cole - Shigella-like toxin - vasculopathy) Starvation Dystocia E.coli scours Intrauterine infections (PRRS or parvo - SMEDI) Congenital malformations |
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Common cause of vasculitis in:
1. Cows 2. Dogs 3. Cats 4. Pigs |
1. Cows - MCF
2. Dogs - Uraemia 3. Cats - FIP 4. Pigs - Erysipelothrix rhusopathiae (diamond skin dz) |
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What does herpes do to:
1. Puppies 2. Pigs |
1. Puppies - multiple deaths. See red spots in kidneys. Prevention - keep warm herpes doesnt like T >38 degrees
2. Pigs - Aujesky's disease |
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3 things to check for in a newborn lamb post mortem
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1. Did it breathe? lung expansion
2. Did it walk? Slippers 3. Did it feed? Milk in GIT |
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How do we diagnose portosystemic shunt
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Look for ammonium biurate crystals in urine. Failure to thrive, hepatic encephalopathy.
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8 congenital heart malformations
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Patent ductus arteriosus
Ventricular septal defect Atrial septal defect Persistent right aortic arch Subaortic stenosis Pulmonic stenosis Juxtaposition of major vessel Tetralogy of Fallot |
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10 common causes of death in birds
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1. Psittacosis
2. Air sacculitis (aspergillus) 3. Tuberculosis (liver) 4. Egg peritonitis 5. Egg binding 6. Marek's disease 7. Parasites (coccidia) 8. Bacterial respiratory infections 9. Crop impactions 10. Malaria |
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4 common causes of death in chickens
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Egg peritonitis
Egg binding Marek's disease Parasites - coccidia |
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Most common sole clinical sign of FIP
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Neuro signs (25% will only show neuro signs)
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9 differentials for neuro dz in a 4yo cat
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1. Chronic ear infxn (otodectes, nasopharyngeal polyps)
2. Tumour 3. Toxoplasmosis (Neural tissue, lung tissue) 4. Meningitis (rare) 5. Trauma 6. FIP 7. Cryptococcus 8. Toxicity 9. Ethylene Glycol (ARF - hypoCa, azotaemia) |
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What is hog cholera?
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Cerebellar hypoplasia in pigs
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4 Causes of abortions in sheep
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Campylobacter
Toxoplasmosis Salmonella Hairy Shaker (pestivirus) - cerebellar hypoplasia |
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Signs of campy abortion in sheep
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Target lesions on liver, seagulls in stomach aspirate
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Signs of toxo abortion on sheep
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Strawberry cotyledons with mineralisation
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5 causes of abortion in cows
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1. Neopspora
2. Lepto 3. Listeria 4. BVD 5. Fungal |
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PM signs of Neospora abortion
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Nothing seen on gross exam. Take calf brain for encephalitis testing
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PM signs of lepto abortion
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Difficult to diagnose - see low grade placentitis. Same as Listeria
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PM signs of Listeria abortion
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Difficult to diagnose - see low grade placentitis. Same as Lepto
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Signs of BVD
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Stage of gestation determines whether EED, PI, Cerebellar hypoplasia, abortion or immunocompetent and immune. Cerebellar hypoplasia - if calf viable see intention tremor, hypermetric gait.
No placentitis seen. |
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Signs of fungal abortion
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Fungal plaques on calf (looks like ringworm), placentitis - massive necrosis and oedema so opaque placenta.
Mortierella wolfii - North Island Aspergillus - South Island If Mortierella wolfii, 25% of cows get pneumonia after abortion. |
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4 classifications of pneumonia
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Embolic
Bronchopneumonia Interstitial Granulomatous |
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Cause of Embolic pneumonia in smallies
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Neoplasia - eg osteosarcoma, mammary neoplasia, ruptured haemangiosarcoma in right atrium
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3 Causes of Embolic pneumonia in largies
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Mortierella wolfii
Endocarditis Caudal vena cava syndrome (pulmonic embolic aneurism) |
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Pathogenesis of PEA (Pulmonic Embolic Aneurism)
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=caudal vena cava syndrome.
Acidosis (grain) - bacterial infection of rumen wall - bacteria enter bloodstream - liver abscesses - rupture into caudal vena cava - thromboemboli enter right heart, lungs, and may cause rupture of pulmonary artery |
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What is pleuropneumonia?
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= severe form of bronchopneumonia. Damaged blood vessels allow fibrin to leak out, get fibrin in pleural cavity
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Distribution of bronchopneumonia
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cranioventral
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Causes of bronchopneumonia in
cows |
Aspiration pneumonia, shipping fever (-pleuro), enzootic pneumonia, calf pneumonia
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Bacterial causes of pleuropneumonia in cows, sheep, pigs
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Cows - Mannheimia haemolytica
Sheep - Mannheimia haemolytica, Pasteurella multocida Pig - Actinobacillus |
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What kind of pneumonia is it common to see rib imprints in lungs and why?
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Interstitial, lungs overexpand.
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Causes of interstitial pneumonia in
1. Dogs (2) 2. Cats (1) 3. Pigs (1) |
Dogs - Paraquat toxicity, Distemper
Cats - FIP Pigs - PMWS |
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Pathogenesis of interstitial pneumonia in paraquat toxicity
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Clara cells in lungs try to destroy toxins - lots of free radicals produced - type I pneumocytes destroyed and basement membrane sometimes destroyed. Prognosis depends on whether BM destroyed or not.
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Describe a granulomatous lung lesion
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Fibrous round outside, soft centre
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Causes of granulomatous pneumonia
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Rhodococcus in horses (ubiquitous), TB, Cryptococcus
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Where do FIP lesions occur?
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Anywhere there are blood vessels
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How does FIP occur?
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All cats have coronavirus in intestine. FIP occurs if it mutates - travels in blood monocytes - get Ab-Ag complexes, cause vasculitis when they get stuck in vessel walls. Infarctions occur esp kidney and liver - pale spots.
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Why are there two different forms of FIP?
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Effusive (wet) or non-effusive (dry). Depends on severity - severe - lots of fibrin leaks out of vessels. Less severe - small amount leaks out, macrophages mop it up.
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Most common cause of ARF in cats? How does ARF kill?
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Bladder stones. Buildup of K in blood - heart stops.
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How do we lower K in blood?
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Fluids w glucose added - body uses K to get glucose into cells. Also give insulin.
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3 causes of cushings and their incidence
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80% Pituitary tumour
15% Adrenal tumour 5% Iatrogenic |
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How do Addisons patients die?
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No adrenal cortex - can't produce glucocorticoids or mineralocorticoids - increased K:Na ratio - die
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What causes SCC and where (in general) do they occur?
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UV light. Areas with no pigment and no hair
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What is osteopetrosis and who usually gets it?
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Faulty osteoclasts - no marrow cavity. Angus cattle. Born alive, die soon after.
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Where do you see SCC in
1. Cats (4) 2. Dogs (1) 3. Horses (3) |
Cats - ears, eyelids, nose, base of tongue
Dogs - ventrum Horses - eyelids, vulva, penis/prepuce |
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What is a perineal melanoma and who gets them?
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Grey horses. Melanin doesn't attach to hairs (hence grey) - accumulates in dermis - turns into a melanoma. Euth when it erodes or gets big. Rarely met.
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Most common and 2nd most common skin tumour in dogs?
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Histiocytoma, lipoma
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Most common malignant skin tumour in dogs?
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Mast cell tumour
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Cyto characteristics of histiocytoma
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Big round cells with very PALE cytoplasm
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How do you get rid of a histiocytoma?
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FNA - regresses 2 weeks
If not, regresses 4 weeks |
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How do we diagnose a SCC?
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Impression smear (or scraping if on cat tongue to ddx from Eo granuloma). Look for NUCLEATED keratinised squamous cells - disorganisation of maturation
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What causes Eo granuloma on cats tongues and what do you have to Ddx from?
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Hypersensitivities, SCC
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Where do cats get Eo plaques?
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Ventrum
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What dermatitis is commonly caused in cats by fleas?
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Miliary dermatitis
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Raised nodule on cats nose - primary differential?
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Mosquito bite allergy
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3 Ddx for necrosis in dog brain
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Nasal cavityFungi (aspergillus)
Adenocarcinoma of nasal cavity Sinusitus |
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Differentials for bilateral and unilateral epistaxis in dog?
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Bilateral - clotting disorder
Unilateral - nasal adenocarcinoma, aspergillus |
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How to diff between nasal adenocarcinoma and aspergillus in dogs?
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Biopsy (look the same on rads)
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What causes blackleg?
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Cl. chauvoei - Trauma - germinate - vasoconstrictive toxin, decreases O2 to site and prevents Neuts from getting to site
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Fibrin clot in pericardium - what caused it?
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Pathognominic for Clostridial enterotoxaemia. Kidney damage occurs post mortem, don't mention in exam!
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What causes black disease?
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Cl. novyi
Liver fluke allows spores to germinate |
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3 most common causes of death in old cat
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Hyperthyroidism
Intestinal Lymphosarcoma Renal failure |
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2 PM findings to confirm renal failure in cat?
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1. Calcification occurs in the three places in the body that secrete acid, due to decreased excretion of phosphorus. Lung, kidney and stomach.
2. All four parathyroid glands enlarged due to Ca being mobilised |
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What do we see with hyperthyroidism?
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Hypertension causes HCM, and detached retinas sometimes. Increased vent, thickness, dilated atria, jet lesions (AV regurg), atrial thrombi, saddle embolism
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Site of RSCHF oedema in:
1. dogs 2. cows 3. cats |
Dogs - ascites
Cows - SQ oedema - bottlejaw, brisket Cats - hydrothorax |
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What causes nutmeg liver?
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Chronic passive congestion (RSCHF)
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Two things that can cause damage to kidney glomerulus in cats?
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Amyloidosis, immune-med glomerulonephritis
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3 causes of chylothorax in cats?
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Idiopathic, ruptured thoracic duct, CHF
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Diagnosis of chylothorax in cats?
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White fluid in thorax - send to lab to test for triglycerides or leave 24hrs and fat will settle to top.
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Samples to take in bovine abortion case
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Placenta - esp cotyledons (if thick, membrane too)
Foetal abomasal fluid (culture, indicative of amniotic fluid) Brain (neospora, toxo) Liver Spleen, heart blood if BVD suspected (serology) Lung (culture) |
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3 causes of corneal ulcers in cats
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Scratch
Herpes (weird linear ulcers are deep, or shallower punctate ulcers) Lagophthalmos |
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Where in a blood smear do you look for platelet clumping?
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Feathered edge (also heartworm dirofilaria)
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Non-lesion causing reddened parts of intestine in ruminants?
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Splanchnic pooling
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Placental signs of fungal abortion
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Intercotyledonary membrane thickened, opaque, necrotic plaques. Cotyledons swollen dt fungal hyphae invading blood vessels, red ring around them.
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What is phthisis bulbi?
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Granulomatous rxn causing eye bulb to shrink, due to penetrating wound. Chance of getting carcinoma so remove eye.
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What is Vitiligo?
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Cease in prodn of melanin - change colour. Young rottweilers
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What is sebaceous adenitis?
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Body creates immune response against sebaceous glands. Alopecia, non-pruritic. Standard poodles.
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Adv and disadv of skin biopsy
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Disadv - expensive
Adv - Prolonged ineffective Ab tx just as expensive and no diagnosis. |
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What is impetigo?
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Superficial pustular dermatitis, occurs in young animals during puberty bc immunocompromised. Excellent response to tx.
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What is Hepatic Cutaneous Syndrome?
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Liver doesn't produce amino acids properly - aa imbalance- get lesions on hard pads of feet.
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What causes discoid lupus and what does it look like?
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UV light - inflammation. Immune mediated response.
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Ddx for discoid lupus in Akitas
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Uveodermatologic disease. Affects any pigmented skin. Can go blind quickly so diff from discoid lupus asap.
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What is Pemphigus foliaceous?
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Autoimmune disease - Abs against intercellular tight junctions. foliaceous, vulgaris etc refer to how deep lesions go. Diagnose biopsy, Tx high steroids
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What is feline leprosy?
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Caused by mouse bites - mycobacterium lepraemurium. Take biopsy bc difficult to culture.
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Distribution of FAD and why?
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Dorsum, because cat/dog can't eat them there. Christmas tree pattern.
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Common cause of recurrent ear infxns
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Atopy
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Common sites for Sarcoptes
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Ears, elbows.
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Why don't we biopsy itchy dogs?
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All the disease look identical histologically. All due to self trauma.
Atopy, Food allergy, Contact dermatitis, sarcoptes, malassezia, FAD |
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Most common breed affected by skin malassezia and what is it called in them?
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Westies, epidermal dysplasia
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What underlying dz do we need to r/o in Malassezia?
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Seborrhoea
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What is Seborrhoea?
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Increase in epidermal cell turnover. Cells immature when they reach surface - not dry or fully keratinised - wet moist layer of cells on surface that don;t flake off so stay on skin too long, ideal conditions for yeast etc to colonise.
Can be greasy or dry. Special shampoos get rid of the extra layer or epidermal cells on top. |
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MCT is the "?th" most common skin tumour in dogs
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6th. There are benign things that happen more commonly.
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What is a histiocyte and how does it cause the presentation of histiocytoma?
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Resident tissue macrophage. Attacks epidermis so ulcerates. FNA causes inflammation - allows lymphocytes to tell the histiocytes that the skin is ik hence they resolve.
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3 presentations of Demodex
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Juvenile localised (caused by pubery, self resolves)
Juvenile generalised (tx for 2ndy bact infxn) Adult immunosuppression (resolves when underlying dz is resolved) |
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Do we biopsy ringworm?
sarcoptes? hypothyroidism? |
No, No (best diag is response to tx), no (blood tests better diag)
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Mechanism of non-thyroid alopecia - causing endocrinopathies?
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Hair follices go from anagen to telogen - no new hairs - alopecia. Biopsy.
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4 categories of non-thyroid endocrinopathies causing alopecia?
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Sex hormone, Growth hormone, Cushings (take bloods), Cyclical (boxers and bulldogs, dt move from one hemisphere to other)
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What bacteria cause bacterial skin infxns and what causes it?
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Staph intermedius or other commensals. Decreased immunological responses.
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Which Ab do we use to tx Staph intermedius
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The cheapest - not resistant to anything
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Where do we take skin biopsies from in a) inflammatory and b) non-inflammatory skin lesions?
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Inflamm - edge of lesion, more recent lesions. Non-inflamm (only the 4 non-thyroid endocrinopathies) - take the most affected part.
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What is Puppy strangles?
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Sterile granulomatous dermatitis and lymphadenopathy. Misnomer bc not caused by bacteria. Histo - looks like bacterial infxn.
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Signs of sertoli cell tumour and where does it develop?
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Increased oestrogen - hair loss, gynaecomastia, bone marrow suppression. Almost always in undescended testicles.
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Three types of testicular tumours?
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Sertoli cell, seminoma, leydig (interstitial) cell
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Which two testicular tumours occur in descended testes?
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Seminoma and leydig/ Both behave exactly the same as each other.
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What is SLE?
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Systemic Lupus Erythematosus. Abs produced against cell nucleus throughout body. Lots Ag-Ab complexes, deposit in vessels - arthritis, renal disease (see protein in urine).
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How would you differentiate DL from SLE for a tip of nose lesion?
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Check mouth or other surrounding areas. If only one spot, likely discoid lupus.
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What is a rodent ulcer in a cat?
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Eo granuloma in mouth. Caused by hypersensitivity.
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4 presentations of hypersensitivity in cats?
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Eo granuloma (breakdown of collagen)
Miliary dermatitis Eo plaques (skin esp ventrum, med hindlimbs. Pruritic, raised, ulcerative, LNs enlarged). Chronic trauma |
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What may be mistaken for bladder stones in rabbits and horses and why does it occur?
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Buildup of calcium carbonate crystals in bladder, toothpaste-like sludge. Bc they clear Ca in urine. If bladder doesn't empty properly eg spinal prob, blockage, get buildup. Thick discharge around cloaca.
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Whay don't SCCs exfoliate very well? What is the consequence for diagnostics?
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As well as epithelial, also get lots of fibrous tissue in SCCs. So do scraping, not impression smear.
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What would cyto of a SCC in a LN look like?
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Epith. cells in LN (shouldn't be there)
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Two forms of lymphoid tumours in birds?
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Marek's disease (young), Avian leukosis
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What does a granulomatous reaction look like cytologically?
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Activated macrophages, multinucleate giant cells, sometimes lymphocytes, plasma cells
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What bacteria caused pyelonephritis in cattle?
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Arcanobacterium pyogenes
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What is pseudonecrosis of the liver?
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PM change, if dead for a few days - looks like liver necrosis
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How do we differentiate pentobarb precipitation from metastatic calcification?
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Does it scrape off? Met Ca is IN muscle so won't scrape off.
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What happens to GGT with liver damage?
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Spikes above 800 then tapers
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What GGT level would you expect in
-acute liver damage -chronic liver damage |
Acute - high for 2 weeks
Chronic - normal because has tapered |
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What does subacute sporidesmin tox look like?
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Pale fibrotic liver, not quite at boxing glove stage.
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What are dark nodules in chronic liver damage?
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hepatocytes trying to regenerate
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Boxing glove liver - what level of the following would you expect and why?
a) GGT b) albumin c) globulin |
GGT - normal (has tapered if chronic)
Albumin - low bc going into liver failure, decreased prodn Globulins - high to normal because compensatory increased prodn. |
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What pathognomonic histo lesions do we see from sporidesmin toxicity in liver and why?
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See artery and vein but no patent bile duct to complete the triad, see purply cells and fibrosis instead. Because spor. tox targets the intrahepatic bile duct.
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Lamb livers - where would you expect to see burrowing
a) Cysticercus tenuicollis b) fasciola hepatica |
a) Cysticercus tenuicloois - subcapsular
b) fasciola - anywhere, burrows right thru liver |
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3 Ddx for pale cat liver
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Fatty liver, lymphoma, mast cell tumour
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Fatty liver in cat - what is likely diagnosis and how would you confirm? What if the cat was alive?
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Diabetes - check urine for ketones and glucose. If alive, check blood fructosamine. Stressed cats - high glucose.
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How do we diff btwn the 2 main ddx for a severe lesion on tongue of cat?
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Scrape it - Eo = Eo granuloma, squames/epith cell rafts = SCC
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What does a Sertoli cell tumour look like?
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White and HARD. Lots of dense fibrous connective tissue. Small.
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What does a Leydig (interstitial) cell tumour look like?
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Discrete yellow and red, bulge from cut surface. On FNA see capillaries with tumour cells hanging off.
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What is the significance of a leydig tumour?
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Incidental finding.
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What does a Seminoma look like?
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Cream coloured mass, bulges from cut surface, space occupying lesion contained within the tunic. Look like lymphoid tumours. Good prognosis.
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6 Ddx for cow with lumps in skin
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Papilloma
Cutaneous lymphosarcoma Anzootic bovine leukosis (5+yrs) Hives/insect bites Melanoma Mast cell tumours |
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Enzootic Bovine Leukosis (EBL) signalment and 3 most common sites of lesions
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cow 5+ years old. Heart (RA), abomasal mucosa, uterus. Also can see exophthalmos.
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Two types of Bovine Lymphoma
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1. Sporadic (juvenile, cutaneous or thymic)
2. EBL (>5yrs old) |
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Cattle with plaques and alopecia on face, bum - likely diag?
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Ringworm
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Cat liver multifocal white lesions bulging above capsule?
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Must be neoplastic if bulging above liver surface. Lymphoma.
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Why does FIP cause the typical lesions on cat kidneys?
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White lumps on capsule following blood vessels - bc FIP causes phlebitis. Can be diff to ddx from lymphoma
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What causes papular stomatitis in calves and how does it present?
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Parapoxvirus, small round lesions in mouth. = orf in sheep
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Likley diagnosis for yearling steer, irregular erosions on tongue, hard palate, oesophagus, covered by fibrinonecrotic membrane, haemorrhagic.
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Mucosal disease.
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5 questions to ask yourself when examinig cyto slide
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1. Are there cells present?
2. Are the cells well stained? 3. Are the cells inflammatory or non-inflammatory? 4. Which cell types are present? (epith, mesen, round) 5. Benign or malignant? |
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7 signs of malignancy (need 3 to confirm)
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Anisocytosis
Anisokaryosis Multiple nuclei Multiple nucleoli Mitosis In wrong place Anisonucleoliosis |
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5 kinds of inflammatory cells seen in cytology
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Mast cells
Neutrophils Eosinophils Macrophages Lymphocytes |
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When do you use redirection instead of suction for FNA?
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Fragile cells eg FNA lymph nodes
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3 adv of skin biopsy
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1. Suggests diagnosis in wide range of diseases (bacteria, fungi, parasites, autoimmune, hypersens, endocrine, neoplasia - but not always best way to diag some of these dzz)
2. Easy to do 3. Only way to diagnose some diseases |
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Disadv of skin biopsy
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1. Expensive
2. Has limits - confirms endocrine but not which one, can't tell which hypersensitivity, not diagnostic where there are lots of 2ndy changes |
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6 indications for skin biopsy
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1. Dz not responding to clinically appropriate tx
2. Suspect skin lesions are due to internal disease 3. A ddx is life threatening 4. Tx is expensive or dangerous 5. If its the only way to diagnose (eg T cell lymphosarcoma) 6. When infectious agents that are difficult to culture are suspected (eg rhodococcus, mycobacterium) |
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2 indications to not do skin biopsy
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1. Unlikely to get additional info
2. If there are better diagnostic tests |
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7 things to include in hx to send to lab with skin biopsies
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Breed
Age Sex Distribution of lesions Prev tx and results of tx Bloods Ddx list |
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3 sites of effusions
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Pleural
Pericardial Peritoneal |
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3 classifications of effusions
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Transudate (early heart failure, hypoalbuminaemia)
Modified transudate (haemorrhagic, chylous) Exudate (Septic, inflamm, or neoplasia - because lots of cells exfoliated) Cell count, TP increase each level Spin down for cyto |
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Cyto of effusions - what does granular purple stuff in background mean?
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High protein content
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5 things to consider when looking at effusion cyto
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Background staining - high protein content?
Cell numbers and types Inflammatory or not? Inflamm - any organisms present? or could be inflamm asst w tumour Non-inflamm - any evidence of malignancy? |
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What tumours can cause septic peritonitis?
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Tumours of the GIT
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Which LNs are the best to FNA to assess generalised lymphadenopathy and why?
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Prescapular and popliteal. Because submandibular and mesenteric are more reactive due to constant exposure to Ags
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Why do we aspirate LNs?
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Differentiate btn hyperplasia (reactive LN) or neoplasia. Or to check for mets to LNs.
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What is the problem with aspirating very large LNs?
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Necrotic centre - non-diagnostic if aspirate centre
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Normal LN - cellular makeup
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85-90% small lymphocytes
Rest are med-large lymphocytes, plasma cells, and sometimes No, Eo, mast cells dep on stimulus |
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Likely diagnosis for LN aspirate with up to 90% medium to large lymphocytes (immature or blasts), sparse plasma cells, mitotic figures
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Lymphoma. NB can also see mitotic figures in reactive LNs
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LN aspirate containing 30-70% medium and large lymphocytes - differential/s?
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Could be reactive or neoplastic. If a germinal centre happened to be aspirated, it would be normal to have increased numbers of medium and large cells
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What types of cells are acceptable in a LN aspirate?
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Round or inflammatory cells
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If a LN aspirate contains epithelial cells or mesenchymal cells, how did they get there?
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Metastasis, or collected by accident
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What would you expect to find in a chylous effusion?
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Lipids, mature lymphocytes, macrophages, often neutrophils.
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How do we differentiate a chylous effusion from septic exudate if it looks the same?
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Lab - triglycerides
Sit 24 hrs - fat to top Spin it down - stays white, whereas a septic exudate the supernatant would go clear as No move to bottom |
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If we see haemosiderin in macrophages - what can we deduce?
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Chronic process - because they have had time to migrate and start phagocytosing.
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Mesothelial cells - characteristics
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Pink frill around outside
Reactive ones look malignant Mesotheliomas can look benign or malignant, difficult to diagnose Is its own class - not round, epith or mesenchymal |
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Four emergencies to look out for on a blood smear
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1. IMHA (spherocytes and agglutination)
2. Leukocytosis w left shift (severe inflammation, the "P"s) 3. Leukaemia 4. Thrombocytopaenia |
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How do we differentiate metamyelocytes from monocytes?
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Look the same but monocytes are bigger
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Characteristic of normal joint fluid cells
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Low cellularity (<3-4 per hpf)
Mononuclear cells present - can't diff btn macrophages and synoviocytes |
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Four things to look for in rbcs in a blood smear
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Number, size, shape, colour.
Reticulocyte count. |
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Two things to look for in wbcs on blood smear
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Total number, proportion,type of wbcs. Count and type at least 100.
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What do we look for in thrombocytes in blood smear?
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Are there enough? r/o thrombocytopenia. Don't worry about morphology
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Four structures you may see on an ear smear
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Cells (squames), No if inflamed
Bacteria (a few is normal) Yeast (malassezia, <10 per hpf is normal) sticky brown material Mites (esp cats) black granular material on swab |
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When should you swab an ear for C&S and why?
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1. If not responsive to tx
2. Whenever you see rods - can cause nasty infections with irreversible damage. In meantime put them on baytril - powerful and broad spectrum. Tx systemically and topically if TM is intact |
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What types of bacteria are rods in ears?
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Pseudomonas and Proteus
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How do you check for mites in ears?
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Swab - look at slide before staining. Huge and moving so can see on 10x.
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3 things most likely to see in feathered edge of blood smear
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Platelets - get dragged out there
Large cells Parasites |
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What causes keratocytes?
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Fragility of cell membrane. Helmet cells, blister cells, apple cells
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3 causes of red cell fragility
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DIC, haemangiosarcoma, iron deficiency
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2 causes of microcytosis of rbcs
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Iron deficiency, portosystemic shunt
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Most common cause of iron deficiency?
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Chronic bleeding - into gut or bladder
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3 causes of petechiae
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Indicates primary haemostatic defect.
Decreased number of platelets Decreased von willebrand factor Defectes in platelets |
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What do platelets look like?
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Pink and hairy and tiny
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How would we differentiate DIC from IMT?
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Clotting profile - DIC, everything prolonged. IMT, normal
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7 yo huntaway bitch, slow, collapsed. Decreased number rbcs, anisocytosis, large lymphocytes (lymphoblasts). Diagnosis?
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Leukaemia - prob lymphoblastic leukaemia
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Dog w severe leukocytosis, neutrophilia with left shift - Ddx?
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Something localised, one of the Ps
Pleuritis, prostatitis, pyometra, pneumonia, peritonitis, pyelonephritis, pancreatitis |
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3 Ddx for a swollen painful joint in a dog?
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Infectious, immune-mediated, neoplasia
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Canine cutaneous histiocytoma:
1.Signalment 2. Location 3. Appearance: 4. Value of cytology 5. Prognosis 6. Do cats get it? |
Any age, most common 6mths - 4yrs
Head, ears, neck, feet Discrete raised dermal mass, ulcerates Cyto high value - avoids sx, regresses Excellent prog. Cats don't get it |
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Lipoma
1.Signalment 2. Location 3. Appearance: 4. Value of cytology 5. Prognosis 6. Do cats get it? |
>8yr old fat dogs
Ventral trunk, axilla, groin - places where there is lots of fat Deep dermal or SQ soft, dscrete, easily movable Cyto good but can't ddx btn lipoma and normal SQ fat Excellent prog. Cats can get it Decrease in size if dog loses weight |
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Follicular cyst (and nevus/hamartoma)
1.Signalment 2. Location 3. Appearance: 4. Value of cytology 5. Prognosis 6. Do cats get it? |
Follicular cyst aka epidermal inclusion cyst, dermal cyst, sebaceous cyst. Malformed follicle fills up with keratin. Nevus = focal aggregation of dermal collagen or adnexal structures, increased collagen can disrupt normal follicular structure - follicular cyst. Severe inflamm rxn if rupture, keratin into dermis.
Any age Dorsum often but can be anywhere Solid or fluctuant discrete mobile nodule Cyto high value but can't ddx from benign follicular tumour excellent prog. Cats do get it. |
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Sebaceous gland adenoma/nodular hyperplasia
1.Signalment 2. Location 3. Appearance: 4. Value of cytology 5. Prognosis 6. Do cats get it? |
Hyperplastic or benign neoplastic lesions of sebaceous glands.
Older animals esp greasy coat Limbs, eyelids, trunk Look like warts. Cyto - good but can't ddx between hyperplasia or adenoma excellent prognosis Cats get but uncommon |
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Basal Cell tumour
1.Signalment 2. Location 3. Appearance: 4. Value of cytology 5. Prognosis 6. Do cats get it? |
aka trichoblastoma
Basal cells are the epithelial cells that form the base of the epidermis, follicles and adnexal glands. So BCT are diverse dep on which way they differentiate when neoplastic. Benign, slowly expansile. All breeds, >7yrs old Head and neck Discrete slowly expanding raised dermal mass Cyto excellent Prognosis excellent Very common in cats, cats are pigmented, dogs are not. |
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Mast Cell Tumour
1.Signalment 2. Location 3. Appearance: 4. Value of cytology 5. Prognosis 6. Do cats get it? |
Graded
I (neoplastic cells confined to dermis), II (well differentiated cells in dermis and hypodermis), III (poorly diff cells in hypodermis). Boxers, boston terriers, bulldogs, staffies, beagles, pugs. 8 yrs old average. Any location esp trunk, extremities Appearance highly variable - soft if releasing vasoactive substances Cyto - high value Prognosis Grade I excellent; Grade II Good; Grade III guarded. Cats get but usually benign. Cats also get systemic mastocytosis, poor prog. |
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Haemangiopericytoma
1.Signalment 2. Location 3. Appearance: 4. Value of cytology 5. Prognosis 6. Do cats get it? |
Canine spindle cell tumour, soft tissue sarcoma, neurofibrosarcoma
7-10yrs old Trunk or legs, elbows and stifles Deep dermal to SQ mass. May be adherent to deeper tissue Cyto - good Prog - Locally infiltrative. Need big margins. Common mistake is to "shell out". 20-30% recur. |
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Hepatoid Gland (perianal or circumanal gland) adenoma
1.Signalment 2. Location 3. Appearance: 4. Value of cytology 5. Prognosis 6. Do cats get it? |
Develop from modified sebaceous glands of perianal skin, grow outwardly as visible masses (cf apocrine baddies which are palpable per rectum)
Intact male dogs Perianal skin, sometimes ventral midline or ventral tail Discrete and exophytic. Often chewed. Cyto - high value Excellent prog - castrate. Cats don't get. |
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Benign dermal melanoma
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Haired skin = benign
Non haired skin (mouth, nail bed) = malignant Scottish terriers, airedales, boston terriers, cocker spaniels. 9yrs. Head esp muzzle and eyelids, trunk. Not induced by sunlight in dogs Slow growing dark pigmented wart-like appearance Cyto hugh value - but excise for histo to ddx malignant Benign prog excellent but low potential for malignant transformation so remove. Cats do get it - 50% of their ones on haired skin are malignant. |
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Squamous Cell Carcinoma
1.Signalment 2. Location 3. Appearance: 4. Value of cytology 5. Prognosis 6. Do cats get it? |
Thin skin of ventral abdomen - sunbathing. Can also get in nail beds, present initially as loss of a nail.
Short coated white dogs. Ventral abdo Red patches or plaques, often ulcerated Cyto value moderate - because so superficial. Prognosis - invasive, hard to excise. Met only very late in course of disease. |
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3 types of solar induced tumours in dogs
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Squamous cell carcinoma
Haemangioma Cutaneous haemangiosarcoma |
