2011 Flashcards
CS with a C6-T2 spinal cord lesion
- normal mentation and CNs
- UMN hind legs; increase muscle tone, increased reflexes
- UMN or LMN forelimbs (+/- flaccid, reduced reflexes)
- altered CPs all limbs
CS of left cerebral hemisphere lesions
- altered mentation and behaviour
- contralateral proprioceptive and CNs deficits
- leaning to right
CS bilateral trigeminal nerve lesions
- altered jaw tone (lock jaw vs. slack jaw)
- reduced facial sensation bilaterally
- reduced palpebrals bilaterally
Cs of Ixodes holocyclus toxin
- LMN flaccid paralysis affecting all muscles to varied extent
- GI stasis, dyspnoea, ataxia/paresis, lack of gag, palpebral
pathogenesis of canine pancreatitis
- co-localisation of zymogen granules and lysosomes leading to activation of trypsinogen to trypsin (active form) witihin the co-localised organellels
- trypsin activates more trypsinogen and other zymogens
- premature activation of digestive enzymes leads to local damage of exocrine pancreas with oedema, bleeding, inflammation, necrosis and peripancreatic fat necrosis
4.inflammatory process recruits WBCs and cytokine production —> cytokines circulate and lead to distant complications; DIC, hypotension, MOD, disseminated lipodystrophy, pancreatic encephalopathy
discuss known risk factors for canine pancreatitis
- Genetic/hereditary predisposition; Mini Schnauzers, yorkshire terriers, poodles, dachshunds, cocker spaniels
- Dietary Indiscretion + Hypertriglyceridaemia (>500mg/dL)
- Severe blunt trauma; ie. HBC
- Pancreatitis hypoperfusion; ie. GA, shock
- Infectious diseases; Babesia canis, Leishmania
discuss the use of PLI
pancreatic lipase immunoreactivity is specific for the measurement of pancreatic lipase concentrations in serum and is thus the most specific diagnostic test for pancreatitis, and highly sensitive
1. in clinic tests; (semiquantitative evaluation of seurm pancreatic lipase immunoreactivity) SNAP cPL –> positive suggestive of pancreatitis, negative suggests that pancreatitis is very unlikely
2. Spec cPL(seurm sample); confirms diagnosis and determines a baseline concentration
total T4 for canine hypothyroidism
1.Define test: total t4 is a measurement of circulating thyroxine; it should be low in dogs not producing adequate thyroid hormones
2. Indications: Clinical suspicion is present; lethargy, mental dullness, decreased appetite, cold intolerance, weight gain, alopecia (rat tail), GI signs
3. Limitations: multiple factors can cause low T4 in euthyroid patients, ~50-60% of dogs have low TT4 at some point in the day, breeds (sighthounds), drugs (TMS, pheno, clomipramine, glucocorticoids), obesity, estrus, pregnancy, + euthyroid sick syndrome (HyperA, hypoA, infection, DM)
4. Interpretation; sensitivity of TT4 alone for diagnosing hypoT is ~75%, specificity ~95%. If TT4 conc >2mg/dL can rule out hypoT, but need to assess TSH + fT4 to diagnose
UPCR
- Define: urine protein: creatinine ratio allows quantitative measurement of suspected renal proteinuria. It is a unitless number obtained by dividing urine protein (mg/dL) by urinary creatinine (mg/dL). Important ; a form of CKD, substage in IRIS staging, progressive damage to nephrons, can lead to hypoalbuminiaemia + more, prognostic)
- Indications: suspicious of renal proteinuria (glomerular/tubular) + inactive sediment
- Limitations: can be elevated with contamination of urine; haematuria, pyuria, semen. day to day variability (low UPCs ~1.0 can vary daily up to 80%, higher UPCs 12.0 ~ 35% variability).
- Interpretation: Determine type of proteinuria (post-renal, pre-renal (Bence Jones proteins, myo/haemoglobin), renal (functional ie. heat, stress, fever, seizures - should resolve in 1 week, pathological)
- pathological renal proteinuria; glomerular (filtration barrier disruption) vs. tubular (impaired ability to resorb protein).
fructosamine assay in feline DM
- Define: fructosamine is formed from irreversible binding of glucose to amino groups in plasma proteins. Fructosamine conc. reflects mean BG concentration over the last 1-2weeks. Most newly diagnosed diabetic cats have fructosamine levels 7.21mg/dL (>400umol/L). Fructosamine levels are unaffected by stress.
- Indications: to differentiate between stress induce hyperglycaemia and DM
- Limitations: diabetic cats with concurrent hyperT or hypoproteinaemia may have normal fructosamine levels due to lower plasma protein levels and rapid protein turnover rates, thus unreliable in cats with concurrent hyperT. Cats with mild DM or recent onset (<1-2wks) may have normal fructosamine levels.
- Interpretation: used to confirm DM diagnosis
Pathophysiology of paraneoplastic syndrome; gastroduodenal ulceration + associated neoplasms
- mast cell tumour (MCT) is the most common cause –> hyperhistaminaemia
- histamine stimulates gastric acid secretion, and exerts direct effects on the gastric mucosa causing increased vascular permeability and mucosal blood flow, in addition to protein exudation
- gastrinoma; a gastrin-secreting pancreatic tumour
Pathophysiology of paraneoplastic syndrome; hypoglycaemia + associated neoplasms
- functional beta cell tumours of the endocrine pancreas (insulinomas) are the most common cause; others - hepatocellular carcinoma, smooth-muscle tumours of the GIT (leiomyoma, leiomyosarcoma, GI stromal tumour)
- cause of hypoglycaemia in these latter tumours is uncertain but may be related to excess tumoral consumption of glucose, decreased hepatocellular function (in the case of hepatocellular carcinoma), or ectopic production of insulin-like growth factors (IGFs)
Pathophysiology of paraneoplastic syndrome; hypergammaglobulinaemia + associated neoplasms
- globulins = all the non-albumin proteins in circulation (including clotting factors, enzymes hormone-binding proteins, lipoproteins, immunoglobulins)
- IGs produced by plasma cells and mediate the humoral immune response to pathogens/inflammatory stimuli
- polyclonal gammopathy = typically seen with infectious/inflammatory diseases
- monoclonal gammopathy = neoplasms; B-lymphocytes or plasma cell cancers - they originate from a single ancestral precursor cell
- most common cause of monoclonal gammopathies; multiple myeloma, solitary plasma cell tumours, B-cell lymphomas, leukaemias, less commonly solid tumours
- important non-neoplastic causes; ehrlichiosis and leishmaniasis in dogs, FIP (cats)
Pathophysiology of paraneoplastic syndrome; thrombocytopaenia + associated neoplasms
- decreased platelet production, increased destruction or consumption, sequestration and loss by haemorrhage
Pathophysiology of paraneoplastic syndrome; aenamia + associated neoplasms
- lymphomas, leukaemias, multiple muelomas, histiocytic sarcoma, haemangiosarcoma
- associated with haemorrhage, IMHA, oxidative injury to RBCs, tumour cell erythrophagocytosis, myelophthisis
+ myelosuppressive chemo effects, anaemia of chronic disease
