Approach to cases

Question 1

DDX for abdominal effusion and tests to perform

Answer 1

Increased hydrostatic pressure –> portal hypertension thus prehepatic (portal thrombus, neoplasia); hepatic (PRESINUSOIDAL: PHPV, ductal plate malformations,
SINUSOIDAL cirrhosis, chronic hepatitis or cholangiohepatitis, ductal plate malformations, lobular dissecting hepatitis; POSTSINUSOIDAL - veno-occlusive disease)
and posthepatic (RSCHF, tamponade, intracardiac neoplasia, extraluminal neoplasia, thrombus)

Decreased oncotic pressure (low alb) - PLE, PLN, liver failure

Investigation - focus on low albumin if present

Otherwise imaging +/- BaTT/NH3 for liver dysfunction though they are insensitive.

Question 2

Approach to modified transudate or exudate abdominal effusion

Answer 2

Modified transudate = TP >2.5-5 (>2.5 can be exudate); TNCC 1500-5000 (exudate >5000)

Cytology, lactate, glucose, PCV, TG, creatinine, bilirubin, FIP tests, Cultures and imaging

Modified transudate can be chronic low protein effusion so same differentials apply. More likely to see neoplasia or potentially a mild sterile peritonitis

Exudate think FIP, biliary or GI rupture, FB migration, neoplasia, splenic/hepatic abscesses, urinary tract rupture

Question 3

Systems to consider in any patient with collapse or weakness

Answer 3

SYNCOPE- no movement, flaccid collapse, no loss of voiding function. May be cardiogenic (sinus arrest or AV block of rapid tachycardia) or neurocardiogenic (tussive, vasovagal)

Non-syncopal collapse
Cardiovascular - arrhythmia, output failure, hypotension

Respiratory - upper airway collapse (lar par, DAD, BOAS), severe pulmonary disease

Neurogenic - Paroxysmal movement disorder; neuromuscular disease (MG, hypoTH, DM, tick, snake, botulism, myopathy), exercise induced collapse

Metabolic - HypoK, hyperK, hypoCa, hypoglycemia, hypoadrenocorticism, hypotensive shock, sepsis/toxaemia

Question 4

Causes of dysphagia

Answer 4

Obstructive lesion (anatomic or mechanical)
- FB, neoplasia, inflammatory mass, lymphadenopathy, sialocele, cricopharyngeal achalasia or dyssynchrony, cleft palate, TMJ disease

Pain
- dental
- stomatitis
- Trauma
- Retrobulbar abscess

Neurologic
Brainstem
Peripheral neuropathy or junctionopathy
CNs V, VII, IX, X, XII
(MG, polyrad, inflammatory myopathy or neuropathy)
Rabies

HypoTH

Question 5

DDx for PUPD

Answer 5

CDI
Primary NDI

Secondary NDI (endocrine, infectious (lepto, pyelo), liver, hypoK, hyperCa, erythrocytosis, Lepto, Acromegaly)

Osmotic diuresis
(DM, ketones, primary renal glycosuria, Fanconi, post-obstructive, high salt diet)

Low renal medullary tonicity (washout from diuresis, liver disease)

SIADH
Phaeochromocytoma
Splenic HSA

Question 6

Approach to micturition disorders

Answer 6

If voluntary bladder control present:
–> assess residual volume, if normal then consider sphincter weakness, central disease causing abnormal micturition (cerebellar)

–> normal micturition with abnormal residual volume: if no abnormal neurological findings consider detrusor dyssynergia

Absence of voluntary control of urination
–> no residual volume suggests either a central cause of abnormal micturition (cerebral cortex) or behavioural

–> lack of voluntary control with residual volume (detrusor reflex not working):
check perineal sphincter reflex –> if absent then S1-3 lesion
–> if present then consider UMN bladder (pons to L7 lesion) or pelvic nerve lesion

Question 7

Approach to fever

Answer 7

DDx: infection
(focal bacterial abscess/granuloma/endocarditis or disseminated lepto, anaplasma, Ehrlichia)
Viral (CDV, CPV,, FPV, FCV, FHeV, FIP,
FIV/FeLV);
Fungal - crypto, Asper, sporotrichosis
Protozoal - Babesia, Toxo, Neo
Neoplasia (lymphoproliferative, myeloproliferative, solid, necrotic),
Inflammatory process (immune mediated, steatitis

If no localising signs and acute onset with mild presentation wait 5 days
Can do basic infectious disease testing like FIV/FeLV

Radiographs f respiratory signs or areas of pain. U/s if abdominal pain.
Ensure dog not been in oestrus recently if entire.

After 5 days then further imaging, sampling, joint taps, ANA titres, blood cultures, bone marrow aspirates, serology for tick borne disease or viral infections, echo, LN aspirates even when normal.

Question 8

Causes of peripheral cyanosis

Answer 8

absent pulses = arterial thromboembolism

Normal pulses = reduced cardiac output/arterial supply: shock, heart failure, dehydration, hypothermia
OR venous obstruction - neoplasia, tourniquet, venous thrombosis, RSCHF