Diagnostics Flashcards
Knowing a patient’s serum electrolyte levels, how can you calculate the anion gap?
Anion gap=(Na+K)-(Cl+HCO3)
The combo of proteinuria, hypoalbuminemia, hypercholesterolemia,and peripheral pitting edema is pathognomic for:
Nephrotic syndrome
Which serum electrolyte abnormality suggested by absence of a P wave on an ECG?
Hyperkalemia
When drawing blood from a ferret for hematologic and biochemical panels, which two venipuncture sites are commonly used that provide the appropriate sample volume (about 1.5 ml)?
The jugular vein and cranial vena cava
Small numbers of Howell-Jolly bodies are a normal finding in which large animal species?
Equine
After what approximate period of time from the onset of anemia would you expect a maximum erythropoietic response from the marrow?
7 days
What is the anticoagulant of choice in test tubes used for coagulation testing and blood typing?
Citrate (blue tops)
Which common characteristic of large animal urine can cause a false positive result for urinary protein?
Strongly alkaline urine
Blood zinc levels must be measured on blood drawn specifically into special tubes. Why?
Other tubes have rubber tops that contain zinc, causing falsely elevated results
How can you explain that hyperlactetemic calves have a normal blood lactate measurement?
They predominantly have high circulating d-lactate levels, whereas analyzers measure l-lactate
What is the diagnostic test of choice for leptospirosis in dogs?
Microscopic agglutination test (MAT)
Heat precipitation or electrophoresis of urine is used for detecting which characteristic substance in cases of multiple myeloma?
Bence-Jones proteins
Name 2 reasons of increased anion gap metabolic acidosis
Ethylene glycol toxicity
Diabetic ketoacidosis
Uremic acidosis
Lactic acidosis
What is species specific characteristics of the differential count on the leukogram of cattle and sheep?
Lymphocytes>neutrophils
Creatine kinase (CK) and aspartate aminotransferase (AST) are associated with muscle damage in large animals. Which enyzmes has the shorter half-life?
CK (2 hours in horses, 4 hours in cattle)
Calcium oxalate monohydrate crystals and calcium oxalate dihydrate crystals in dogs: which one is more suggestive of ethylene glycol toxicosis?
Monohydrate-look like picket fence shape; ethylene glycol
Dihydrate-envelope; nutritional or artifact of refrigeration or less commonly ethylene glycol
In sogs, codocytes (target cells), have been specifically linked with the hypercholesterolemia of which endocrine disorder?
Hypothyroidism
The presence of a positive antinuclear antibody (ANA) test, pathologic proteinuria, and polyarthritis should lead to the suspicion of this disease
Systemic lupus erythematosus
What is the diagnostic purpose of placing a rebreathing bag over the mouth and nose of a horse?
Optimizes detection of abnormal lung sounds by increasing tidal volume and thereby the velocity of air flow in the large airways
In Horrner’s syndrome, how can a lesion be localized pharmacologically to determine if it is preganglionic or postganglionic (of the lower motor neuron portion of the pathway)?
Application of a dilute direct acting sympathomimetic to both eyes reveals minimal pupillary dilation if the lesion is preganglionic, and rapid, marked dilation if the lesion is postganglionic
What is the diagnostic blood test of choice, and the expected abnormality, in a case of oragnophosphate intoxication?
Serum acetylcholinesterase levels Low levels (
When performing a myelogram, why is cervical myelography rarely of value when severe thoracolumbar cord swelling is present?
With a cervical injection, only the cranial margin of the compressive lesion may be imaged since the contrast medium flows rostrally into the intracranial ventricular system when resistance to caudal flow is encountered
An 8 month old puppy receiving a raw meat based diet shows multi-limb lameness and overall weakness. bloodwork reveals hypocalcemia and increased ALP. Radiographs show widened physes, particularly at the distal ulnae. What the dx?
Rickets, most likely dietary deficiency of vitamin D. Therapy should consist of a regular diet with adequate and not excessive amounts of calcium, phosphorus and vitamin D.
What is the anticlinal space and where is it found in the cat and dog?
Narrowest thoracic intevertebral disk space
Between 10-11 thoracic vertebrae
11th is the anticlinal vertebra
Which diagnostic test might produce abnormal results consisting of positive sharp waves and fibrillation potentials?
Electromyography (EMG)
Test used for assessing patients with suspected myopathic or denervation disorders
Your heparinized blood gas sample shows markedly hypernatremia that is inconsistent with the clinical picture. Which error likely occurred when obtaining the sample?
Blood was drawn into sodium heparin rather than lithium heparin
There are 3 modes of echo display in diagnostic ultrasound. A standard abdominal ultrasound would be done in: A, B, or M mode
B mode
Why do band neutrophils quickly appear in the blood during acute inflammation in cattle
small bone marrow reserve of mature neutrophils
Legg-Calve-Perthes disease is also known as
Aseptic necrosis of femoral head
Which two hematologic findings on smears of peripheral blood suggest immune-mediated red blood cell damage?
spherocytosis and agglutinated red blood cells
which specific test is used for assessing the function of intrinsic coagulation pathway?
activated partial thromboplastin time (aPTT)
Acatholysis is noted on a skin biopsy. What is the most common cause of this finding?
autoimmune disease such as pemphigus
how would you confirm a tentaive diagnosis of myasthenia gravis?
identify the presence of serum acetylcholine receptor abs
edrophonium testing is considered obsolete
Urine specific gravity in which range is said to be isothenuric?
1.008-1.012. The kidney is neither concentrating nor diluting the urine. with severe dehydration, specific gravity up to 1.020 is still consistent with isosthenuria, since plasma osmolality may be markedly increased
A male lizard is presented for evaluation of recent-onset swelling of the ventral tailbase, adjacent and caudal to the cloacal opening. What is the most likely diagnosis
normal enlargement of the hemi-penes with sexual maturity
abnormal debris accumulation (seminal plugs)
What is the gestation period for guinea pigs?
59-72 days (average 68 days)
An adult box turtle has a circumscribed, firm subcutaneous swelling in the cranial neck, ventral and caudal to the eye. The diet is not nutritionally balanced. What is the most likely dx?
aural abscess
which infectious disease of rabbits can present with sudden death and eyelid edema?
myxomatosis
What are the veterinary terms for the crop and the gizzard in birds?
ingluvies (Crop) and ventriculus (gizzard)
What is the most common cause of swollen limbs in reptile patients?
fibrous osteodystrophy, resulting from metabolic bone disease
other than respiration, name on biological function of gills of fish
excretion of nitrogenous wastes
osmotic and ionic regulation
acid-base regulation
When providing supportive care for ill birds, what is the optimal environmental temperature range in which they should be kept?
85 to 95 degrees Fahrenheit
Urine cortisol:creatinine is infrequently used for diagnosis of hyperadrenocorticism in dogs. What is its main flaw?
poor specific
many non-adrenal disorders cause a false positive result
What is the Morgan line?
a radiographic finding that represents the formation of enthesiophytes on the caudal aspect of the femoral neck, medial to the trochanteric fossa. It occurs as a result of early degenerative joint disease of the coxofemoral joint
Name the most common laboratory test abnormalities identified in acute canine Anaplasma phagocytophilum infection
Thrombocytopenia
lymphopenia
elevated serum ALP
elevated amylase
Name 2 disorders which can cause a normal anion gap metabolic acidosis in dogs
diarrhea
renal tubular acidosis
dilutional acidosis (rapid saline administration)
hypoadrenocorticism
Synchronous diaphragmatic flutter in horses is suggestive of which serum biochemical abnorammality?
Hypocalcemia
Wood’s lamp examination is fast and inexpensive when searching for dermatophytosis; however, its major disadvantage is….?
insensitive
only catches 50% of Microsporum canis
When measuring the following parameters in the same patient, which can be expected to be significantly different (eg >25%) in venous blood samples compared to arterial samples? PCO2 PO2 HCO3 pH
PO2
typically 50% lower in venous samples compared to arterial
a patient has an intraocular pressure of 7 mmHg. What is the most likely diagnosis-normal, uveitis or glaucoma?
This patient has uveitis
uveitis (30 mmhG)
What are the reservior animal species for Francisella tularensis subspecies tularensis?
Lagomorphs (rabbits and hares)
In dogs, approximately which proportion of nephrons must be nonfunctional before abnormal concentrating ability of the kidney’s is evident?
2/3 need to be nonfunctional
versus 3/4 for azotemia
With ultrasoound, portal veins are distinguished between hepatic veins by which feature?
Presence of hyperechoic walls in the portal veins
When collecting a blood sample for a CBC, an adequate amount of sample volume must be drawn into the anticoagulant tube. Otherwise, which false result can be expected
Decreasaed HCT because of excess volume of EDTA solution related to sample volume
Which substance is typically present in abnormally high concentrations in chylous effusion?
Triglycerides
What is the dx test of choice for evaluating the magnitude of proteinuria in a dog or cat?
UPC
In the pregnant bitch, mineralized fetal skeletons can be detected radiographically as early as how many days after the LH peak
45 days
A patient has ascites, and the fluid analysis reveals that it is a pure transudate. What is the differential dx?
Severe hypoalbuminemia is the most common cause
Others include: prehepatic portal hypertension and cyst rupture
Sequential radiographs allow evaluation of fx healing in small animals especially in cases requiring surgical stabilization. Generally how often should such follow up rads be taken?
Every 4-6 weeks until healing is complete
What are the 4 ECG characteristics of atrial fibrillation
no P waves
f waves (baseline undulation)
normal QRS comples
irregularly irregular rhythm
The prothrombin time evaluates which pathways of secondary hemostasis?
extrinsic and common pathways
pTT-intrinsic (in a relationship)
pT-extrinsic (exes
If your patient’s pH is high and the pCO2 is decreased, which type of acid-base disturbance does the patient have?
respiratory alkalosis
in dogs, the u/s appearance of a gallbladder mucocele resembles which cut fruit?
the kiwi fruit
What is the mechanism by which von Willebrand factor enables blood clotting?
von Willebrand factor is an adhesive protein that is required for platelet-collagen binding
What is the dx test of choice for salmonellosis (“paratyphoid”) in chickens?
direct bacterial culture, to allow ID of the Salmonella spp
which 2 hematologic findings are indicative of significant oxidative damage?
heinz bodies
eccentrocytes
What are the characteristics of anemia typically seen in “anemia of chronic disease”?
normocytic, normochromic non-regenerative anemia
Grossly, hemorrhagic pericardial effusion can most readily be differentiated from peripheral blood in which way?
it rarely clots
exceptions: cardiac rupture or severely hemorrhaging neoplasm
What is the dx test of choice for exocrine pancreatic insufficiency in cats and dogs?
serum trypsin-like immunoreactivity
cTLI or fTLI
Should brain tissue submitted for rabies testing be refrigerated or frozen?
refrigerated
Would a lower frequency (eg 3 MHz) ultrasound transducer give you more or less penetration for viewing deep abdominal structures?
more penetration
higher frequencies are attenuated more than lower frequencies
therefore increasing the frequency decreases penetration
What are the 2 options for assessing the cardiac rhythm of a patient with arrhythmias that occur only sporadically?
1) Holter monitor (portable continuous ECG recorder-lasts 24 hours)
2) event monitor (portable ECG monitor that the owner triggers when an episode occurs, to record the ECG instantly-lasts 7 days or more)
3) in-hospital monitoring with ECG
Glomerulonephritis can cause severe proteinuria leading to a hypercoagulable state due to the loss of which protein?
Anti-thrombin III
What is the optimal serum concentration of IgG in a 24 hour-old foal?
> 800 mg/dl
When testing serum bile acids in horses, only 1 sample is taken as compared to dogs and cats in which 2 samples are taken. Why only 1 in horses?
because horses lack a gallbladder, there is no advantage in measuring a postprandial sample
Mycobacteria all have which specific microscopic staining characteristic in common?
acid-fast staining
Which in vitro phenomenon may cause false elevation of serum or plasma potassium concentration?
Platelet activation during in vitro clotting or failure to separate serum or plasma from red cells within an hour of collection.
hemolysis rarely causes artifactual hyperkalemia , except in individuals with unusually high intraerythrocytic potassium concentrations (eg Akita, Shiba Inu, Tosa Inu)
