14. Chemistry Panels Flashcards

Question

What is the albumin/globulin ratio?

Answer 1

A/G imbalance is often the first sign of a protein abnormality can detect increased or decreased albumin or globulin lvls Both can be reduced in equal proportions, as with hemorrhage - ratio will remain unchanged in this case

Answer 2

>1.00 Albumin > globulin

Answer 3

<1.00 Albumin < Globulin

Answer 4

Soluble protein that converts fibrin to form the matrix of blood clots makes up 3-6% of total plasma proteins decreased fibrinogen, as seen with hepatic insufficiency, means that the time for clot formation is prolonged or the blood will not clot at all Fibrinogen lvls may be increased in acute inflam in lg animals and with tissue damage

Answer 5

metabolism of AAs, carbs, and lipids Synthesis of albumin, cholesterol and plasma proteins (including clotting factors) Digestion and absorption of nutrients related to bile formation Secretion of bile and bilirubin Breakdown and elimination of toxins and drugs

Answer 6

works and sits alongside liver primary func to store bile that is produced by the liver pathology affecting liver or gallbladder may = jaundice, clotting factors, hypoalbuminemia, hypoglycemia, hyperlipoproteinemia, hepatoencephalopathy

Answer 7

no single test that can be performed to fully eval liver dz's of liver tend to be fairly advanced by time they are clinically apparent only 100 tests available

Answer 8

lvls of molecules that liver produces and metabolizes Bile acids - hepatic function test Bilirubin - hepatic function test Molecules that are released when hepatic cells are damaged or with cholestasis (impaired flow of bile)

Answer 9

ALT, AST, ID, GLDH

Answer 10

ALP and GGT

Answer 11

Macrophages in spleen break down hemoglobin > insoluble bilirubin molecules released in process Albumin binds to bilirubin and transports it to the liver Hepatic cells metabolize bilirubin and it conjugates (or binds to) to glucuronide > will become component of bile Conjugated bilirubin passes from liver into intestine where bact convert bilirubin glucuronide to urobilinogen Urobilinogen broken down into urobilin and excreted in feces and urine, or absorbed back into the bloodstream

Answer 12

about 2/3rds It is bound to albumin

Answer 13

When there is an increase of RBC destruction and there are problems with transport or uptake of bilirubin into the hepatocytes

Answer 14

increased when there is an obstruction of the bile ducts

Answer 15

Can measure total bilirubin (uncon/conjugated) as well as separately measures uncon/conjugated bilirubin will help to determine cause of jaundice

Answer 16

bile acids are prod from cholesterol by hepatocytes in the liver they aid in fat absorption and regulate cholesterol lvls bile acids pass into the intestine via the biliary system and are stored in the gallbladder (except in horses) Most of the bile is reabsorbed by the intestine and then processed by the liver, the rest is excreted in the feces

Answer 17

prolonged fasting/starvation diarrhea malabsorptive dz's

Answer 18

When the hepatocytes, biliary or portal systems are impaired bc of chronic hepatitis (viral, bact or fungal) chronic cirrhosis (due to dz, drugs or toxins) Cholestasis, portosystemic shunts (PSS) neoplasia

Answer 19

They are inc due to hepatobiliary dz and dec food intake

Answer 20

bile acid testing not sensitive indicator of hepatic dz in cattle

Answer 21

eating, or smelling food can release bile into the duodenum and increase in serum bile acids

Answer 22

a serum sample is collected after a 12hr fast, a subsequent sample is collected 2hrs after a high fat meal is ingested Horses: a single sample is collected

Answer 23

enzymes that leak out of damaged hepatocytes

Answer 24

catalyze reactions during AA prod > found in tissues where protein breakdown occurs Alanine transaminase (ALT) aspartate transaminase (AST)

Answer 25

catalyze the transfer of hydrogen during glycolysis iditol dehydrogenase (ID) Glutamate dehydrogenase (GLDH

Answer 26

ALT considered to be liver-specific screening test in D/C when liver is damaged, inc ALT lvls are seen within 12hr, will peak at 24-48 hrs and will return to normal within a few weeks For horses, ruminants, pigs and birds, the hepatocytes do not contain enough to be an ALT to be considered liver specific (ID is a better test) ALT also found in cells of kidneys, pancreas and skeletal muscle, therefore damage to any of those organs will result in an inc in ALT

Answer 27

AST is present in cells of liver, RBCs, heart, skeletal muscle, kidneys and pancreas blood AST lvls increase more slowly than ALT lvls but return to normal within a day Most common causes of inc AST are hepatic dz, muscle inflam - strenuous exercise, IM injections or necrosis Hemolysis - spontaneous or artifact - look at sample Can be correlated w/ creatinine kinase (CK) to determine if muscle inflam likely to be the cause of inc ASt in a patient

Answer 28

ID especially helpful for testing liver damage in lg species like sheep, goat, swing, eq and cattle (as opposed to ALT) but ID testing often not readily available in labs ID lvls rise quickly w/ hepatocellular damage or necrosis this enzyme is very unstable in plasma or serum so specimens to be saved, transported or referred out must be frozen

Answer 29

GLDH found in highest con in liver cells of cattle, sheep and goats elated lvls are indicative of liver damage or necrossis in cattle and sheep

Answer 30

plasma and serum lvls of some enzymes are predictably elevated in cholestasis (impaired flow in bile) Metabolic defects in liver cells with use of certain meds due to action of certain hormones (ex. corticosteroids, thyroid hormones)

Answer 31

ALP is enzyme found in osteoblasts in bone, chrondroblasts in cartilage, intestine, placenta and liver Inc ALP in lg breed pups common during bone development; older anims the bones no grow so inc lvl of ALP more common w/ cholestasis Steroid induction in dogs ALP testing not useful in cattle + sheep Most often used for D/C

Answer 32

Primary sounce of GGT is liver in most animals Blood GGT lvls higher in cows, eq, sheep, goat than in D/C GGT found in several other organs including renal, biliary and mammary epithelium elevated GGT lvls suggestive of liver dz, especially obstructive liver dz

Answer 33

results are associated w. other organs - correlating glucose (pancease and liver results), correlating AST and CK (muscle) results hx and clin signs signalment

Answer 34

conserve and elim h2o and electrolytes conserve and elim hydrogen and maintain pH balance conserve nutrients: glucose and protein elim toxins and end products of nitrogen metabolism: urea and creatinine

Answer 35

Renin: an enzyme for controlling blood pressure Erythropoietin Prostaglandins: fatty acids that stim smooth muscle contraction

Answer 36

blood pressure regulation, regulation of acid secretion in the stomach, regulation of body temp and platelet aggregation, activation of vitamin D and controlling inflammation

Answer 37

Blood enters kidney via renal arteries into glomerulus of nephron Almost all water and sm particles pass into collecting tubules Each nephron has parts that reabsorb or secrete certain solutes; the amount of solute that kidney is reabsorbed is pre-decided > renal threshold Approx. 99% of water is reabsorbed by kidney, remaining is urine Tests to eval kidney func are performed on urine and blood

Answer 38

An increase in BUN and creatinine Rarely is just one elevated out of the two

Answer 39

An increase in BUN and creatinine but is now severe enough to cause animal to feel ill. They will be dehydrated, inappetent and lethargic May be V/D, have "uremic" oral and or/gastric ulcers and central nervous dysfunction seen w/ advanced renal disease

Answer 40

Pre-renal azotemia: underlyding cause of azotemia is occurring "before" kidney Renal azotemia: Occuring within the kidney Post-renal azotemia: Occuring after the kidney

Answer 41

dehydration most common underlying cause PVC and TP may be mildly elevated USG is elevated - urine is well concentrated bc animals kidneys are functioning normally and are conserving water

Answer 42

Can be due to renal failure, congenital disorders or pyelonephritis Renal failure can be classified as acute or chronic PCV and TP may be elevated if the animal is dehydrated (often are, especially as dz progresses) Animal may become anemic with end stage, chronic renal disease due to dec prod of EPO USG will be dec (urine will be dilute)

Answer 43

Acute: often very severe, sudden onset, often (but not always) younger animals; may be associated w/ known toxin exposure Chronic: gradual decrease in renal function and onset of clinical signs

Answer 44

An obstruction in the ureter, neck of the bladder or urethra can cause a post renal azotemia These animals are often dehydrated so PCV and TP will likely be elevated USG will be elevated (urine is well concentrated)

Answer 45

Blood urea nitrogen, the principal end-product of AA breakdown in mammals used to eval kidney function due to kidney's ability to filter urea from blood

Answer 46

All urea passes thru glomerulus into renal tubules about half of urea is reabsorbed into the bloodstream and other half is excreted in the urine

Answer 47

urea is not transported into renal tubules as efficiently When blood exits the kidney back into circulation, there is an increased concentration of urea

Answer 48

does not guarantee an absolute diagnosis of kidney disease

Answer 49

dehydration - urea is insoluble, high volumes of water are needed for its excretion in urine High protein diets or strenuous exercise - leads to an increase in protein breakdown

Answer 50

using an automated analyzer or w/ semi-qualitative dipstick

Answer 51

creatinine is formed from creatine (component of muscle) as part of muscle metabolism During muscle metabolism, creatinine diffuses out of muscle cells into body fluids and blood creatinine lvls are influences by animal's muscle mass

Answer 52

normally, blood creatinine active filtered out of blood and into renal tubules - any condition that alters glomerular filtration rate (GFR) will alter the creatinine concentration in plasma

Answer 53

Renal function has to be reduced by ~75% b4 blood creatinine lvls inc - creatinine alone is also not an accurate indicator of renal function

Answer 54

Urea/creatinine limited in use for eval renal dz bc their reference ranges are too wide GFR could be 4x below normal b4 changes in urea and creatinine are observed (both will inc in renal dz) Both urea and creatinine are filtered by the glomerulus but tubular reabsorption of urea can be regulated whereas creatinine stays constant

Answer 55

SDMA - run w/ idexx machines SDMA more sensitive indicator of kidney func - as little as 25% loss of renal func (usually elevated b4 creatinine and BUN are inc) more reliable indicator of kidney func than creatinine bc its kidney specific inc lvls may indicate another dz process affecting kidneys

Answer 56

 Diseases of the kidney at an earlier stage Chronic kidney disease Acute kidney injury Pyelonephritis Upper urinary obstruction Kidney stones Glomerulonephritis Congenital disease

Answer 57

 Other disease processes affecting the kidney Hyperthyroidism Vector borne disease Systemic hypertension Cardiorenal syndrome Lower urinary obstruction Sepsis Neoplasia Drug Toxicity

Answer 58

A protein found in renal tubular cells With ^^ cell injury occurs, cystatin B released in urine inc lvls of Cy-B in urine indicate active kidney injury Able to detect changes earlier, inc ability to recog subclinical changes not used to analyze kidney function

Answer 59

SDMA, creatinine, BUN and USG

Answer 60

proteinuria may indicate glomerular dysfunction Reference ranges avail for K9+fel 2ml urine by cysto needed

Answer 61

 UPC ratio <0.2 = Normal  UPC ratio 0.2-0.4 (0.2-0.5)= Borderline proteinuric  UPC ratio >0.4 (cats), >0.5 (dogs) = Proteinuric

Answer 62

uric acid is by-product of nitrogen breakdown in mammals, normally converted to allantoin and excreted into urine

Answer 63

impaired ability to convert uric acid to allantoin so excrete in urine

Answer 64

makes up 68-80% of total nitrogen that they excrete in urine - w/ renal disease, serum concentrations of uric acid will increase w/ >70% loss of renal function

Answer 65

effective renal plasma flow (ERPF) -utilizes substances that are elim'd by both glomerular filtration and renal secretion GFR - only uses substances that are eliminated by glomerular filtration Urine and blood are taken at specific times

Answer 66

 Creatinine clearance tests – endogenous and exogenous clearance tests, iohexol clearance test  Single-injection inulin clearance test  Water-Deprivation Tests  Vasopressin Response Test  Fractional Clearance of Electrolytes  Inorganic Phosphorus  Enzymuria

Answer 67

require measurement of blood and urine creatinine lvls urinary bladder is cath'd and rinsed out at beginning and end of test all voided urine collected for 24h

Answer 68

iohexol given IV after a 12 hr fast serum samples are taken 2,3 and 4 hrs after admin and sent to a referral lab for eval

Answer 69

 Inulin is excreted entirely by glomerular filtration, therefore it may be the best test for evaluating GFR  Inulin is injected IV after a 12 hour fast  Serum samples obtained at 20, 40, 80 and 120 minutes after injection to measure inulin concentration

Answer 70

to identify whether or not the kidneys are able to concentrate urine Normally anti-diuretic hormone (AKA vasopressin) from brain signals kidney to retain water Tests involve dehydrating patient to point where patient should secrete ADH to promote water retention, and inc urine conc if urine conc does not inc, then indicates lack of ADH, or nephrons that are unresponsive to ADH

Answer 71

PU/PD can be seen w/ renal dz as well as diabetes mellitus and insipidus, cushing's dz and psychogenic polydipsia Kidneys may func normally, may not be getting signal to concentrate urine OR polyuria may be physiological consequence of polydipsia (as physogenic polydipsia) There is basic and modified versions of this

Answer 72

performed when patient is not able to concentrate their urine during water deprivation test exogenous ADH is given, USG and urine osmolality evaluate

Answer 73

calculation that describes the excretion of electrolytes (usually sodium, occasionally potassium and phosphorus relative to GFR Differentiates pre-renal from post-renal azotemia

Answer 74

used to eval glomerular func serum Pi usually reciprocal of serum Ca initially, renal damage that alters the GFR leads to dec urinary Pi and inc Ca Seruma Ca and Pi also effected

Answer 75

evals glomerular funct refers to presence of enzymes in urine enzymes may be present in urine of patient sw/ renal dz like GGT and NAG which are released from damaged renal tubular cells a comparison of enzyme lvls to creatinine can give an indication of the extent of renal damage renal enzyme lvls will inc rapidly after nephrotoxicity

Answer 76

witho exocrine tissue are sm "islands" of cells called islets of Langerhans that mak up endocrine tissues

Answer 77

Alpha and beta cells most important Alpha cells: almost 20% of cells in islets, secrete glucagon and somatostatin Beta: ~80% of cells in islets, secrete insulin Delta: <1% of cells in islets, secrete somatostatin Pancreatic polypeptide cells: <1% of cells in islets, secrete pancreatic polypeptide

Answer 78

Tissue becomes firm and modular and has a limited ability to regenerate

Answer 79

Gland that secrete products thru ducts rather than directly into blood stream Amylase and lipase common enzyme tests to eval for pancreatitis both can be within normal range in cats w/ pancreatitis

Answer 80

primary source in pancreas, also found in salivary glands and small intestine breaks down starches and glycogen

Answer 81

blood amylase lvls inc in: acute and chronic pancreatitis, obstruction of pancreatic ducts, intestinal obstruction/perforation, if there is a dec in DFR, may be inc in amylase Amylase >3x normal range is suggestive of pancreatitis - rise in conc not directly proportional to severity of disease

Answer 82

derived mostly from pancreas breaks down long-chain fatty acids of lipids lvls tend to be normal during early stages of pancreatic dz and gradually inc over time in chronic pancreatic dz, damaged pancreatic cells are replaced with CT that is unable to prod enzymes > both amylase and lipase begin to dec K9+fel lipase can be tested using ELISA immunologic methods - serum cPL and fPL SNAP tests

Answer 83

trypsin is proteolytic enzyme that catalyzes the reaction that breaks down proteins prods exclusively in pancreas trypsin is readily detected in feces, many tests are performed on fecal samples - absence of trypsin in a fecal sample is abnormal, not commonly used

Answer 84

serum trypsin-like immunoreactivity (TLI) is on immunoassay test that uses Ab specific to trypsin and trypsinogen (the precursor to trypsin) to measure lvls in blood used to dx exocrine pancreatic insufficiency (EPI) - lvls will be below the normal range in affected animals May be performed w/ folate and cobalamin (B12) tests as well this test only available for K9+fel Overnight fast required

Answer 85

gland that secrete hormones directly into the circulatory system blood glucose, fructosamine, B-hydroxybutyrate, serum cholesterol and triglycerides as well as urinalysis provide info about pancreatic func

Answer 86

Blood sugar, pancreatic islets respond directly to blood glucose conc> release insulin from beta cells or glucagon from Alpha cells to regulate blood sugar lvls

Answer 87

only insulin. If insulin is under-prod, or under-performing, will be clinically obvious Blood glucose lvls are net balance btw glucose prod (food intake, conversion from other carbs), glucose and storage

Answer 88

glucose uptake and metabolism depends on insulin and glucagon secretion from pancreas If insulin lvls are high, rate of glucose absorption into cells for metab will inc > cause glucose lvls to dec If insulin lvls are dec (DM) glucose is not absorbed and will go up

Answer 89

test challenges pancreas and evaluates the effects of insulin Glucose bolus is given and then blood and urine glucose conc are monitored if adequate insulin prod and cells are responding appropriately, blood glucose lvls should peak about 30m after glucose admin and return to normal within 2hr Glucose should not appear in urine

Answer 90

diabetes mellitus - prolonged hyperglycemia, glucosuria Hyperactive beta-cell tumors - profound hypoglycemia Other concurrent endocrinopathies Test is rarely necessary to dx DM, persistent high blood glucose lvls, glucosuria and a hx for PU/PD, weight loss +/- polyphagia are sufficient for dx Test may be used for animals that are borderline hyperglycemic or to differentiate stress hyperglycemia from DM

Answer 91

cells are doing what they're supposed to do, but in excess ex. betacells prod insulin like crazy (anims look like they've had an OD of insulin

Answer 92

fructosamine is formed when glucose in bloodstream binds to proteins if there is a persistent hyperglycemia, fructosamine lvls will be elevated can be run on some clinic analyzers or may be a referred out test, fasting is not required Test will give us an indication as to what the blood sugar lvls have been doing for the past 2-3wks may be used for long term monitoring of diabetic cats, can also be used to dx of suspect cases of DM

Answer 93

A fasted blood glucose sample is obtained, then patient is injected w/ short-acting insulin Subsequent blood glucose measurements are taken @ 30m intervals for 3hrs If serum glucose fails to drop to 50% of fasting lvl within 30m, then it can be concluded that insulin receptors are unresponsive or the insulin is being antagonized Insulin resistance profoundly affects the anims therapy and px patient needs to be monitored closely for signs of hypoglycemia during test - need to have glucose solution on hand to admin if needed

Answer 94

simultaneous measurement of fasting serum glucose and insulin can identify the cause of hyperinsulinemia Hypoglycemia normally inhibits insulin secretion, however, pancreatic beta cell tumors (insulinomas) are hyperactive and unresponsive to glucose and secrete an abundance of insulin Anims w/ hyperinsulinemia may have a "normal" fasting insulin, but the RATIO is abnormal

Answer 95

the pos and neg ions found in all body fluids of all organisms Func: maintain water balance and fluid osmotic pressure, muscular and nervous func, maintain and activate of several enzyme systems, acid-base regulation

Answer 96

neg ions Chloride, bicarb, phosphate

Answer 97

pos ions Na, K, Ca, Mg, H

Answer 98

The steady state of pH in the body PH describes H ion conc In body every change of pH scale of one number represents a power of ten diff in H+ conc Normal pH is 7.35-7.45

Answer 99

Function of proteins is compromised Acidosis - pH <7.5 = excess of H ions in peripheral blood Alkalosis - pH >7.45 = deficiency of H ions in peripheral blood

Answer 100

normal metab processes will result in prod of acids (lactic acid, ketoacids) buffer systems work to counter the buildup of acids by altering the conc of H ions

Answer 101

respiratory > responds in minutes Renal/metab > responds over days

Answer 102

if blood pH becomes too acidic, bicarb binds to excess H ions > carbonic acid > breaks down to water and carbon dioxide which is removed by respiration Kidney regulate bicarb by reabsorbing or secreting it into the glomerular filtrate in response to blood pH HCO3- + H+ <>H2CO3 <> H2O + CO2

Answer 103

K and H both passively charged ions that move btw intracellular fluid and extracellular fluid A dec in plasma K = K moving out of cells and into ECF, H moves into cell > blood pH more alkaline An inc of plasma K causes opposite. ECF K moves into cell and H moves out > more acidic

Answer 104

proteins bind and release H ions Hemoglobin has the ability to bind CO2 and H Co2 is transported to the lungs and exhaled

Answer 105

Metabolic acidosis or alkalosis Respiratory acidosis or alkalosis Imbalances inter-related if pH imbalance occurs, the resp and renal systems will work to correct abnormality

Answer 106

if RR is dec there is inc of pCO2 (hypercapnia) If RR is inc there is dec of pCO2 (hypocapnia) CO2 reacts w/ water

Answer 107

Resp acidosis: due to dec RR or volume Resp alkalosis: due to inc RR or volume

Answer 108

any condition that results in an accumulation of acids in the body leads to a metabolism acidosis? Ketoacid prod due to DM > dec HCO3- > metabolic acidosis Abnormal elyte conc and loss of acid d/t vomiting > inc relative HCO3 > metabolic alkalosis

Answer 109

elytes are affected by: inc or dec dietary intake, shifts of ions btw ECF/ICF renal loss or retention GI malabsorption resp system *lipemia and hemolysis can affect elyte measurements *arterial samples are ideal for analysis of blood gases; must be analyzed quickly after collection bc room air affects conc of dissolved gases and sample pH

Answer 110

pH: Art(7.40), Ven (7.35) pCO: Art (40), Ven (45) HCO: Art(25), ven (24) pO: Art (95), ven (40)

Answer 111

Na, K, Ca, Mg, H, Cl, bicarb, inorganic P

Answer 112

chem panels measure ions and compounds present in serum/plasma ONLY, does not measure the conc of products in the cell With ECF ions > hemolysis will dilute sample causing lower ion lvls With ICF ions > hemolysis will cause ions to be released and artificially raise ion lvls

Answer 113

major cation of plasma and ECF Main func is water distribution and maintenance of body fluid osmotic pressure Na is filtered by kidney and reabsorbed back into body as needed in exchange for H - vital role in pH regulation of urine and acid-base balance

Answer 114

hypernatremia - in blood sodium conc (in water deprivation, hyperventilation, osmotic diuresis) Hyponatremia - dec blood sodium concentration (V/D, ketonuria, hypoadrenocorticism, CHF)

Answer 115

major ICF cation Important for muscle func, resp, cardiac func, nerve impulse transmission and carb metabolism

Answer 116

Hyperkalemia: inc blood K conc (cellular damage, acidosis, urinary tract obstructions) Hypokalemia - dec blood K conc (low intake, alkalosis, fluid loss d/t v/d, ketonuria, diuresis

Answer 117

can cause fatal cardiac arrest due to an abnormal HR

Answer 118

Plasma as platelets can release K during clotting process - however analyzer type may dictate sample requirements If sample is going to be refrigerated, the plasma should be separated from the cells - refrigeration will cause K tomove from ICF and ECF

Answer 119

predominant eCF anion maintains water distribution, osmotic pressure, normal anion/cation ratio closely related to Na and bicarb lvls Hyperchloremia - inc blood chloride conc Hypochloremia - dec blood chloride conc if sample is to be stored, serum/plasma should be separated from cells to prevent artificial reductions in Cl conc

Answer 120

2nd most common anion in plasma kidneys work to regulate bicarb lvls by excreting excesses after it is reabsorbs what is needed from urine Bicarb lvls commonly estimated from blood CO2 lvls - done by a blood gas analyzer or part of a e- panel or chem analyzer

Answer 121

2nd most common ICF cation found in all body tissues, more than 50% found in bones works closely w/ Ca and phosphorus activates enzyme systems, involved in making and breaking down ACH - imbalance of mg/ca ration = muscle tetany bc of release of ACH

Answer 122

cattle and sheept

Answer 123

more than 99% found in bone remaining 1% help to maintain enzyme activity, plays a role in blood coagulation, neuromuscular excitability and tone (dec ca can also result in muscle tetany), and maintenance of inorganic ion transfer across cell membrane Ca inversely related to P, if one goes up, other goes down

Answer 124

80% found in bone 20% serves to store, release and transfer energy, involved w/ carb metab and is used to prod nucleic acid and phospholipids within serum/plasma, P is in an inorganic form within RBCs, its in an organic form DO NOT USE HEMOLYZES SAMPLES - falsely elevated results separate cells from serum/plasma asap

Answer 125

total # of cations EQUALS total # of anions neutrality is maintained by various buffering systems any diff btw pos/neg is called anion gap chiefly used to ID metabolic acidosis

Answer 126

(Na+K) - (Cl+HCO3) = gap

Answer 127

Dogs: 12-24mEq/L Cats: 13-27mEq/L Inc anion gap: lactic acidosis, renal failure, diabetic ketoacidosis Dec anion gap: often due to hypoalbuminemia > the proteins req to transport bicarb are lacking

Answer 128

CK is enzyme found predominantly in striated muscle cells and to a lesser extent, the brain When skeletal muscle (namely cardiac) is damaged, CK leaks out of cells and = elevated CK in peripheral blood CK is frequently tested if anim has elevated AST but shows no symptoms of liver damage - if elevated CF, would suggest muscular issue (possibly cardiac) if also elevated in CSF w/ non-specific damage to neural tissue (hypoxia, trauma, inflam, space-occupying tumors) - CSF CF can also be useful prognostically in k9 neuro cases and premature foals

Answer 129

seizures, IM injections (repeased IV blood draws) sx, vigorous exercise, electric shock lacerations,b using, hypothermia persistent recumebncy Myositis and myopathies essentially anything that damages the cell membranes, a delay in testing may cause an inc in reported CK lvls

Answer 130

Lactate, or lactic acid, is prod by anaerobic cellular metabolism inc lactate indicates hypoxia or hypoperfusion lactate can be analyzed in plasma, CSF and peritoneal fluid Blood/peritoneal fluid analysis is a dx acid in equine colic cases - in healthy horses, the blood lactate is always higher than in the peritoneal fluid, if horses have a GI disorder such as an impaction or torsion, the peritoneal fluid lactate will be higher than the blood lactate lvls collect sample in fluoride oxalate or lithium heparin tubes hand held lactate meters are available

Answer 131

variety of endocrine orangs and tissues prod and release hormones directly into capills includes: adrenal glands, thyroid and parathyroid glands and the pituitary gland

Answer 132

stressors cause the hypothalamus to secrete corticotropin-releasing hormone > causes the anterior pituitary to secrete adrenocorticotropic hormone (ACTH) > stims adrenocortical growth and secretion Cortisol is import hormone secreted by adrenal glans in mammals - cortisol inhibs both CRH and ACTH release

Answer 133

cushing's dz - excessive cortisol release caused by brain/pituitary tumors, idiopathic hyperplasia of adrenal glands neoplasia of one or both of adrenal gland over-enthusiastic use of glucocorticoids

Answer 134

addision's dz reduced cortisol release may be caused by adrenal atropy, autoimmune dz, neoplasia, medications

Answer 135

To test for hyper/hypoadrenocorticism Evaluates adrenal glands response to synthetic ACTH Degree of glucocorticoid prod is expected to be proportional to adrenal gland's size and development Hyperplastic (cell proliferative) exaggerated adrenal response Hypoplastic (atrophied) - dec adrenal response Test can detect abnormalities but not underlying cause, also evals efficacy of tx

Answer 136

cortisol lvls tested b4 and after ACTH admin accuracy in hyperadrenocorticism is 80% and 50% in dogs Used to eval response to mitotane or trilostane therapy

Answer 137

PU/PU, panting, polyphagia, pot-bellied abdomen, altered fat distribution, alopecia, mild muscle weakness, lethargy Fragile skin syndrome in cats

Answer 138

cortisol lvls are tested b4 and after ACTH admin adrenal glands are unable to respond to the ACTH so post-ACTH cortisol lvls are below normal range

Answer 139

depression, lethargy, lack of appetite, weight loss, V/D, bloody stool, weakness Dehydration and bradycardia

Answer 140

Low (LDDST) - can confirm a dx of cushing's dz or can be used in place of ACTH stim test to dx cushing's dz High (HDDST) - to differentiate btw pituitary causes of hyperadrenocorticism from adrenal causes Dexmethasone is a potent glucocorticoid that suppresses ACTH release

Answer 141

LLDST - adrenal dependent - no cortisol suppression at 4 or 8 hrs post dexamethasone// pituitary dependent - cortisol suppression at 4+/-8hr post dexamethasone HDDST/UHDDST - adrenal dependent - no cortisol suppression // pituitary dependent - cortisol suppresion

Answer 142

dexamethasone is admin IV, ACTH admined by IV 4hrs later - cortisol lvls measured before dex and ACTH admin, and after acth admin Interpretation: inc cortisol after dex + ACTH = hyperadrenocorticism Inc after dex and NORMAL ACTH - hyperadreno Inc after dex and very high acth - pituitary hyer

Answer 143

used as a screening tool to rule OUT cushin's dz if ratio low - very unlikely if ratio is elevated - test further for hyperadrenocorticism

Answer 144

occurs in older horses bc of adenomas of the pars intermedia of the pituitary gland clin signs: PU/PD, polyphagia, muscle weakness, excessive sweating, long hair coat (fail to shed) Lab findings: hyperglycemia + glucosuria (likely bc of insulin resistance) dx w/ overnight dexamethasone suppression insulin and anti-adrenocortical meds not useful, dopamine antagonists may be helpful

Answer 145

Influence metab rate, growth and differentiation of cells Thyrotropin-releasing hormone (TRH) from hypothalamus stims anterior pituitary to release thyroid sim hormone (TSH) TSH enhances thyroid gland growth, funct and release of thyroxine which is prod as T2 (triiodothyronine: active form), T4 (thyroxine; can convert to T3 in tissues) thyroxine inhibs TRH and TSH release

Answer 146

hypothyroidism: dogs, horses, ruminants, swine Hyperthyroidism: cats may attributable to dietary iodine imbalances or exposure to goitrogens in lg anims

Answer 147

clin signs: spontaneous abortion, stillbirths, alopecia, goiter in fetuses Serum T4 concentrations Protein bound iodine lvls in serum Pasture iodine analysis - feed may be analyzed for goitrogenic plants or excess calcium (which dec iodine uptake) Primary glandular dz due to neoplasia, autoimmune dz, or idiopathic atropy much more common than pituitary dz

Answer 148

substances that disrupt the prod of thyroid hormones, interfering w/ iodine uptake in the thyroid gland -brassica spp triggers the release of TSH from pituitary gland and promotes growth of thyroid tissue > goiter

Answer 149

insulin and estrogen inc T4 glucocorticoids, anticonvulsants, penicillin, trimethoprim, sulfamethoxazole (TMS), and others dec T4

Answer 150

measuring free T4, +/- TSH lvls Hypothy: low free T4 and elevated TSH Hyperthy: elevated free T4

Answer 151

T3 - less reliable than free T4 Total T4 (TT4) - will measure anti-thyroid hormones so not as reliable as free T4 thyroglobulin Ab test - canine specific test, used to detect autoimmune thyroiditis thyroid stimulating hormone response test: primarily used for research purposes at this time

Answer 152

in horses, iodine-deficient hypothyroidism is rare since iodized salt is available However, overeating iodion can provoke hypothyroidism and goiter bc excess iodine inhibs thyroid functio

Answer 153

elevated growth hormone (GH) prod by P-gland will cause canine acromegaly Serial assays of GH tests bc dogs w/ acromegaly show consistent lvl of GH GH will fluctuate in a normal dog

Answer 154

func of GIT to digest/absorb nutrients and excrete waste products GI dz are common in anims so specific testing + dx important biopsy may be req to arrive at a definitive dx; func test rule out other dz and confirm need for more invasive procedures

Answer 155

altered gastric secretion or reduced digestive enzymes (from the pancreas and to a lesser degree the sm int) - approx 90% of pancreas needs to be a non-func before clin signs become apparent

Answer 156

often caused by dz of sm int wall or bact overgrowth syndromes - a loss of funct of >50% of sm int in dogs will = short bowl syndrome

Answer 157

blood loss into gut may appear as melena or hematochezia depending on where bleeding is occurring If blood loss less severe, may not be apparent by gross examination of feces If blood loss into GIT suspected, a fecal occult blood test can be run Test will prod a color change if comes into contact w/ hemoglobin or myoglobin - SA will need to be fed a meat free diet for up to 3d prior to testing ensure LA not being supplemented w/ meat or bone meal

Answer 158

d-xylose absorbed in the SI and eliminated unchanged int he urine - relatively easy to trace Primarily in horses and dogs Xylose is given orally and serial blood conc are measured every 30m-4/5hrs abnormal test results suggest malabsorptive problem in SI Vomiting and ascites will dec xylose blood conc Renal dz will lead to an inc xylose blood conc

Answer 159

B vitamins are reduced in anims w/ malabsoprtion issues Folate absorbed in prox int, while cobalamin in ileum bact overgrowth may cause folate lvls to inc and cobalamin lvls to dec Often eval in conjunction w/ TLI overnight fast req prior to blood sampling

Answer 160

Fluids, tissues, feed must be in separate, clean, leak-proof, hard, plastic containers can send serum/plasma, urine, feces, water, suspicious bait, stomach contents (in form of vomit, gastric lavage or post mortem collection) samples must be individually Id'd w/ O's and Vets names, anim name/ID # and specimen type

Answer 161

blood best refrigerated, gut contents may be frozen Necropsy/biopsy tissues > should be placed in a 10% formalin solution in a 10:1 formalin to tissue ratio

Answer 162

Fairly common enviro pollutant - found in old paint, ammunition, car batteries, solder, linoleum, petroleum and roofing products "plumbism", lead poisoning can occur in all species, clin sings = GIT and nervous signs hematology exam = basophilic stopping of RBCs and inc nRBCs w/o anemia

Answer 163

not any specific changes blood collected in EDTA, heparin or citrate may be analyzed for lead at a reference lab Feces, liver, kidney or bone can be analyzed for the presence of lead

Answer 164

Common in ruminants, pigs, horses that ingest feeds containing high nitrate/nitrite conc excessive lvls found in cereals, grasses and root crops heavily fertilized with these, also runoff may contain lg quantities of nitrate

Answer 165

Nitrates > nitrites in feed or GIT > nitrites absorbed from gut dec O-carrying capacity of RBCs by degrading hemoglobin to methemoglobin > blood becomes red - brown in color A dilute diphenylamine solution can test for nitrites in feed, serum/plasma, urine and body fluid samples > if nitrites or nitrates present in sample, turns blue Hemolysis may mask the color change

Answer 166

chems designed to kill rodents inhibs metab of Vit K VK needed for prod of clotting factors (2, 7, 9 and 10) in liver affected anims will have prolonged prothrombin and partial thromboplastin time as blood clotting is impaired a presumptive dx is made on routine coagulation testing and patient response to Vit K therapy

Answer 167

ingestion results in oxidative damage to RBC's > heinz bodies are formed Horses - red maple leaves Cattle - brassica spp Dogs - onions Cats _ acetaminophen Selenium deficient anms more prone to oxidative injury

Answer 168

commonly causes accidental poisoning that can lead to fatal toxicosis in dogs and cats dx can be presumed based on urinalysis and observation of a high conc of Ca-Ox monohydrate crystals 5ml kills cat, 15ml kills med-sized dog formation of urinary crystals causes irreversible kidney damage ethylene glycol > glycolic acid > oxalic acid crystals