Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

LA DX & TX II > Exam 2 - Equine Anemia > Flashcards

Exam 2 - Equine Anemia Flashcards

1
Q

what hormone is produced by the kidneys that erythropoiesis is dependent upon? why is this important to remember for animals with chronic renal failure?

A

erythropoietin

chronic renal failure animals will often have a non-regenerative anemia due to loss of erythropoietin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

what is the action of erythropoietin?

A

stimulates the bone marrow to crank out RBCs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

when is erythropoietin released by the kidneys?

A

in response to renal hypoxia

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

how do you determine if anemia is regenerative in most species? does this work in horses? why?

A

look for the presence of reticulocytes

doesn’t work in horses - reticulocytes are not released into circulation even with highly regenerative anemia!!!!!!

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

what do we use to determine if a horse has a regenerative anemia?

A

RBC regeneration is determined by RBC size & bone marrow aspirates

macrocytosis - increased MCV - correlates with regenerative anemia

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

how long do equine RBCs live in the bloodstream?

A

normal - remain in circulation for 150 days before removal via mononuclear phagocytes in the spleen, liver, & bone marrow

after this - heme is converted to biliverdin & then to bilirubin which is released unconjugated into the bloodstream

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

what RBC indices are decreased in a horse with iron deficiency anemia?

A

MCV - mean corpuscular volume & MCH - mean corpuscular hemoglobin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

what RBC indices are increased with intravascular hemolysis?

A

MCH - mean corpuscular hemoglobin & MCHC - mean corpuscular hemoglobin concentration

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

T/F: rouleaux formation in horses is a normal finding on a blood smear

A

true

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

what is a poikilocyte?

A

any abnormally shaped erythrocyte

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

what is anisocytosis?

A

variability in RBC size usually associated with an increased RBC distribution

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

what is polychromasia?

A

variability in RBC color, usually due to variable hemoglobin concentration

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

what is a spherocyte?

A

sphere-shaped RBC that may be observed in hemolytic anemias

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

what are echinocytes?

A

‘burr cell’ - short, regularly spaced spicules projecting from the cell surface

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

what are acanthocytes?

A

spur cell with irregularly shaped spicules extending from the RBC surface that are associated with liver disease or gi malabsorption

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

what are elliptocytes?

A

ellipsoid or oval erythrocyte found in animals with iron deficiency or myelophthisic anemia

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

what are leptocytes?

A

thin, flat RBC frequently associated with hepatic disease or iron deficiency

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

what are codocytes?

A

target shaped cell with dense central area of hemoglobin surrounded by a pale zone that is associated with hypochromic anemias or hepatic disease

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

what are howell-jolly bodies?

A

basophilic nuclear remnants seen in the cytoplasm of erythrocytes - normal finding

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

what are heinz bodies?

A

oxidized precipitated hemoglobin indicating oxidative damage to RBCs usually resulting in intravascular or extravascular hemolysis (red maple toxicity)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

what staining is used to best see heinz bodies on a blood smear?

A

new methylene blue stain

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

if you see auto-agglutination on a blood smear, what does it mean?

A

intravascular hemolysis is present

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

what is the difference between a direct & indirect coomb’s test?

A

direct - detects Ig or complement on the RBC surface

indirect - detects anti-RBC antibodies on the RBC surface

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

T/F: to properly evaluate & interpret bone marrow, a CBC MUST be performed at the same time that the marrow sample is collected

A

true

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

what are the advantages of using an FNA for bone marrow evaluation?

A

easier to obtain than a core biopsy

processed & evaluated on the same day of collection

better assessment of cellular morphology

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

what are the advantages & disadvantages of using a core biopsy for bone marrow evaluation?

A

advantages - better assessment for overall cellularity

disadvantages - sample must be fixed, decalcified, sectioned, stained, & processing may take 1-3 days

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

what is the most common collection site used for bone marrow evaluation in adult horses?

A

sternabrae - 4th, 5th, or 6th

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

why avoid using the 7th sternabrae for a bone marrow biopsy in a horse?

A

heart lies adjacent to it - avoid cardiac puncture

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

what is myelophthisis?

A

reduction in all cellular elements in bone marrow - seen in bone marrow fibrosis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

what does the presence of myelodysplasia indicate?

A

presence of abnormal cells - myeloproliferative neoplasia

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

what is myelodysplasia?

A

type of cancer in which the bone marrow does not make enough healthy blood cells (white blood cells, red blood cells, and platelets) and there are abnormal cells in the blood and/or bone marrow

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

how would you diagnose hemoabdomen in a horse?

A

use an ultrasound to evaluate for hemoperitoneum - will see free echogenic fluid in the peritoneum & swirling of cells may be seen

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

what are signs of hemoperitoneum in a horse?

A

clinical signs resemble acute colic!!!

hypovolemia - tachycardia, tachypnea, pale MM, crt >2, & elevated lactate

ultrasound - free echogenic fluid with swirling cells

abdominocentesis - peritoneal fluid with a high PCV & protein

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

how do you manage a horse with hemoperitoneum?

A

hemodynamic stabilization

fluids/transfusions

prognosis depends on severity of bleed & underlying cause

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

how do you diagnose hemothorax in an adult horse?

A

clinical signs of pleural effusion, anemia, or hemorrhagic shock

ultrasound & thoracocentesis for pleural fluid analysis

auscultation, palpate for rib fx, coagulation panel, & look for pleurodynia

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

what does fresh blood look like on ultrasound?

A

hyperechoic, swirling pattern

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

how do you manage a horse with hemothorax?

A

conservative if patient is hemodynamically stable - treat underlying causes (stabilize any rib fractures)

pleural drainage if volume/blood is producing hypoxemia/respiratory distress

prefer not to drain until hemorrhage has stopped

broad spectrum abx, iv fluids, & transfusions if needed

38
Q

what are some causes of intestinal blood loss in horses?

A

post-op from: enterotomy, intestinal R&A, or treatment

stomach ulcers

ulcerative colitis

melena

39
Q

what are some examples of causes of pulmonary hemorrhage in horses?

A

exercise induced pulmonary hemorrhage

massive pulmonary thromboembolism (tachycardia, epistaxis, hemoptysis, & sudden death)

inhalation of foreign bodies

coagulopathy

neoplasia/pulmonary abscessation

40
Q

why would we give a horse IV phenylephrine?

A

help with nephrosplenic entrapment

41
Q

T/F: horses older than 15 that are given phenylephrine for nephrosplenic entrapment are at a 64x greater risk of hemorrhaging

A

true

42
Q

why do we see hemorrhage in peri-parturient mares?

A

major uterine arteries!!!! fibrosis of arterial walls causes loss of elasticity

affects 2-3% of broodmares, compromises 17% of post-partum emergency admissions, & accounts for 40% of post-partum deaths in mares

43
Q

what are some risk factors for hemorrhage in peri-parturient mares?

A

older age

multiparity

dystocia

previous hemorrhage

44
Q

when do we see hemorrhage in peri-parturient mares occur?

A

usually develops within 48 hours after parturition

can occur as early as the 5th month & as late as 4 months after parturition

45
Q

what are some clinical signs of hemorrhage in peri-parturient mares?

A

colic, hypovolemic shock, vaginal bleeding, ataxia, & recumbency

clinical pathology - recent blood loss, PCV/TP often still normal but will decline over time

46
Q

how is hemorrhage in peri-parturient mares diagnosed?

A

ultrasound (transrectal or transabdominal)

47
Q

why do most clinicians avoid trans-rectal palpation for diagnosing hemorrhage in peri-parturient mares?

A

palpation can disrupt the clot - extreme caution

48
Q

T/F: complications occur in 80% of surviving mares with peri-parturient hemorrhage

A

true

49
Q

what are some common complications seen in surviving mares with peri-parturient hemorrhage?

A

fever, retained fetal membranes, laminitis, arrhythmias, colic, colitis, & peritonitis

50
Q

how is hemorrhage in peri-parturient mares treated?

A

cardiovascular stabilization - correct hypovolemia

pro-coagulant drugs

pain management

abx

anti-inflammatories

avoid surgical exploration unless you suspect a GI lesion

51
Q

what is idiopathic renal hematuria?

A

syndrome characterized by the sudden onset of gross, often life-threatening hematuria with hemorrhage arising from one or both kidneys with an unknown etiology

52
Q

what is the common signalment of horses affected by idiopathic renal hematuria?

A

over 50% of cases reported - arabians

no sex or age predilection

53
Q

what are the clinical signs seen with idiopathic renal hematuria?

A

hematuria

hemorrhagic anemia - tachycardia, tachypnea, pallor, & can have hemorrhagic shock

blood clots in bladder & kidney seen from ultrasound or endoscopy

54
Q

how is idiopathic renal hematuria diagnosed?

A

diagnosis of exclusion - must rule out systemic disease, other causes of hematuria, & alterations in hemostasis

55
Q

what is seen on endoscopic examination in a horse with idiopathic renal hematuria?

A

reveals no abnormalities of the urethra & bladder

may see blood clots exiting one or both ureteral orifices

56
Q

how is idiopathic renal hematuria treated?

A

support for acute blood loss

aminocaproic acid or formalin

if unilateral or recurrent, consider nephrectomy

57
Q

why do you have to be aware of renal function of a horse with intravascular hemolysis?

A

in intravascular hemolysis, hemoglobin is released into the bloodstream which is then transported to the liver by haptoglobin

if haptoglobin is saturated, there is free hemoglobin in the blood which is then filtered across glomeruli & reabsorbed by renal tubular epithelial cells

heme is nephrotoxic!!!

58
Q

what are some examples of infectious causes of hemolysis in horses?

A

equine infectious anemia

piroplasmosis

leptospirosis

59
Q

what are some immune-mediated causes of hemolysis in horses?

A

primary IMHA

secondary IMHA - clostridial disease, streptococcal infections, rhodococcus, viruses, lymphoma, & penicillin drug reactions

60
Q

what are some examples of iatrogenic causes of hemolysis in horses?

A

hypotonic fluids, hypertonic saline, formalin, & DMSO if not adequately diluted (always dilute to 10% or less)

61
Q

what is a disease that causes hemolysis in foals?

A

neonatal isoerythrolysis - first 5 days of life

62
Q

what are some oxidative causes of hemolysis?

A

red maple leaf toxicity!!!!!

snake/bee envenomation, phenothiazines, consumption of onion/garlic/rape/kale/pistacia leaves

63
Q

what is IMHA?

A

antibody mediated destruction of RBCs that can occur with or without IMTP

either primary (autoimmune destruction of normal RBC) or secondary

64
Q

what clinical signs are seen with IMHA in horses?

A

fever, lethargy, anorexia

presence of icterus - due to the increase in indirect & total bilirubin

regenerative anemia

hemoglobinuria (pigmenturia)

65
Q

what are some causes of pigmenturia?

A

hematuria, hemoglobinuria, & myoglobinuria

66
Q

how do we differentiate between causes of hematuria?

A

hemoglobinuria & myoglobinuria have no RBC in urine where hematuria does

hemoglobinuria has pink plasma while hematuria will form sediment at the bottom once spun down

myoglobinuria will also have significant muscle enzyme elevations (AST & CK)

67
Q

how is IMHA in horses diagnosed?

A

auto-agglutination of blood on a saline test is strongly suggestive of hemolysis, 100% sensitivity % 87% specificity

flow cytometry - quantification of percentage of RBC that have antibodies (IgG, IgA, IgM) bound to the surface, more sensitive than coombs testing

68
Q

T/F: flow cytometry can differentiate between primary & secondary IMHA

A

false - can’t

69
Q

how are horses with IMHA managed?

A

immunosuppressive drugs!!!!

dexamethasone, prednisolone, or azathioprine

70
Q

T/F: horse RBC are more susceptible to oxidant-injury than RBC of other species

A

true

71
Q

why are horses more susceptible to oxidative hemolysis than other species?

A

horses reduce methemoglobin via a lactate-dependent pathway
& they have a decreased glutathione reduction rate

72
Q

what is the pathogenesis of oxidative hemolysis?

A

oxidants in the blood oxidize the heme iron in hemoglobin from Fe2+ to Fe3+ & forms methemoglobin

osidation of sufhydryl group in Hb leads to protein denaturation & heinz body formation which compromises membrane integrity & makes RBCs more fragile

in turn, they are removed from circulation

73
Q

what are some examples of toxic substances that would result in heinz bodies for a horse?

A

kale, garlic, maple leaf, rape, & onion

74
Q

how does a horse get red maple leaf toxicity?

A

they have to eat wilted leaves!!!!! leaves remain toxic for 30 days

usually in the summer or fall following adverse weather

gallic acid though to be the toxin

75
Q

T/F: maple trees in autumn all look red

A

true, red maple, silver maple, & sugar maple

76
Q

T/F: fresh red maple leaves aren’t toxic

A

true

77
Q

how much wilted red maples leaves will cause clinical signs?

A

ingestion of 1.5mg/kg will produce symptoms

3 g/kg is fatal

78
Q

what clinical signs are seen in a horse with red maple leaf toxicity?

A

tissue hypoxia, lethargy, tachycardia, tachypnea, fever, hemoglobinuria, colic, renal insufficiency, muddy brown/chocolate brown/icteric mucus membranes

79
Q

what abnormal laboratory values do you expect to see in a horse with red maple leaf toxicity?

A

anemia, azotemia, leukopenia/leukocytosis, total methemoglobin elevated (normal is <3% of total hemoglobin), heinz bodies, & hemoglobinuria

80
Q

what is the prognosis of red maple leaf toxicity in horses?

A

very guarded

81
Q

what are some complications seen in horses with red maple leaf toxicity?

A

fever is most common

followed by colic, laminitis, DIC, & cecal impaction

82
Q

how is a horse with red maple leaf toxicity treated?

A

supportive care/iv fluids/pain management/transfusion if needed

mineral oil - reduce further absorption of toxin

ascorbic acid as an antioxidant

vitamin c (30-50 mg/kg IV every 12 hours diluted in saline)

corticosteroids to decrease RBC destruction

83
Q

what clinical signs does pistacia leaf toxicity cause in horses?

A

similar to red maple leaf toxicity

hemolytic anemia, methemoglobinemia, renal failure, & death

84
Q

what is pistacia leaf toxicity?

A

plant that is found in the SW/SE USA - syndrome similar to red maple leaf toxicity, leaves of the plant contain gallic acid

85
Q

what is this toxic plant?

A

pistacia leaf

86
Q

when do horses eat wild onion?

A

only eaten by horses once all other forages have been consumed

87
Q

T/F: for horses with garlic & onion toxicity, horses will recover once they stop eating it

A

true

88
Q

what clinical signs are seen in horses with garlic & onion toxicity?

A

hemolytic anemia, heinz bodies, & excessive sweating

89
Q

what kind of hemolysis does bee & snake envenomation cause?

A

both intravascular & extravascular hemolysis

90
Q

what clinical signs are seen in horses with bee & snake envenomation

A

intravascular & extravascular hemolysis

thrombocytopenia, profound coagulopathy, increased bleeding, excessive thrombosis, & DIC

91
Q

what treatment is done for horses with bee/snake envenomation?

A

supportive treatment & anti-venom

92
Q

what are known side-effects associated with giving phenylephrine to a horse?

A

epistaxis, hemopthysis, hemothorax, hemoperitoneum, hemopericardium, collapse, & death

LA DX & TX II (44 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions