Abnormlaities of the erythrom 2 Flashcards

(36 cards)

1
Q

How can you test for meleana?

A
  • meat free diet (red meat) for 5d before test or will be positive
  • not always visable blood
  • “feacal occult blood” very sensitive but NOT specific
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Causes of increased losses?

A
> haemorrhage (external) 
- meleana
- UT
- Epistaxis
- Post-trauma/surgery
> haemorrhage (internal) 
- bleeding tumour
- trauma
- into tissue (bleeding diathesis) 
- surgery 
> haemolysis 
- ^ internal RBC destruction 
- intra v extravascualr
- normal erythrocytes or abnormal/damaged ?
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What is the most common form of haemolyss? Dxx?

A

> IMHA

  • anti-redcell Ab (IgG, IgM, IgA)
  • red cells opsonised -> lysis (IgM) or phagocytosis
  • may agglutinate
  • Coombs test + (for anti RBC Ab)
  • may be severe/rapid, usually strongly regenerative
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What is seen microscopically with IMHA? Ddx?

A

> agglutination
- flaky blood macroscopicallly
- grape like bunches of RBC
- in saline agglutination test (screening)
- one drop saline one EDTA anticoagulated blood mix on slide
- look for flecking before starts to dry (will still occour if AGGLUTINATION, will get rid of ROULEUX artefact)
Ddx = Rouleaux artefact
- stack of coins
- high protein stuck on RBC
- gritty, lumpy macroscopically
- but not pathological

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

What causes intravascular haemolysis? How is this seen?

A

> complement mediated

- ghost cells (barey visable, membrane still present, Hbg gone)

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

What causes extravascular haemolysis?

A
  • macrophages in liver/spleen
  • takes bites out of lipid bilayer -> spherical cell (spherocytes) as membrane reforms
  • smaller, and very dark (no central pallor)
  • normal volume though diameter will appear less
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What else may be found with IMHA? Dxxx

A
  • ^ bilirubin (esp with extravascular breakdown)
  • neutrophilia, monocytosis (marrow upregulation)
  • patelets may also be affected (Evans syndrome IMHA+ platelets)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What parasites may cause haemolysis?

A
> mycoplasma haemofelis and M. haemominutum (formerly haemobartonella) 
- epicellular
- large and small forms 
- ^ fragility and hameolysis
- cyclical 3-8 weeks 
- not in UK 
> Babesia (dogs, USA, mediterranean) 
- tick borne dz
- pyriform bodies INSDIE RBC 
- haemolytic
> Cytauxzoon felis (US) 
- intracellular
- prominant splenic RBC removal
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Dx of mycoplasma haemofelis?

A
  • PCR excellent

- blood smear not reliable

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

Tx babesia?

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

Which animals develop Heinz bodies more readily?

A

Cats

- low number unremarkable in cats

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

What are heinz bodies and how do they appear?

A
  • denatured/oxidised Hbg

- Little ‘nose’ on cell, same colour of RBC

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

Causes of Heinz body formation?

A
  • onions
  • paracetamol
  • Vit K
  • propylene glycol
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What are eccentrocytes?

A
  • Hbg uneven distribution within the cell -> eccentric distribution
  • oxidative damage to membrane (cf. Heinz - Hbg)
  • seen most commonly in dogs, seen horses with red maple toxicosis
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What are schistocytes and keratocytes?

A
  • Shear injury products d/t microangiopathic dmage (tumours w/ narrow vessels eg. angiosarcoma) or organ inflammatory beds (severe hepatitis, DIC) d/t fibrin stranding cutting them in half
  • Clue to underlying disease vs cause
    > schistocytes
  • RBC fragments 2* to shear injury
  • assoc with fibrin deposition in vessels and DIC
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What are acanthocytes?

A
  • surface prjections (spicules)
  • variable length, unevenly spacd
  • narrow base and blunted
    > seen with splenic dz
17
Q

Pre-keratocytes and Keratocytes?

A
  • red cells with apposed and sealed membrane
  • helmet shaped cells
  • associated with shearing (intravascular trauma eg. vasculitis, DIC) alongside shistocytes
18
Q

Spherocytes

A
  • extravascular destruction by macrophages taking a bite out -> membrane reforms as a sphere
  • darker and smaller, perfectly round
  • no central pallor
19
Q

Give egs of inherited hemolytic dz

A

> Pyruvate kinase deficiency [Basenjis and Beagles]
- Energy production deficiency
- initially may be very regnerative
- may go on to develop myelofibrosis and acute crisis (death @ 1yr)
- chronic, severe haeolysis
PFK deficiency [English springers]
- RBC sensitive to alkaline ph : low grade haemolysis with severe episodes superimposed
feline porphyria

20
Q

MOst common non-regenerative anemia?

A

> anaemia of inflammatory/chronic disease

  • normocytic, normochromic
  • usually mild and lowly progressive
  • Fe sequestration (bugs want iron)
  • inflam mediators -> shortened erythrocyte survival
21
Q

Causes of non-regenerative anaemia? FINISH

A
  • chronic disease
  • renal
  • endocrine
  • FeLV
22
Q

How does renal anaemia occour? Tx?

A
  • EPO production v
  • normocytic, normochromic, mild - mod
  • impacts quality of life
    > Tx: EPO injections (though human so can => immune response)
    > aim to ^ PCV (though not to normal)
23
Q

Is endocrine anaemia a common problem?

A

Rare

  • hypothyroid and hypoadrenocorticism
  • normocytic, normochromic, mild
  • thyroid hormone and cortisol facultative effect on RBC production
24
Q

How common is FeLV anaemia? How are they linked? What type of anaemia is seen?

A
  • FeLV subgroup C
  • 70% anaemic cats!
  • selective depression of erythropoeisus
  • dyspalstic production
  • myeloproliferative dz ‘crowding out’
    > usually non-specific erythroid hypoplasia
  • may be normocytic/chromic but may be macrocytic
25
Causes of aplastic anaemia
- FeLV, estrogen tox, phenylbutazone, chemotherapy, unknown
26
What is missing with apastic anaemia? What remains? What is needed to dx this?
- ALL precursors (complete non-regenerative marrow) - fat, plasma cells and mast cells left - need core biopsy otherwise cant tell if youve just got a rubbish sample
27
What is myelodysplasia? What is seen in the marrow?
- type of non-regenerative anaemia (pre-leakaemia) - adequate cellularity in marrow but abnormal maturation/proliferation of cells (ineffective haemopoiesis) - in the marrow: erythrocyte macrocytosis, binucleates, maturation defects, giant neutrophils, hypersegmented neuts, macroplatelets - may progress to leukaemia
28
What is myelopthisis?
- neoplasia crowding out the bone marrow and altering environment - usually haematopoetic neoplasia (esp lymphoid)
29
What is myelofibrosis? Dxx?
- response to injury of fibrous elements of marrow -> dry taps - may be reactive following prolonged regenerative attempts - Need core biopsy: reticulin stains up the fibrous elements - osteosclerosis: cortical bone ^ +- marked extramedullary haematopoiesis
30
Which dz are exeptions to the non-regenerative type thing..
> iron deficiency anaemia may -> non-regenerative in the long term > immune mediated attack of RBC precursors no the mature cells -> non-regenerative
31
Why is melena particularly bad?
- LOSS of iron (cf. haemothorax etc. where RBC will be recycled)
32
Main 6 questions to ask wrt anaemia?
- mild mod severe? - regenerative/non? - macro/microcytic? - hypo/normochromic? - specific morphology changes? - does the sample give you the answer?
33
What is polycythaemia?
= erythrocytosis - ^ HCT, RBC count and Hbg > may be spurious or relative - dehydration (volume contraction) most common - RBC redistribution (splenic contraction) esp in horses
34
Causes and subgroups of absolute erythrocytosis?
``` > 1* (polycythemia vera) neoplasia [ in humans all cell lines, in animals RBC only] - myeloproliferative disorder of erythroid stem cells - EPO level normal/decreased - PO2 normal > 2* (appropriate or innaropriate - chronic hypoxia - EPO secreting tumours - EPO level raised ```
35
Hyperthyroid cats have ^ RBC - is this pathological?
- technically pathological but normal for the physiological state they are in (higher metabolic rates = higher oxygen demand)
36
What should be submitted alongside EDTA sample? How should this be stored??
Fresh blood smear - store blood in fridge until analysis (slows changes) - store smears at room temperature (NOT IN FRIDGE)