Brainscape's Knowledge GenomeTM

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


See full index

2.2 Haematology > Lab Information I forget > Flashcards

Lab Information I forget Flashcards

1
Q

Define MCV and how is it calculated

A

Mean corpuscular volume
The average volume of a red blood cell expressed in femtolitres

Haematocrit x10/RBC

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

What is MCH and how is it calculated

A

Mean corpuscular haemoglobin
The average weight of haemoglobin per red blood cells

Hb/RBC

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

What is MCHC and how is it calculated?

A

Mean corpuscular haemoglobin concentration
The average Hb in a given volume of blood in grams/litre

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

What is MCHC and how is it calculated?

A

Mean corpuscular haemoglobin concentration
The average Hb in a given volume of blood in grams/litre

Hb x 100/Hct%

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

How do we measure haemoglobin

A

Drabkins method/cyanmethaemoglobin method -> red colour spectrophotometry

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

Define haematocrit

A

A measurement of the proportion of blood that is made up of red cells

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

What causes microcytic and hypochromic rbcs

A

Iron deficiency
Thalassaemia

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

What is the Wright Stain

A

A polychromatic stain consisting of buffered solutions of methylene blue and eosin

Type of Romanowsky stain

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

What is a howell jolly body

A

DNA remnant

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

What is basophilic stiplling

A

Denatured RNA

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

What is basophilic stiplling

A

Denatured RNA

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

What are siderotic granules

A

Iron

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

What are heinz bodies

A

Oxidised denatured Hb

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

What is Turks solution

A

Stain used when counting WBC using a haemocytometer

Stain contains gentian violet and 6% acetic acid, gentian blue stains wbcs while acetic acid lysis rbcs

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

What is the romanowksy stain

A

A series of blue/red stains where the blue binds to acidic substances and the red binds to neutral or basic substances

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

What anaemias will increase reticulocytes
(5)

A

Thalassaemia
Pernicious anaemia after treatment
Iron deficiency anaemia after treatment
Haemolytic anaemias -> spherocytosis
Sideroblastic anaemia

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

What conditions will decrease reticulocyte counts

A

Aplastic anaemia (no new cells)
Untreated pernicious anaemia
Megaloblastic anaemia
Untreated iron deficiency anaemia
Anaemia of chronic infection
Chemotherapy

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

How do we investigate hereditary persistance of HbF

A

The Kleihaeuer Betke test

acid elutes HbA

HbF stains dark pink

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

What primary techniques are used to investigate haemoglobinopathies

A

HPLC

Isolectric focusing IEF

Hb electrophoresis

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

What secondary techniques are used to investigate Haemoglobinopathies

A

Hb electrophoresis

HPLC

Sickle solubility test

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

What is the principle behind HPLC

A

Different variants have different retention times

Hb is absorbed into column and eluted by means of a gradient of increasing ionic strength

Exchange column contains small spheres of silica which are modified to be weakly cationic

An anticoagulated specimen is lysed and diluted in buffer and injected into column

Hb is absorbed into column and eluted by means of a gradient of increasing ionic strength

Eluate passes through a photometer which measures changes in absorbance

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

What is the principle behind Hb electrophoresis

A

HBE utilises the charged properties of normal Hb and its variants to replicate characteristic mobility patterns on both alkaline and acidic gels

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

What is the principle of the sickle solubility test

A

HbS is insoluble in the deoxygenated state in a high molarity phosphate buffer (sodium hydrosulfite)

The crystals that form refract light and cause the solution to be turbid, can’t see through

24
Q

Thin blood film

A

Stained with Giemsa stain at pH 7.2

Used to determine % parasitaemia count

Used to determine species of parasite

Used to note the different stages of development seen

25
Q

Thick blood film

A

Stained with fields stain

Used to detect the presence of the parasite

Useful in low grade parasitaemias

26
Q

Sensitivity

A

A tests ability to determine the patient cases correctly

27
Q

Sensitivity

A

A tests ability to determine the patient cases correctly

True positive/(true positive + false negative)

28
Q

Specificity

A

A test’s ability to determine the healthy cases correctly

True negative/(true negative + false positive)

29
Q

Five main stages to the development of a granulocyte

A

Myeloblast

Pro-myelocyte

myelocyte

Meta-myelocyte

Granulocyte

30
Q

Precision

A

How well a series of measurements agree with each other

It is the closeness of agreement between independent test results obtained under stipulated conditions

31
Q

Accuracy

A

How well a measurement agrees with an accepted value

It is the closeness of the agreement between the result of a measurement and a true value of the measurement

32
Q

Deviation index

A

is a statistical tool used to assess the accuracy and precision of laboratory test results. It helps evaluate how closely the measured values obtained in the laboratory align with the expected or target values.

1 or lower is really goos

1-2 is satisfactory
2-3 is borderline
3 may indicate a problem

33
Q

Coefficient of varation

A

The coefficient of variation (CV) is a statistical measure used to assess the relative variability or dispersion of a dataset in relation to its mean. It is expressed as a percentage and provides a standardized measure of dispersion that allows for comparison between datasets with different means

A measure of precision

CV = (Standard Deviation / Mean) * 100

below 10% indicates results are near the mean and are precise

34
Q

Mean

A

Average of the values

35
Q

Standard deviation

A

a measure of the dispersion or spread of values in a dataset. It quantifies how much the individual data points deviate from the mean

A higher standard deviation indicates a greater spread or variability of values in the dataset

36
Q

What four tests are carried out for iron deficiency anaemia

A

Serum iron
Transferrin (TIBC)
% transferrin saturation
Serum ferritin

37
Q

How is %transferrin determined

A

Serum iron/TIBC x1000

38
Q

How is %transferrin determined

A

Serum iron/TIBC x100

39
Q

What are the clinical findings of iron deficiency anaemia?

A

Decreased:
- Haemoglobin
- MCV
- MCH
- Reticulocytes
- Ferritin
- serum iron
- 15%> transferrin %

Hypochromic, microcytic rbcs

40
Q

Clinical findings of Thalassaemia

A

Reduced
- Haemoglobin
- MCV
- MCH
- haptoglobin

Increased
- Reticulocytes
- Lactate dehydrogenase
- Bilirubin

Hypochromic
Microcytic
Target cells
Anisopoikilocytosis
Pappenheimer bodies
Basophilic stipppling
Inclusion bodies (HbH only)

41
Q

What tests should be carried out for B thalassaemia

A

HPLC -> low HbA, high HbF and HbA2
Gel electrophoresis
Family studies
DNA analysis

42
Q

What tests should be carried out for a Thalassaemia

A

H prep
HPLC -> HbH peak and Hb Barts
Gel electrophoresis
Family studies
DNA analysis

43
Q

How is a H prep carried out

A

Incubation with brilliant Cresyl blue

HbH will precipitate

Results in appearance of multiple discrete inclusions - golf ball apoearance

44
Q

Clinical findings of megaloblastic anaemia

A

Increased:
- MCV
- MCH
- Lactate dehydrogenase and bilirubin

MCHC (normal or low)

Reduced:
- WCC
- platelets
- haptoglobin
- reticulocytes

Oval macrocytes
Hypersegmented neutrophils

45
Q

Stages of granulocyte

A

Haematopoietic stem cell follows the myeloid pathway -> develops into a CFU-GEMM

CFU-GEMM into CF-GM

Depending on stimulus GF-GM will develop into a different granulocyte:
- G-CSF = neutrophil
- IL-5 = eosinophil
- SCF = basophil (can become mast cells in tissues)

Neut CFU -> myeloblast, promyeloblast, myeloblast, myelocyte, metamyelocyte, mature neutrophil

Grow factor inhibits apoptosis and promotes differentiation

46
Q

Clinical findings of ALL

A

High lymphoblasts greater than 20%
Low red cell count
Low haemoglobin
Low platelet count
Hypercellularity in bone marrow

Philadelphia chromosome - BCR-ABL1

47
Q

Clinical findings of AML

A

Varying degrees of myeloblast increase

Auer rods

48
Q

Clinical findings of CLL

A

Hair cells
Smudge cells
Increased reticulocytes
Haemoglobin decreased
Neutropenia
B Cells expressing CD19, CD5, CD23, CD20

49
Q

Clinical findings of CML

A

Red blood cell count down
Little to no platelets
White blood cell count up
Blast cells

50
Q

Clinical findings of HS

A

Spherocytes
Anaemia + splenomegaly + jaundice depending on severity

Increased:
- MCHC
- reticulocytes (not always)(recovery phase)
- bilirubin

Normal or reduced MCV

51
Q

What do we need to rule out for HS

A

EMA
Autoantibodies
Autoimmune haemolytic anaemia
Irregular maternal IgG antibodies

52
Q

What tests are carried out for HS

A

EMA flow cytometry
SDS-page
osmotic fragility test

53
Q

Clinical findings for G6PD

A

Decreased:
- haemoglobin
- MCV
- haptoglobin

Increased
- NRBCs
- reticulocytes
- LDH
- bilirubin

MCH normal
Bite cells
Heinz bodies

54
Q

What tests are carried out for G6PD

A

Heinz body stains
MetHb reduction
Fluorescence spot screening
DNA analysis

55
Q

Explain oxygen dissociation curve

A

The oxygen dissociation curve is a curve that plots the proportion of Hb in its oxygen saturated form on the vertical axis against the prevailing oxygen tension on the horizontal axis. It’s important for understanding how our blood carries and releases oxygen. It relates oxygen saturation (SO2) and partial pressure of oxygen in the blood (PO2). It is determined by haemoglobin affinity for oxygen i.e. how readily haemoglobin acquires and releases oxygen molecules into the fluid that surrounds it

2.2 Haematology (38 decks)

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