Outline Anaemia Flashcards
(95 cards)
1
Q
when dooes Anaemia happen
A
when there aren’t enough red blood cells or haemoglobin
2
Q
what is Erythropoietin
A
the key regulator of red blood cell development
3
Q
what is Paroxyimal nocturnal haemoglobinuria
A
a haemolytic anaemia primarily caused by reduced formation of C3-convertase
4
Q
what causes Anaemia
A
a reduced number of red blood cells in circulation, or a decreased amount of haemoglobin in the red blood cells
5
Q
results of anaemia
A
reduced levels of oxygen delivery to tissues
6
Q
true or false, Anaemia may be significant before a patient appears pale
A
true
7
Q
symptoms of anaemia
A
weakness, tiredness, inability to exercise and shortness of breath
In some cases, this can lead to confusion, thirst and loss of consciousness
8
Q
signs of anaemia
A
Pallor of the conjunctiva especially Tachycardia Glossitis b12 definicineny Dark urine in haemolytic anaemia Koilonychia
9
Q
symptoms of anaemia
A
decreased work capacity, fatigue, lethargy
weakness dizziness, palpitations
shortness of breath esp on exertion
tired all the time
in children decreased IQ poor concentration and sleepiness
rarely headaches tinnitus (hearing shit) and taste disturbance
10
Q
mor severe anaemia symptoms
A
jaundice spenomegaly hepatomegly angina cardiac failure fever
11
Q
: Aetiological classification the bone marrow
A
suppression
infiltration
12
Q
problems with iron
A
defincinecy at bone marrow
excess absorptions
ineffective incorporation into haem
13
Q
lack of vitamines
A
B6 and 12
Folic acid
14
Q
anaemia associated with disease in other organs
A
liver kidney reproductive organs connective tissue thyroid
15
Q
haemolysis
A
due to antibioltics
due to drugs
infections
16
Q
anaemia arising from gene mutation
A
haemoglobinopathy
membrane defects
enzyme defectts
17
Q
anaemia due to blood loss
A
haemorrhage
trauma eg RTA,stab
18
Q
Multipotential
A
Regulated by stem cell cytokines (e.g. SCF, IL-3 and TPO) and haematopoietic niches in the bone marrow
19
Q
Erythroid
A
Primarily regulated by erythropoietin (EPO) and interactions with macrophages
20
Q
steps from Multipotential
hematopoietic stem cell to Erythrocyte
A
From Multipotential hematopoietic stem cell
to Common myeloid progenitor
to Proerythroblast (Pronormblast)
to Basophilic erythroblast
to Polychromatic erythroblast
to Orthochromatic erythroblast (Normoblast)
to Polychromatic erythrocyte (Reticulocyte)
to Erythrocyte
21
Q
Conditions affecting specifically erythropoiesis in the bone marrow are described as
A
PRCA pure red cell aplasia (PRCA)
22
Q
Conditions affecting production of other cell types in addition to RBCs (white cells and platelets) is termed
A
pancytopenia
23
Q
what is the most common pure red cell aplasia
A
Diamond-Blackfan anaemia,
24
Q
what is the cause of Diamond-Blackfan anaemia
A
occurs due to reduced proliferation of erythroblasts. This is a rare condition, occurring in ~5 lives births/million.
25
how is acquired pure red cell aplasia classified
primary (idiopathic – where no clear cause can be identified)
secondary (acquired as a result to exposure to a pathogenic agents such as a drug or infection)
26
Anaemia from changes in the bone marrow congenial
Diamond-Blackfan syndrome, congenital dyserythropietic anaemia
27
Anaemia from changes in the bone Infections
```
viruses:pavovirus B19
Hepatitis B virus
Epstein Barr virus
Mumps
Cytomeglovirus
HIV
```
Bacteria:menigococcal
and staphylococcal species
28
Anaemia from changes in the bone marrow Malignancy
```
solid tumour (such as cancer of the thymus, stomach, breast, lung, thyroid and kidney)
Haematological tumours (leukaemias, lymphomas, myeloma, myelofibrosis, essential thrombocythemia, Waldenstrom macroglobulinaemia
```
29
Anaemia from changes in the bone marrow Autoimmune diseases
Systemic lupus erythematosus, rheumatoid arthritus and auto-immune haemolytic anaemia, sjogrens symptoms, autoantibodies to red cell progenitors, autoantibodies to Epo, T-cell mediated recognition of red cell progenitors
30
what does anaemia from changes in the bone marrow lead to aside from red cell aplasia
pancytopenia and aplastic anaemia
31
Anaemia from changes in the bone marrow other causes
drugs and chemicals (notably azathioprine, methotrexate, gold, chloramphenicol, recombinant human Epo and co-trimoxazole)
Pregnancy
Severe renal failure
32
what does Failure of HSCs to self-renew will eventually lead to
exhaustion and pancytopenia
33
Haemolytic anaemias are caused by
the premature destruction (reduced lifespan from ~120 days) of functional erythrocytes either by extrinsic or extrinsic mechanisms.
34
in Haemolytic anaemia, Anaemia will develop if
the bone marrow is unable to match the destruction of erythrocytes by production of new cells.
35
Erythrocyte destruction usually occurs through 2 broadly different reasons:
1. There is nothing fundamentally wrong with the erythrocyte, but they are destroyed by external pathological processes, such as drugs, toxins auto-antibodies or infection
2. There is something intrinsically wrong with the erythrocyte so it is destroyed. This can be due to damage, absence of certain enzymes or abnormal types of haemoglobin
36
what are alloantibodies made in response to
the immune recognition of foreign erythrocytes that have been introduced via a blood transfusion or due to pregnancy (following the mixing of maternal and foetal blood at delivery)
37
One example of Alloantibodies
is haemolytic disease of the newborn (HDN)
38
how does Haemolytic disease of the newborn happen in a fetus
HDN develops in a foetus, when the IgG molecules produced by the mother pass through the placenta. Among these antibodies are some which attack antigens on the red blood cells in the foetal circulation, breaking down and destroying the cells.
39
what happens when the haemolytic diseases of the newborn is moderate or severe
many erythroblasts (immature red blood cells) are present in the foetal blood.
40
consequences of haemolytic disease of the newborn
ranges from mild to very severe, and foetal death from heart failure can occur.
41
when are Autoantibodies are found
when a patients’ immune system produces antibodies that recognize their own erythrocytes as foreign and mediate their destruction
42
Idiopathic AIHA accounts for approximately how many cases.
50%
43
what are the most common causes Secondary AIHA can result from many other illnesses
include lymphoproliferative disorders (e.g., chronic lymphocytic leukaemia, lymphoma) and other autoimmune disorders (e.g., systemic lupus erythematosus, rheumatoid arthritis, scleroderma, crohn's disease, ulcerative colitis).
44
Drug-induced Auto-immune haemolytic anaemia are rare, which drugs are they caused by caused by?
a number of drugs, including α-methyldopa and penicillin
45
Explain, using what happens when the drugs causing Auto immune Haemolytic ananea bind to the macromolecules on the surface of the RBCs how one type of penicilin allergy forms
acts as an antigen. Antibodies are produced against the RBCs, which leads to complement activation. This is one type of "penicillin allergy".
46
Schisocytes and polychromasia
Fragments of erythrocytes and larger, blue-tinged reticulocytes
47
nucleated erythrocytes
Nucleated erythrocyte
48
Spherocytes
Some cells are very small and termed micro-spherocytes
49
Haemoglobinopathies
autosomal co-dominant genetic defects resulting in abnormal structure of one of the globin chains of the haemoglobin molecule
50
what is the most common Haemoglobinopathy
Sickle cell
51
how does sickle cell come about?
due to mutations in the beta-globin gene.
52
how does the abnormal shape of the sickle cell affect its role
affects their passage through the circulatory system, their ability to carry O2 and increased haemolysis
53
Sickle cell anaemia can cause what?
vaso-occlusive crises (vessel blockage) visceral sequestration crisis, aplastic and haemolytic crises
54
how many molecules of haemoglobin does the erythrocyte contain?
640 million haemoglobin molecules
55
where is haemgobin made
made in the erythrocyte cytoplasm
56
how is hameoglobin designed
designed to absorb O2 from areas of high O2 content (lungs) and release it where O2 levels are low (tissues)
57
what are the two parts of haemoglobin?
contain a protein part (globin) and a complex non-protein part (haem)
58
how many globin subtypes are there
4
59
which essential micronutrients are required for various steps in regulating erythrocyte function, especially for the metabolism of haem.
iron, vitamins B12 and B6 and folic acid
60
why can iron, vitamins B12 and B6 and folic ac deficiency lead to anaemia
These micronutrients are obtained in the diet so malnutrition is likely to cause different types of anaemia
61
how can An apparently adequate diet may still lead to disease
as essential micronutrients may fail to be absorbed due to abnormalities of the intestines (malabsorption)
62
how can lack of iron directly impacts the amount of O2 that can be transported to the tissues.
Each molecule of haemoglobin must have an atom of iron to which O2 can bind to in the lungs
63
what does the blood film look like in Iron-deficiency anaemia
Iron deficiency is characterised by hypochromic (pale) microcytes (small)
RBCs seem to be “empty” with a lack of staining in the centre of the cell
RBCs are also significantly smaller (compare the size of RBCs to the white blood cell in the normal film)
64
daily iron requirements of an infant
1mg
65
daily iron requirements of adolescent
2-3mg
66
daily iron requirements of a menstruating adolescent
3-4mg (loses 20-25mg per menstruation)
67
daily iron requirements of an adult
2-3mg (loses 20-25mg per menstruation)
68
daily iron requirements of a pregnant lady
3-4mg (500-1000mg req overall)
69
daily iron requirements of a lactating lady (this amenhoroea likely)
1.5-2.5mg (but also req to repopulate stores)
70
daily iron requirements of a post menopausal female
1mg
71
Intestinal factors contributing to reduced iron absorption in the stomach
```
Achlorydria
Gastric atrophy
gastritis
Alcoholism
Gastric Carcinoma
```
72
Intestinal factors contributing to reduced iron absorption
```
Duodentiis
Caeliacs
Ulceration
Crohns
Other inflamatory blowel dieases
Increaased Hepcidin Levels
```
73
Intestinal factors contributing to reduced iron absorption
resection of stomach or UGI and LGI tissue
74
Iron High content
```
Dark-green leafy vegetables
Iron-fortified cereals
Whole grains
Beans
Nuts
Meat
Apricots
Prunes
Raisins
Iron tablets
```
75
Makes absorption difficult
```
Tea and coffee
Calcium
Antacids
Proton pump inhibitors (PPIs)
Wholegrain cereals (phytic acid)
```
76
What is sideroblastic anemia charaterized by?
failure of iron to be incorporated into haem in the erythrocyte precursor cells.
77
There are various forms of sideroblastic anaemia that are the consequence of mutations or deletions of genes regulating the expression of key enzymes involved in haem synthesis. A consequence of the failure to incorporate iron into the correct areas what happens?
formation of iron-rich mitochondria which surround the nucleus of the erythrocyte precursor as granules. These cells are termed “sideroblasts
78
what is haem
a complex molecule synthesized in the cytoplasm and mitochondria of erythrocyte progenitor cells.
79
what are the key regulators of haem production
Vitamins B6 and B12/folate
80
Which is most common, B12 Folate or B6 difficenecy?
Isolated vitamin B6 deficiency is rare in the absence of drugs, particularly the anti-tuberculosis agent isoniazid. However, B12/folate deficiency is relatively common
81
B12 replacements
```
Meat
Salmon
Milk
Eggs
Fortified cereal replacement
Soy products
```
82
Causes of Vit B12 Folate deficincines ?
```
Malnutrition and Malabosroption
Poverty
Pregnancy
Drugs
Pernicious Anamia: deficincency of gastric intrinsic factor
Gastrectomy
Small bowel sprue
Fish tapeworm
antacids
bacterial overgrowth
pancreatitis
```
83
what is Vitamin B12/folate is essential for in erythrocyte proliferation
DNA synthesis
84
what do defienceies cause?
reduction in erythropoiesis
85
HB
RBC
MCV
HCT
MCH
MCHC
RDW
haemoglobin
red blood cells
mean corpuscular (cell) volume
haematocrit
mean corpuscular haemoglobin
MCH concentration
Red blood cell distribution width
86
3 causes of anaeomia
- Reduced production of erythrocytes
- Increased destruction of erythrocytes
- Reduced production/defective haemoglobin
87
what are the key componants iin the correct diagnosis of aneomia
Full blood counts combined with blood films and patient histories
88
what are the three groups we divide anamia into?
microcytic, normocytic and macrocytic
89
Macrocytic anaemia is caused by
Recticulocytis
B12 and Folic Acid Defincinecy
Liver disease
Hypothyroidism
90
High RBC Microcytic anaemia is caused by
Thalassemias alpha and beta or combo with other hamoglobin abnormalities
91
Normocytic anaemia is caused by
```
hemolytic anaemias
bone marrow disorders
hypersplenism
acute blood loss
anaemias of chronic dieease
```
92
MCV of macrocytic anaemia is
high
93
MCV of Microcytic anaemia is
low
94
MCV of Normocytic anaemia is
normal
95
Normal or low RBC Microcytic anaemia is caused by
Iron defincinecy anaemia
Lead poising
Aneamia of chronic inflammation
Sideroblastic ananmia
