Week 231 - Anaemia Flashcards

1
Q

Week 231

Anaemia in Adult Males is considered as an Hb Value less than what?

A

<13.5g/dl

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

Week 231

Anaemia in Adult Females is considered as an Hb Value less than what?

A

Hb <11.5 g/dl

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

Week 231

What is an Erythrocyte?

A

This is a fully developed red blood cell.

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

Week 231

How many new Erythrocytes are made each day?

A

1012 New Erythrocytes

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

Week 231

What is the primary site of EPO synthesis?

A

The peritubular cells of the kidneys (Renal cortex).

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

Week 231

How is EPO production triggered?

A

EPO is not stored. Like most physiological cycles, it is a negative feedback cycle. The production of EPO is triggered by tissue hypoxia (oxygen tension in the tubules of the kidney).

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

Week 231

What is the major stimulant for EPO production?

A

Hypoxia

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

Week 231

Chronic renal disease/Bilateral nephrectomy will stop or reduce the production of which growth factor?

A

EPO

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

Week 231

A failure of production of EPO causes what type of Anaemia?

A

Normacytic anaemia. The red cells will be a normal shape and size, but there will be less of them.

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

Week 231

In cases of chronic haemolysis, as in thalassaemia, EPO production rises as a result of chronic hypoxia. What effect(s) does this have?

A

An increase in EPO eads to an increase in the numbers of erythrocytes (red blood cells), resulting in expansion and eventually fatty deposition within the bone marrow. In children, this can cause growth deformities like Frontal Bossing.

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

Week 231

When do reticulocyte counts rise?

A
  • Haemorrhage
  • Haemolytic anaemia
  • Treatment of a haemotinic deficiency
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Week 231

What is the ratio of reticulocyte to red blood cell count in a normal human being?

A

1:100 Reticulocyte:Red blood cell

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

Week 231

What is a pronormoblast?

A

This is the earliest stage of the erythrocyte, formed from stem cells. They have a large nucleus, and no haemoglobin.

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

Week 231

What are normoblasts?

A

A precursor to red blood cells. There is still a nucleus, but through the many variations of normoblasts, this gradually decreases. Eventually it is extruded from the cell and released into the blood.

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

Week 231

What % of the final Haemoglobin do reticulocytes contain?

A

25%

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

Week 231

What is anaemia of chronic disease?

A

Anaemia of chronic disease. Within any individual who lives with a chronic disease (eg rheumatoid arthritis),a complex interaction of
inflammatory cytokines interferes with the red cell lifecycle by
impairing iron metabolism and inhibiting red cell precursors.
The end result is a normocytic anaemia.

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

Week 231

If asked to “check the haemotinics”, what do you look at?

A

Iron

Vitamin B12

Folate

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

Week 231

Iron content is rate-limiting for erythropoiesis. So, in iron deficiency anaemia, the cells are ___. This is known as ______ ______.

A

The red cells are smaller in size This is known as microcytic anaemia.

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

Week 231

What is the term used to describe low haemoglobin?

A

Hypochromic

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

Week 231

Vitamin B12 and Folate are used for which two important processes?

A

DNA Synthesis and Cell Mitoses.

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

Week 231

A Vitamin B12 or a folate deficiency leads to what?

A

These are important for DNA production and cell mitosis. A Lack means that cell formation and production happens more slowly. It leads to the productino of magaloblasts (enlarged, misshapen cells)!

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

Week 231

How much Ferrous Iron is absorbed from the small intestine every day in a healthy adult?

A

1mg/day

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

Week 231

Which protein does Iron attach to in the serum, and what is its function?

A

The protein is called Transferrin. It binds to iron, and transports it to the bone marrow.

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

Week 231

Which receptors are increased in iron deficiency?

A

Soluble Transfferin receptors. sTfR.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Week 231 What is ferritin?
It is a storage compound. Stored in the liver.
26
Week 231 Where are dying red blood cells recycled?
The spleen. This is where iron is recycled into the plasma for future use.
27
Week 231 Describe the iron deficieny **PROFILE**.
* Serum Iron is **reduced** * Serum total iron binding capacity is **increased**. The body is working hard to bind any iron that is left. * Serum ferritin is **reduced** since iron stores are low. * Serum soluble transferrin receptors are **increased** since any iron in the system is being used up.
28
Week 231 Give causes of Vitamin B12 deficiency
* Pernicious anaemia * Inadequate intake * Poor absorbtion
29
Week 231 What is the leading cause of B12 deficiency?
Pernicious anaemia. * Igg autoantibodies target parietal cells, and its product (intrinsic factor IF) * This basically means that less B12-IF is absorbed in the terminal ileum. BAD TIMES.
30
Week 231 What are the four proteins of importance in red blood cells?
Spectrin Actin Protein 4.1 Ankyrin
31
Week 231 Defects in the structural proteins that form red blood cells can cause what?
These cells cannot withstand the shear forces of the microcirculation. Their shape changes (eg they become elliptical). These then get destroyed within the spleen by macrophages. **This is haemolytic anaemia**.
32
Week 231 Hereditary spherocytosis and elliptocytosis are examples of what?
**Haemolytic anaemia**. These are both due to defets in the Spectrin, one of four major protein components in the red blood cell.
33
Week 231 What is Thalassaemia?
There is a reduced rate of synthesis of either alpha or Beta globin chains. Within this group of inherited conditions, there may be both ineffective erythropoiesis, and haemolysis, leading to hypochromic (low iron) normacytic (normal size) anaemia.
34
Week 231 What is sickle-cell disease?
There is an inheritance of two abnormal Beta chains (HbSS). The abnormality is a point mutation. This causes insolubility in the cells deoxygenated state, and crystalisation within the red blood cell. This...leads to sickle cell deformity, and vascular occlusion. Most often seen in Afro-Carribean populations.
35
Week 231 What is 2,3 - diphosphoglycerate?
This sits in between beta chains in haemoglobin, and helps to offload oxygen.
36
Week 231 The change from foetal to adult haemoglobin occurs at 3-6 months. What is the difference between adult and foetal haemoglobin?
Foetal Haemoglobin has a **higher affinity** for oxygen than adult haemoglobin.
37
Week 231 In metabolic alkalosis, what happens to the oxygen dissociation curve?
With an increased pH, CO2 is decreased, and the curve shifts to the LEFT. This means there is a higher affinity for oxygen in the lungs, and it is "harder" to release oxgen to tissues. This also occurs with foetal haemoglobin.
38
Week 231 How is the oxygen dissociation curve affected in metabolic acidosis?
Decreased pH, raised concentration of 2,3-DPG H+ ions. Shift to the right. This means greater release of O2 into the tissues.
39
Week 231 What is the role of the reticuloendothelial system?
Simply? This cleans up dead and dying/out of date cells.
40
Week 231 What are haemolytic anaemias?
A group of anaemias that lead to a shorteneed life span of red cells.
41
Week 231 What is LDH, and why is it useful?
This is a nucleic enzyme, released on red cell destruction. It's measurable in a blood sample, and is a useful indicator of haemolysis.
42
Week 231 When investigating haemolysis, what three things do you assess?
1. Lactic acid dehydrogenase (LAD) 2. Reticulocyte count 3. Billirubin
43
Week 231 How does haemolysis cause Jaundice?
Excess uncojugated billirubin can occur from the breakdown of haem groups.
44
Week 231 What are the defining levels of Haemoglobin, for anaemia in Males and Females?
Males: 13.5 g/dl Females: 11.5 g/dl
45
Week 231 How is the total circulating haemoglobin concentration determined?
* The circulating plasma volume * The total circulating haemoglobin mass
46
Week 231 How may pregnancy or splenomegaly cause anaemia?
These can cause in increase in plasma volume, effectively reducing heaemoglobing concentration, though circulating levels may appear normal.
47
Week 231 What is the end result of anaemia?
Tissue hypoxia is the end result of reduced oxygen carrying capacity in the red blood cells.
48
Week 231 What are the two key compensatory mechanisms in place that act in response to tissue hypoxia from anaemia?
1. Cardiac compensation. This is the major adapter. Both Stroke volume and heart rate increase to bring about a subsequent increase in cardiac output. This can present as palpatations or heart murmurs. 2. Commonly, a generalised pallor is observed. This is generally due to a vasoconstriction, with redistribution of blood to key areas.
49
Week 231 Name some of the general clinical signs and symptoms of anaemia.
* Headaches * SOB * Palpitations * Confusion and symptoms of cardiac failure * Weakness and lethargy * Glossitis * Angular Stomitis * Koilonychia * Dysphasia/Pharayngeal web
50
Week 231 Name some causes of microcytic, hypochromic anaemia.
Iron Deficiency Thallasaemia Sideroblastic
51
Week 231 What causes Normocytic normochromic anaemia?
Haemolysis Chronic Disease Marrow infiltration
52
Week 231 What causes Macrocytic megaloblastic anaemia?
Folate deficiency B12 deficiency
53
Week 231 G6PD deficiency and hereditary spherocytosis cause what type of anaemia?
Haemolytic anaemias.
54
Week 231 A Microcytic RBC has a MCV of what?
An MCV of LESS than 80fl
55
Week 231 Is a macrocytic blood film an indicator of excess alcohol consumption or liver disease?
Yes it is!
56
Week 231 Name three conditions in which target cells are found in peripheral blood films.
1. Liver disease (obstructive jaundice) 2. Thalassaemia major 3. Sickle cell anaemia
57
Week 231 In which conditions do you observe fragmented RBC's on peripheral blood film?
DIC TTP BURNS Cardiac Valve (synthetic)
58
Week 231 In which conditions does peripheral blood film show tear drop poikilocytes?
* Myelofibrosis * Extramedullary haemopoiesis
59
Week 231 Ringed RBC's on peripheral blood film are a sign of which condition?
Malaria infection from P falciparum.
60
Week 231 Prickle type RBC's pn peripheral blood film are indicative of which condition?
Pyruvate Kinase deficiency
61
Week 231 What is the most COMMON cause of IRON DEFICIENT anaemia?
Blood Loss
62
Week 231 What is Beta-Thallasemia?
This is a microcytic hypochromic anaemia. It is one of the most common autosomal inerited disorders. Pathology is reduced beta globin production, from ineffective erythropoiesis and haemolysis.
63
Week 231 What is the fundamental difference between warm and cold autoimmune haemolytic anaemias?
* Warm is associated with production of IgG * Cold is associated with production of IgM
64
Week 231 What are the functions of the haemopoietic system?
* **Transport**: cells, oxygen, hormones, drugs * **Surveilence**: Cells, cytokines, proteins * **Temperature regulation**: Blood flow control
65
Week 231 What are the component parts of the haemopoietic system?
**Bone**: Scaffold (medulla protected by cortical bone) and cells (stroma) **Blood**: vessels (endothelium) and cells (circulating) **Lymph**: vessels and cells (circulating, nodes and extra lymphatic tissues,Spleen, Thymus
66
Week 231 The bone marrow produces which two elements of the haemopoietic system?
Cells, and stroma (connective tissue)
67
Week 231 What do plasma cells produce?
Immunoglobulins
68
Week 231 What are the sites of prenatal blood production?
* Yolk sac * spleen * bone marrow * Bone marrow
69
Week 231 What are the main sites of postnatal blood production?
* Tibia * Femur * Rib * Sternum * Vertebra and pelvis
70
Week 231 B and T lymphocytes, and Natural Killer cells are derived from which earlier cell?
Lymphoid stem cell
71
Week 231 Granulocyte monocyte progenitor cells produce which cell types?
* Monocyte * Neutrophils
72
Week 231 Erythroid progenitors produce which type of cell?
Red blood cell
73
Week 231 Megakaryocyte progenitor cells produce what?
Platelets
74
Week 231 In a patient with acute renal failure, which agents would use to ensure adequate production of red blod cells?
Erythropoietin stimulating agents (ESA) Monitor haemoglobin to find appropriate dose. Aim for increase of no more than 20g/l over 4 weeks
75
Week 231 What is Hydroxocobalamin?
IM injection suitable B12 supplement.
76
Week 231 What does stem cell factor cause?
An increase in haemopoietic stem cell reproduction.
77
Week 231 G-MCSF (Granulocyte-Monocyte Colony Stimulating Factor) - **Stimulates what**?
↑MPC (myeloid progenitor cell) differentiation into granulocyte & monocyte lineage
78
Week 230 Where is **Thrombopoietin** produced, and what is it's effect?
Produced by liver & kidneys & accelerates megakaryocyte → platelet splitting
79
Week 231 G-CSF - Granulocyte Colony Stimulating Factor - What does it do?
- Accelerates production & maturation of neutrophils (+ inhibits neutrophil apoptosis
80
week 231 Neutrophils take 12 days to produce - but how long do they spend in circulation?
Just 12 hours!
81
Week 231 A trephine is usec as part of which invasive investigatory procedure?
Bone marrow biopsy
82
Week 231 What (physiologically) hapens to cause Idiopathic Thrombocytopenic Purpura?
Autoantibodies opsonise platelets, causing their lysis in the spleen.
83
Week 231 Name two drugs that are known triggers for idiopathic thrombocytic purpura.
Heparin Quinine
84
Week 231 What wil the FBC show in Idiopathic Thrombocytopenic Purpura?
**Isolated thrombocytopaenia** (often a compensatory increase in megakaryocytes too).
85
Week 231 A 30 year old man with: * Fever * Petechiae/Purpura * Jaundice * Signs of Anaemia * Pallor * fatigue * Altered mental state, * seizures * focal pathologies * Haematuria ---\>Acute Renal Failure, * Hypertension IVX show: * Thrombocytopenia * Anaemia, RBC Fragments
  • Unconj Bilirubinaemia
  • ↑Urea
  • ↑Creatinine
  • I have given every possible symptom here -- so what does the poor fellow have?
    Thrombotic Thrombocytopenic Purpura
    86
    Week 231 WHat is the pathophysiology of thrombotic thrombocytopenic purpura?
    * von Willebrand Factor Multimers circulate in blood * Congenital form - Pts lack ADAMTS13 enzyme which cleaves vWF multimers * Acquired forms (more common) - Autoantibodies antagonise enzyme --\>Platelets clump & cause ‘white’thromboses in small vessels -Mostly platelets content, little fibrin/RBCs * Thromboses & deposition damages organs incl. kidneys, CNS * Adults predominantly affected
    87
    Week 231 What is the pathophysiology of Haemolytic Uraemic Syndrome?
    * Entero-haemorrhagic E-Coli 0157- Produces * shiga-like toxin which Causes platelet-agglutination & "white thromboses" in small vessels * Similar pathology to TTP * Young Children mostly affected, but does occur in adolescents & adults
    88
    Week 231 In severe B12 deficiency, IM injection of which drug (every 3 months) is used?
    **Hydroxocobalamin** (1mg 3xweekly for 2 weeks, maintenance dose 4xyr) Can cause; Rash, chills, and hypokalaemia
    89
    Week 231 Which important vitamin is required to convert folic acid into folate?
    Vitamin B12
    90
    Week 231 When is Folic acid given (OTHER THAN PREGNANCY)?
    In **megaloblastic anaemia**, and when **Methotrexate** is given (it reduces the side effects)
    91
    Week 231 Name **two iron chelators**, that can be used in cases of iron overload or iron poisoning.
    * Desferrioxamine - IV or subcut. IV for poisoning, SC for overload * Desferasirox - This is given ORALLY. Causes gut irritation, so take on empty stomach, and avoid other irritants like NSAIDS. ## Footnote **Hearing and visual disturbances occur with both**
    92
    Week 231 Name two **Erythropoiesis Stimulating Agents**.
    * **EPO Alpha and Beta**. These are recombinant forms used in renal failure and post-chemo. * **Darbepoietin/Mircera** - This are EPO receptor agonists, with longer half lives. * CAN CAUSE: Red cell Aplasia (Bone marrow not producing RBC's), hypertension and iron deficiency
    93