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Med T IOD > Haematology > Flashcards

Haematology Flashcards

1
Q

Macrocytic and Microcytic Anaemia

What is Anaemia?

*LOB: Define Anaemia

A

Anaemia is a haemoglobin (Hb) level two standard deviations below the mean for the age and sex of the patient

This is often the presenting sign of an underlying disorder rather than a condition itsself

develops when the rate of RBC production decreases and/or the rate of RBC loss increases.

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2
Q

Macrocytic and Microcytic Anaemia

What are the types of anaemia?

*LOB: Give a classification for anaemia

A

Defined using the MCV

MCV < 80 fL = Microcytic

MCV 80-100 fL = Normocytic

MCV > 100 fL = Macrocytic

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3
Q

Macrocytic and Microcytic Anaemia

What are the subtypes of anaemia?

*LOB: Give a classification for anaemia

A

MCV 80-100 fL = Normocytic

If reticulocyte > 2% “Hyperproliferative” Normocytic Anaemia sign of blood loss/ haemolysis

If reticulocyte < 2% “Hypoporliferative” Normocytic Anaemia sign of decreased RBC production

MCV > 100 fL = Macrocytic
If megaloblastic deficiency of DNA production/ maturation
If non-megaloblastic all other error, hypersegmented neutrophils are absent

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4
Q

Macrocytic and Microcytic Anaemia

Presentation of Anaemia

*LOB: Describe the symptoms and signs of anaemia

A
  • fatigue
  • shortness of breath
  • dizziness and light-headedness
  • pale skin colour
  • a sore tongue
  • hair loss
  • unusual cravings for non-food substances, such as dirt, ice, paint, or clay. This is called pica
  • thin nails that might start to curve backwards (called spoon nails)
  • poor muscle performance (for example, you might not be able to exercise as long as usual)
  • restless leg syndrome. This means you have an irresistible urge to move your legs to relieve uncomfortable sensations, such as itching or a ‘crawling’ feeling.
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5
Q

Macrocytic and Microcytic Anaemia

What are the lab investigations for anaemia?

*LOB: Lab features and investigations of microcytic anaemia

A

FBC
* Hb conc of Haemoglobin (g/L)
* WBC
* Platelet
* MCV Average size of RBC
* Neutrophil
* Monocyte
* Eosinophil
* Basophil
* HCT %of blood volume as RBC
* RBC
* MCH Average haemoglobin content of RBC
* MCHC calculated measure of haemoglobin concentration in given red blood cells
* RDW Range of deviation around RBC size
* Lymphocyte count
* ? ESR

Blood film / smear Reticulocyte count

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6
Q

Macrocytic and Microcytic Anaemia

What does a blood film show?

*LOB: Lab features and investigations of microcytic anaemia

A

Size Megaloblastic, Normoblastic, Microblastic
Shape Fragments, tear drop, spiculated, ovalocyte, spherocyte, eliptocyte, acanthocyte, codocyte
Colour pale, normal, polychromasia
Inclusions Howell-Jolly (RBC with spot = asplenia), nuclear remnants, malarial parasties, basophilic stippling (blue dot= lead poisoning, thalassaemia, infection)

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7
Q

Macrocytic and Microcytic Anaemia

Types of Anaemia

*LOB:Give a classification for anaemia

A

From low Hb and size of RBC

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8
Q

Macrocytic and Microcytic Anaemia

How does age affect Hb and MCV?

*LOB: Lab features and investigations of microcytic anaemia

A
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9
Q

Macrocytic and Microcytic Anaemia

Where is iron in the body?

*LOB: Discuss the investigation of iron deficiency anaemia

A

Iron is required for erythropoesis.

It is stable as ferric (+3) and Ferrous (+2) and often circulating in Hb

Storage in cells = Ferritin
Storage pigment (lysosome) = haemosidirin

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10
Q

Macrocytic and Microcytic Anaemia

Iron Metabolism Recap

*LOB: Discuss the investigation of iron deficiency anaemia

A
  • Absorbed from duodenum via enterocytes
  • Binds to transferritin
  • Transported to bone marrow to make RBC
  • Excess stored as ferritin
  • GI mucosal cells regulate uptake via ferroportin receptors
  • Hepcidin Hormone and Hepcidin receptor causes uptake
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11
Q

Macrocytic and Microcytic Anaemia

What is the effect of iron in erythropoetic activity?

*LOB: Discuss the investigation of iron deficiency anaemia

A

Normal Iron -> Normal EPO -> Normal Bone Marrow = NORMAL ERYHTROCYTE

Low Iron -> Excessive EPO -> Hyperactive bone marrow to compensate ->increased erythroblast and reticulocyte count

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12
Q

Macrocytic and Microcytic Anaemia

What is the effect of iron in erythropoetic activity?

*LOB: Discuss the investigation of iron deficiency anaemia

A

Normal Iron -> Normal EPO -> Normal Bone Marrow = NORMAL ERYHTROCYTE

Low Iron -> Excessive EPO -> Hyperactive bone marrow to compensate ->increased erythroblast and reticulocyte count

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13
Q

Macrocytic and Microcytic Anaemia

What are Iron studies?

*LOB: Discuss the investigation of iron deficiency anaemia

A

Serum iron can be low due to infection, this looks at overall iron and other factors to find other causes.

In Iron Deficiency

Serum Fe
Hugely variable during the day/ Low (normal)

Ferritin
Primary storage protein & providing reserve, Water soluble / Low (unless inflammation)

Transferrin Saturation
Ratio of serum iron and total iron bindingcapacity – revealing % of transferrin binding sites that have been occupied by iron / Low

Total Iron Binding Capacity
Measurement of the capacity of transferrin to bind iron
It is an indirect measurement of transferrin / High

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14
Q

Macrocytic and Microcytic Anaemia

Common causes of iron deficiency anaemia

*LOB: Describe the common causes of iron deficiency anaemia

A

NOT ENOUGH IN
Poor Diet
Malabsorption
Increased physiological needs

LOSING TOO MUCH
Blood loss
menstruation, GI tract loss, paraistes

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15
Q

Macrocytic and Microcytic Anaemia

Other causes of microcytic anaemia

*LOB: Discuss other causes microcytic anaemia

A

Remember TICS
Thalassaemia
Iron Deficiency
Chronic Disease
Sideroblastic Anaemia

Also Lead Poisoning but increasingly rare

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16
Q

Macrocytic and Microcytic Anaemia

common causes of macrocytic anaemia

*LOB: Describe the common causes of macrocytic anaemia

A

Megaloblastic : Low reticulocyte count
Vitamin B12/Folic acid deficiency
Drug-related
(interference with B12/FA metabolism)

Nonmegaloblastic
Alcoholism ++
Hypothyroidism
Liver disease
Myelodysplastic syndromes
Reticulocytosis (haemolysis)

Remember FAT RBC MC
F-Foetus
A-Alcohol Excess
T-Hypothyroidism
R-Reticulocytosis
B-B12 and Folate
C-Chronic Liver disease
M-Myeloproliferative disorder
C-Cytotoxic Drugs

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17
Q

Macrocytic and Microcytic Anaemia

Folate Deficiency and causes

*LOB: Describe the differences between vitamin B12 deficiency and folate deficiency with respect to underlying causes, time to development of the clinical deficiency state, and clinical manifestations

A

Folate essential for DNA synthesis (bases)

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18
Q

Macrocytic and Microcytic Anaemia

B12 Defiency and Causes

*LOB: Describe the differences between vitamin B12 deficiency and folate deficiency with respect to underlying causes, time to development of the clinical deficiency state, and clinical manifestations

A

Essential co-factor for methylation in DNA and cell metabolism
Intracellular conversion to 2 active coenzymes necessary
for the homeostasis of methylmalonic acid (MMA) and
homocysteine

Requires the presence of Intrinsic Factor for absorption in terminal ileum

IF made in Parietal Cells in stomach
Transcobalamin II and Transcobalamin I
transport vitB12 to tissues

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19
Q

Macrocytic and Microcytic Anaemia

Consequences of B12 Deficiency

*LOB: Describe the differences between vitamin B12 deficiency and folate deficiency with respect to underlying causes, time to development of the clinical deficiency state, and clinical manifestations

A

Brain: cognition, depression, psychosis
Neurology: myelopathy, sensory changes, ataxia, spasticity (Sub Acute Combined Degeneration of the Cord)
Infertility
Cardiac cardiomyopathy
Tongue: glossitis, taste impairment
Blood: Pancytopenia

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20
Q

Macrocytic and Microcytic Anaemia

Comapare B12 and Folate

*LOB: Describe the differences between vitamin B12 deficiency and folate deficiency with respect to underlying causes, time to development of the clinical deficiency state, and clinical manifestations

A
  • Dietary: B12 found in animal products, folate in leafy greens, legumes
  • B12 is absoprtion error driven, lack of IF
  • Folate is increased demand driven AND Malabsorption error
  • Drug B12 - metformin or NO, Folate - methotrexate, trimethorpim, anticonvulsants
  • Time B12 - years due to large hepatic store, Folate quickly as no reserve

Manifest both megaloblastic anaemia, neurological only B12 and glottitis and fatigue. In Folate risk of neural tube in foetus

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21
Q

Macrocytic and Microcytic Anaemia

Other macrocytic anaemia causes

*LOB: Discuss other causes macrocytic anaemia

A

Pernicious Anaemia
Autoimmune disorder
Lack of IF
Lack of
B12 absorption
Gastric Parietal cell antibodies
IF antibodies

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22
Q

Coagulation: Inherited and acquired Thrombotic disorders

What is Virchow’s Triad

*LOB: Identify the components of Virchow’s triad and their pathophysiologic contribution to thrombosis
s

A

Endothelial injury
Stasis
Blood components
* Platelets
* Coagulation factors
* Coagulation inhibitors
* Fibrinolytic factors

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23
Q

Coagulation: Inherited and acquired Thrombotic disorders

Acquired Risk for Thrombosis

*LOB: Identify the components of Virchow’s triad and their pathophysiologic contribution to thrombosis

A

Bed rest
Plaster Cast
Trauma
Sugrery
Malignancy
Oral Contraceptives
HRT
Antiphospholipid syndrome
Myeloproliferative disorders
Polycythema Vera
Central Venous Catheters
Age
Obesity

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24
Q

Coagulation: Inherited and acquired Thrombotic disorders

Inherited Risk for Thrombosis

*LOB: Identify the components of Virchow’s triad and their pathophysiologic contribution to thrombosis

A

Antithrombin deficiency
Protein C deficiency
Protein S deficiency
Factor V Leiden
Prothrombin 20210A
Dysfibrinogenemia
Factor XIII 34Val

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25
Q

Coagulation: Inherited and acquired Thrombotic disorders

Mixed Risk for Thrombosis

*LOB: Identify the components of Virchow’s triad and their pathophysiologic contribution to thrombosis

A

High Levels of Factor VIII
High Levels of factor IX
High levels of factor XI
High levels of fibrinogen
High levels of TAFI
Low levels of TFPI
APC resistance in the absence of FV:
Hyperhomocysteinemia
High levels of PCI (PAI-3)

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26
Q

Coagulation: Inherited and acquired Thrombotic disorders

Inherited thrombophilia

*LOB: Describe the main inherited and acquired haemostatic disorders and their clinical manifestations

A
  • Factor V Leiden
  • Prothrombin mutation
  • Protein C deficiency
  • Protein S deficiency
  • Antithrombin deficiency

Unlikely: High Factor VIII, Hyperhomocysteinaemia.

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27
Q

Coagulation: Inherited and acquired Thrombotic disorders

Antiphospholipid Syndrome

*LOB: Describe the main inherited and acquired haemostatic disorders and their clinical manifestations

A

Autoimmune disorder
* Antibodies
* B2 glycoprotein/Anti cardiolipin and Lupus anticoagulant
* Antibodies interact with Platelet factor IV
* Platelet activation
Clinical manifestations
Thrombosis
Arterial and Venous
Pregnancy complications

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28
Q

Coagulation: Inherited and acquired Thrombotic disorders

Thrombocytopenic thrombotic conditions

*LOB: Describe the main inherited and acquired haemostatic disorders and their clinical manifestations

A

Thrombocytopenia
* Neurological abnormalities
* MAHA
* Fever
* Renal failure
* Diagnosis
* ADAMTS13 assay

29
Q

Coagulation: Inherited and acquired Thrombotic disorders

Heparin Induced Thrombocytopenia

*LOB: Describe the main inherited and acquired haemostatic disorders and their clinical manifestations

A

In HIT, heparin binds to platelet factor 4 (PF4), forming a complex.
The immune system produces IgG antibodies against this complex, which bind to platelets.
These antibody-platelet complexes activate platelets, leading to both thrombocytopenia and thrombosis.

30
Q

Coagulation: Inherited and acquired Thrombotic disorders

Vaccine Induced Immune Thrombotic Thrombocytopenia

*LOB: Describe the main inherited and acquired haemostatic disorders and their clinical manifestations

A

VITT is a rare but serious condition associated with certain COVID-19 vaccines, particularly adenovirus-vectored vaccines (e.g., AstraZeneca, Johnson & Johnson)

31
Q

Coagulation: Inherited and acquired Thrombotic disorders

Inherited thrombophilia testing in lab

*LOB: Describe the main inherited and acquired haemostatic disorders and their clinical manifestations

A

Direct assays
* Protein C
* Protein S
* Antithrombin levels
* Mutation analysis for prothrombin gene mutation and factor V
Leiden

32
Q

Coagulation: Inherited and acquired Thrombotic disorders

Antiphospholipid Syndrome Investigation

*LOB: Describe the main inherited and acquired haemostatic disorders and their clinical manifestations

A

Lupus anticoagulant
* Detection of Anti cardiolipin
antibodies IgG and IgM
* HIT
* VITT
* TTP
* ADAMTS13 assay

33
Q

Coagulation: Inherited and acquired Thrombotic disorders

How does Heparin work?

A
34
Q

Bone Marrow Failure

What is bone marrow failure?

*LOB: Define bone marrow failure

A

insufficient amount of red blood cells, white blood cells or platelets

35
Q

Bone Marrow Failure

What is bone marrow failure?

*LOB: Define bone marrow failure

A

insufficient amount of red blood cells, white blood cells or platelets

36
Q

Bone Marrow Failure

Classifications of Bone Marrow Failure

*LOB: List the causes of the marrow failure

A

Inhertied / Single Lineage
Anaemia (Diamon- Blackfan)
Neutropenia (Congenital)
Thrombocytopenia (congenital amegakaryocytic and thromboctyopenia with absent radii-TAR)

Acquired / Single Lineage
Pure red cell plasma

Inherited / Pancytopaenia
Fanconi Anaemia
Dyskeratosis Congenita
Shwachman- Diamond Pearson

Acquired / Pancytopaenia
Aplastic Anaaemia
Bone marrow infiltration
Paroxysmal nocturnal haemoglobinuria

37
Q

Bone Marrow Failure

What is Diamond-Blackfan Anaemia

*LOB: List the causes of the marrow failure

A

inherited PRCA. Skeletal abnormalities [craniofacial, thumb &
upper limb, cardiac and urogential malformation, cleft palate, increased risk of leukaemia

PRCA- pure red cell aplasisa

38
Q

Bone Marrow Failure

What is Thrombocytopenia with absent radii

*LOB: List the causes of the marrow failure

A

low platelet count with no radius bone
associated with lactose intolerance cardiac and kidney problems

PRCA- pure red cell aplasisa

39
Q

Bone Marrow Failure

What is Fanconi Anaemia?

*LOB: List the causes of the marrow failure

A

pancytopaenia
short stature, endocrine problems, skin pigmentation, abnormalities of arms, eyes kidneys ears
Increased risk of cancer especially AML

PRCA- pure red cell aplasisa

40
Q

Bone Marrow Failure

What is Dyskeratosis congenita?

*LOB: List the causes of the marrow failure

A

skin pigmentation, nail dystrophy and oral leukoplakia with progressive BMF

PRCA- pure red cell aplasisa

41
Q

Bone Marrow Failure

What is Shwachman- Diamon Pearson

*LOB: List the causes of the marrow failure

A

predominantly neutropaenia
all 3 cell lines affected
exocrine pancreatic dysfunction. growth retardation

PRCA- pure red cell aplasisa

42
Q

Bone Marrow Failure

What is Shwachman- Diamon Pearson

*LOB: List the causes of the marrow failure

A

predominantly neutropaenia
all 3 cell lines affected
exocrine pancreatic dysfunction. growth retardation

PRCA- pure red cell aplasisa

43
Q

Bone Marrow Failure

What is Myeloplastic syndrome?

*LOB: List the causes of the marrow failure

A

abnormal cells in the BM which do not mature

44
Q

Bone Marrow Failure

What is paroxysmal nocturnal haemoglobinuria

*LOB: List the causes of the marrow failure

A

defective blood cells (RBC) very susceptible to destruction by the complement system
haemolysis
haemoglobinuria
bone marrow dysfunction and risk of life threatenin blood clots/

45
Q

Bone Marrow Failure

What is aplastic anaemia?

*LOB: List the causes of the marrow failure

A

Hypocellular bone marrow
no abnormal cells
no fibrosis

At least 2 of the following:
Hb < 100 g/L
Plt < 50x109/L
Neut < 1.5x109/L

46
Q

Bone Marrow Failure

What are the causes of AA?

*LOB: List the causes of the marrow failure

A

PREDICTABLE
Radiation, high dose chemotherapy - dose dependent
Predictable recovery course
IDIOSYNCRATIC
Drug induced – not dose related
Many small case reports – evidence unclear
Chloramphenicol
VIRAL
Hepatitis ( 5-10% of cases) ? EBV/CMV/ HIV
IDIOPATHIC
Majority of cases (60-70%)

47
Q

Bone Marrow Failure

Diagnosis of AA?

*LOB:Describe the symptoms and signs of bone marrow failure

A

FBC, blood film, retics, BM, Viral studies, LFTs

Exclude Paroxysmal Nocturnal Haemoglobinuria (PNH)
PIG-A gene mutation causing absence of GPI anchored proteins
Disregulated complement leads to intravascular haemolysis (thromboses)
NO depletion leads to smooth muscle contraction & vasoconstriction - pain

Exclude malignant hypocellular disease
Immunophenotyping, cytogenetics

Exclude late presentation of congenital forms
Chromosomal breakage analysis for Fanconi anaemia
X-rays, Autoimmune studies

48
Q

Bone Marrow Failure

What is Neutropaenic sepsis?

*LOB:Describe the principles of diagnosis and management of neutropaenic sepsis

A

medical emergency
life-threatening complication of chemotherapy
suspect in hypotensive tachycardia
WITHOUT FEVER

Neut < 1.0 x 10^9

49
Q

Bone Marrow Failure

How to treat Neutropaenic Sepsis

*LOB:Describe the principles of diagnosis and management of neutropaenic sepsis

A

Broad spectrum IV Abx without delay.
Intravenous fluids: To prevent or treat septic shock.

50
Q

Bone Marrow Failure

Symptoms and Signs of Bone Marrow Failure

*LOB: Describe the symptoms and signs of bone marrow failure

A

Specific to each cytopaenia but can be broadly:

Anemia (low red cells):
Fatigue
Pallor
Shortness of breath on exertion
Palpitations
Neutropenia (low white cells):
Frequent infections
Fever
Oral ulcers
Thrombocytopenia (low platelets):
Easy bruising
Petechiae (small red spots on the skin)
Bleeding gums or nosebleeds
Menorrhagia (heavy periods)
General signs:
Pale skin
Signs of infection (fever, sepsis)
Signs of bleeding (bruising, petechiae, bleeding mucous membranes)

51
Q

Bone Marrow Failure

Main causes of failure

*LOB: Discuss the main causes of bone marrow failure

A

Aplastic anemia: Can be idiopathic, autoimmune, or secondary to drugs, radiation, or viral infections.
Myelodysplastic syndromes (MDS): These are clonal stem cell disorders where the bone marrow produces dysfunctional cells.
Leukemia: Infiltration of the bone marrow with leukemic blasts prevents normal hematopoiesis.
Chemotherapy or radiotherapy: These treatments destroy rapidly dividing cells, including those in the bone marrow.

52
Q

Haemoglobinopathies

What is haemolytic anaemia?

*LOB: Define haemolytic anaemia and discuss the main causes and mechanis

A

Increased peripheral destruction of RBCs

Bone marrow continues to produce cells

Increased consumption means BM has to work harder to compensate.

As the BM tries to keep up, the patient becomes anaemic
RBC destroyed > RBC produced

53
Q

Haemoglobinopathies

Categorical Causes of Haemolytic Anaemia

*LOB: Define haemolytic anaemia and discuss the main causes and mechanis

A

Inherited
present from birth
Immune
Antibody mediated
Extravascular
site of destruction is the
spleen and other RES
organs

Acquired
Develops de novo - ?why
Non-immune
RBC or environment
Intravascular
site of destruction is within the vascular space

54
Q

Haemoglobinopathies

Causes of Haemolytic Anaemia

*LOB: Define haemolytic anaemia and discuss the main causes and mechanis

A

Inherited
Sickle Cell (I&E)
Membrane disorder (hereditary spherocytosis) (E)
G6PD deficiency (I)

Acquired
Paroxysmal Nocturnal Haemoglobinuria (I)
Microangiopathic haemolysis (I) TTP, DIC
Valve Haemolysis (I)
Autoimmune- cold, warm, drug induced (I&E)
Alloimune- transfusion, HDFN (I)

(I- intravascular; E- Extravascular)

55
Q

Haemoglobinopathies

Investigation of Haemolytic Anaemia

*LOB:Describe the investigation and management of haemolytic anaemia

A

Haemolysis Screen

FBC: Normocytic anaemia
Blood film: Spherocytes or red cell fragments
Reticulocytes: Increased
LDH: Increased (due to cell turnover)
Bilirubin: Increased (unconjugated)
Haptoglobin: Decreased in intravascular haemolysis
DAT: Positive in some immune cases

(I- intravascular; E- Extravascular)

56
Q

Haemoglobinopathies

Differences in Investigation of Haemolytic Anaemia

*LOB:Describe the investigation and management of haemolytic anaemia

A
57
Q

Haemoglobinopathies

Warm AIHA

*LOB:Discuss the characteristics of autoimmune haemolytic anaemia (AIHA)

A

Usually IgG mediated: DAT +ve:
AutoAb binds to RBCs at 37 degrees,
Removed by RE macrophages
Part of RBC membrane lost: spherocyte
Destroyed in the spleen prematurely
Extravascular

50% idiopathic
Other associations – CLL, LPD, SLE , RA

58
Q

Haemoglobinopathies

Cold AIHA

*LOB:Discuss the characteristics of autoimmune haemolytic anaemia (AIHA)

A

Usually IgM mediated: Complement + DAT
Primary CHAD
Ab binds to RBCs at 40C, causes red cell agglutination on blood film, worse in the cold (transport sample in the warm)
Associated with acrocyanosis, Raynauds, intravascular haemolysis.
Often triggered by Mycoplasma pneumonia, EBV (Secondary CHAD)
May be associated with underlying LPDs.

Paroxysmal cold haemoglobinuria (PCH)
Donath-Landsteiner antibody – biphasic. Binds to RBCs at 370C and lyses them at 200C. Often triggered by viral infections.
(in exams tends to be a child playing outside, who comes in to a warm house…!)

59
Q

Haemoglobinopathies

Direct Antiglobulin Test (or Coombs Test)

*LOB:Discuss the characteristics of autoimmune haemolytic anaemia (AIHA)

A
60
Q

Haemoglobinopathies

Management of AIHA

*LOB:Discuss the characteristics of autoimmune haemolytic anaemia (AIHA)

A

Look for associated/ underlying conditions and treat
WARM
Steroids, blood as needed
Rituximab (anti-CD20), splenectomy
COLD
Keep warm, blood warmers
Occasionally chemotherapy if LPD

61
Q

Haemoglobinopathies

What is MAHA?

*LOB:Understand the principles of MAHA and TTP

A

MAHA: Microangiopathic haemolytic anaemia

Characterised by mechanical destruction (due to environment) of red blood cells and therefore fragments (schistocytes) on the blood film

Often associated thrombocytopenia
(Thrombotic Microangiopathy)

Predominantly an acquired intravascular haemolysis

62
Q

Haemoglobinopathies

What is TTP?

*LOB:Understand the principles of MAHA and TTP

A

Rare
Text book – pentad:
1. Fever 2. Renal failure 3. Confusion
4. Thrombocytopenia 5. MAHA on blood film

Low plts, low Hb, high bili, high LDH, high creat, +/-positive troponin

Microthrombi

Often idiopathic, but also due to:
HIV, pregnancy, drugs, congenital

63
Q

Haemoglobinopathies

Management of TTP

*LOB:Understand the principles of MAHA and TTP

A

Endothelial cell damage releases ultra large vWF multimers into the bloodstream which bind to vWF receptors on platelets, causing aggregation.
Reduction of ADAMTS 13 (normally proteolyses vWF multimers)
with associated IgG antibody against ADAMTS 13
ADAMTS 13 is vWF cleaving protease
Reduction leads to platelet aggregation
No antibody in congenital forms: VERY RARE

Treatment
Plasma exchange, high-dose steroids, blood, folic acid
Rituximab, RRT?
Aspirin and prophylactic LMWH when platelets recover

64
Q

Haemoglobinopathies

What is Haemoglobinopathies?

*LOB: Describe the diagnosis and management of sickle cell disease and thalassaemia

A

Caused by an abnormality in globin chain structure
They are caused by single gene disorders
The most common are the ‘Sickle Cell Diseases’
There are others such as congential dyserythropoietic anaemia (CDA)

65
Q

Haemoglobinopathies

What is Thalassaemia?

*LOB: Describe the diagnosis and management of sickle cell disease and thalassaemia

A

The thalassaemias are caused by absent or reduced production of the alpha or beta globin chains which form the normal adult haemoglobin HbA (⍺2β2).
Caused by mutations in regulatory genes
Might overlap with haemoglobinopathies: HbS/beta thalassaemia

66
Q

Haemoglobinopathies

What is Sickle Cell?

*LOB: Describe the diagnosis and management of sickle cell disease and thalassaemia

A

Point mutation in the beta globin gene on chromosome 11
Amino acid substitution (Adenine to thymine)
Causes glutamic acid being substituted by valine at position 6.

67
Q

Haemoglobinopathies

Newborn screening for Sickle Cell?

*LOB: Describe the diagnosis and management of sickle cell disease and thalassaemia

A
68
Q

Haemoglobinopathies

Pathophysiology of Sickle Cell?

*LOB: Describe the diagnosis and management of sickle cell disease and thalassaemia

A

Med T IOD (7 decks)

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