Brainscape's Knowledge GenomeTM

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


See full index

Y3 Content > Haematology > Flashcards

Haematology Flashcards

1
Q

Define macrocytic anaemia.

A

Anaemia associated with a high MCV of erythrocytes (> 100 fl in adults).

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

What are the causes of macrocytic anaemia?

A

o Megaloblastic - deficiency of B12 or folate required for the conversion of deoxyuridate to thymidylate, DNA synthesis and nuclear maturation

  • Vitamin B12 Deficiency = reduced absorption (e.g. post-gastrectomy, pernicious anaemia, terminal ileal resection or disease), Reduced intake, Abnormal metabolism (congenital transcobalamin II deficiency)
  • Causes of Folate Deficiency = Reduced intake, Increased demand (pregnancy, lactation, malignancy, chronic inflammation), Reduced absorption, Jejunal disease (e.g. coeliac disease), Drugs (e.g. phenytoin)

o Drugs = Methotrexate (dihydrofolate reductase inhibitor), Hydroxyurea, Azathioprine, Zidovudine

o Non-Megaloblastic = Alcohol excess, Liver disease, Myelodysplasia, Multiple myeloma, Hypothyroidism, Haemolysis, Drugs (e.g. tyrosine kinase inhibitor)

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

What are presenting symptoms of macrocytic anaemia?

A

o Non-specific symptoms of anaemia = Tiredness, Lethargy, Dyspnoea

o Family history of autoimmune disease

o Previous GI surgery

o Symptoms of the CAUSE (e.g. weight loss, diarrhoea)

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

What are the clinical signs of macrocytic anaemia on examination?

A

o Signs of Anaemia = Pallor, Tachycardia, Breathlessness

o Signs of Pernicious Anaemia = Mild jaundice, Glossitis, Angular stomatitis, Weight loss

Signs of B12 Deficiency = Peripheral neuropathy, Ataxia, Subacute combined degeneration of the spinal cord, Optic atrophy, Dementia

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

What are the appropriate investigations for macrocytic anaemia?

A

o Bloods = FBC, (high MCV, low Hb), LFT s (high bilirubin (due to ineffective erythropoiesis or haemolysis)), ESR, TFT, Serum vitamin B12, Red cell folate, Serum protein electrophoresis

o Antibodies = Anti-parietal cell and anti-intrinsic factor antibodies

o Blood Film = Large erythrocytes, Megaloblasts, Hypersegmented neutrophil nuclei

o Schilling Test

o Bone Marrow Biopsy (rarely needed)

o Investigations for the cause

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

What is the management of macrocytic anaemia?

A

o Pernicious Anaemia = IM hydroxycobalamin for life

o B12 Deficiency = Oral B12 with intrinsic factor (if pernicious) - treated before folate

o Folate Deficiency = Oral folic acid

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

What are the possible complications of macrocytic anaemia?

A

o Pernicious anaemia = increased risk of gastric cancer

o Pregnancy -> folate deficiency increases the risk of neural tube defects

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

Define microcytic anaemia.

A

Anaemia associated with a low MCV (< 80 fl).

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

What are the causes of microcytic anaemia?

A

o Iron Deficiency (most common) = Blood loss, Reduced absorption (e.g. small bowel disease), Increased demands (e.g. growth, pregnancy), Reduced intake

o Anaemia of Chronic Disease

o Thalassemia

o Sideroblastic Anaemia (abnormality of haem synthesis) = Inherited or secondary (e.g. to alcohol, drugs)

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

What are the presenting symptoms of microcytic anaemia?

A

o Non-Specific = Tiredness, Lethargy, Malaise, Dyspnoea, Pallor, Exacerbation of ischaemic conditions (e.g. angina, intermittent claudication)

o Lead Poisoning (can cause microcytic anaemia) = Anorexia, Nausea/Vomiting, Abdominal pain, Constipation, Peripheral nerve lesions

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

What are the clinical signs of microcytic anaemia on examination?

A

o Signs of anaemia = Pallor, Brittle nails and hair, Koilonychia, Glossitis, Angular stomatitis

o Signs of thalassaemia

o Lead poisoning signs = Blue gumline, Peripheral nerve lesions (causing wrist or foot drop), Encephalopathy, Convulsions, Reduced consciousness

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

What are the appropriate investigations for microcytic anaemia?

A

o Bloods = FBC (low Hb, low MCV), Serum iron (low in iron deficiency), Total iron binding capacity (high in iron deficiency), Serum ferritin (low in iron deficiency), Serum lead

o Blood Film

  • Iron deficiency anaemia = Microcytic, Hypochromic, Anisocytosis, Poikilocytosis
  • Sideroblastic anaemia = Dimorphic blood film, Hypochromic microcytic cells

o Lead poisoning = Basophilic stippling

o Hb Electrophoresis = Checking for haemoglobin variants and thalassemia

o Sideroblastic Anaemia = Ring sideroblasts in the bone marrow

o No obvious cause of blood loss is identified = Upper GI endoscopy, Colonoscopy, Haematuria

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

What is the management plan for microcytic anaemia?

A

o Iron Deficiency = Oral iron supplements

o Sideroblastic Anaemia = Treat the cause - Pyridoxine used in inherited forms with blood transfusion and iron chelation considered if there is no response to other treatments

o Lead Poisoning = Remove the source, Dimercaprol, D-penicillinamine

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

What are the possible complications of microcytic anaemia?

A

o High-output cardiac failure

o Complications related to the cause

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

Define normocytic anaemia.

A

Anaemia with normal MCV (80-100 fl).

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

What are the causes of normocytic anaemia?

A

o Decreased production of normal-sized blood cells (e.g. anaemic of chronic disease, aplastic anaemia)

o Increased production of HbS (sickle cell disease)

o Increased destruction of red blood cells (e.g. haemolysis, post-haemorrhagic anaemia)

o Uncompensated increase in plasma volume (e.g. pregnancy, fluid overload)

o Vitamin B2 deficiency

o Vitamin B6 deficiency

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

Define aplastic anaemia.

A

Characterised by diminished haematopoietic precursors in the bone marrow and deficiency of all blood cell elements (pancytopaenia).

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

What are the causes of aplastic anaemia?

A

o Idiopathic (> 40%) = May be due to destruction or suppression of stem cells via autoimmune mechanisms

o Acquired = Drugs (e.g. chloramphenicol, sulphonamides, methotrexate), Chemicals (e.g. benzene, DDT), Radiation, Viral infection (e.g. parvovirus B19), Paroxysmal nocturnal haemoglobinuria

o Inherited = Fanconi’s anaemia (bone marrow failure), Dyskeratosis congenita (a rare, progressive bone marrow failure syndrome)

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

What are the presenting symptoms of aplastic anaemia?

A

o Can be both slow-onset (months) or rapid-onset (days)

o Anaemia Symptoms = Tiredness, Lethargy, Dyspnoea

o Thrombocytopaenia Symptoms = Easy bruising, Bleeding gums, Epistaxis

o Leukopaenia Symptoms = Increased frequency and severity of infections

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

What are the appropriate investigations for aplastic anaemia?

A

o Bloods = FBC (low Hb, low platelets, low WCC, normal MCV, low or absent reticulocytes)

o Blood Film = Exclude leukaemia (check for abnormal circulating white blood cells)

o Bone Marrow Trephine Biopsy

o Fanconi’s Anaemia = Check for presence of increased chromosomal breakage in lymphocytes cultures in the presence of DNA cross-linking agents

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

Define anti-phospholipid syndrome.

A

A disease characterised by the presence of antiphospholipid antibodies (APL) in the plasma, venous and arterial thrombosis, recurrent foetal loss and thrombocytopaenia.

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

What are the presenting symptoms of anti-phospholipid syndrome?

A

o Recurrent miscarriages

o History of = Arterial thromboses (stroke), Venous thromboses (DVT, PE)

o Headaches (migraine)

o Chorea

o Epilepsy

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

What are the clinical signs of anti-phospholipid syndrome on examination?

A

o Livedo reticularis = mottled reticulated vascular pattern that appears as a lace-like purplish discolouration of the skin

o Signs of SLE (e.g. malar rash, discoid lesions)

o Signs of valvular heart disease

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

What are the appropriate investigations for anti-phospholipid syndrome?

A

o Bloods = FBC (low platelets, ESR (usually normal), U&Es -(can get nephropathy), Clotting screen (high APTT)

o Antibodies = Presence of antiphospholipid antibodies may be demonstrated - ELISA testing for anticardiolipin antibodies, Lupus anticoagulant assays

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

What are the indications for blood transfusions?

A

o Major surgery (less than 50x103 per uL)

o Ocular and neurosurgery (less than 100x103 per uL)

o Surgery with active bleeding (less than 50x103 per uL)

o Stable, non-bleeding (less than 10x103 per uL)

o Stable, non-bleeding with temperature of 38 degrees (less than 20x103 per uL)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

What are the complications of blood transfusions?

A

o Acute kidney failure

o Anaemia

o Lung problems

o Shock

o Viral infections

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

Define haemolytic anaemia.

A

Premature erythrocyte breakdown causing shortened erythrocyte life span (< 120 days) with anaemia.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

What are the hereditary causes of haemolytic anaemia?

A

o Membrane Defects = Hereditary spherocytosis, Elliptocytosis

o Metabolic Defects = G6PD deficiency, Pyruvate kinase deficiency

o Haemoglobinopathies = Sickle cell disease, Thalassemia

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

What are the acquired causes of haemolytic anaemia?

A

o Autoimmune = Antibodies attach to erythrocytes causing intravascular and extravascular haemolysis

o Isoimmune = Transfusion reaction, Haemolytic disease of the newborn

o Drugs = Penicillin, Quinine

o Trauma = Microangiopathic haemolytic anaemia - e.g. haemolytic uraemic syndrome, DIC, malignant hypertension

o Infection = Malaria, Sepsis

o Paroxysmal nocturnal haemoglobinuria

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

What are the presenting symptoms of haemolytic anaemia?

A

o Jaundice

o Haematuria

o Anaemia

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

What are the clinical signs of haemolytic anaemia?

A

o Pallor

o Jaundice

o Hepatosplenomegaly

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

What are the appropriate investigations for haemolytic anaemia?

A

o Bloods = FBC (low Hb, high reticulocytes, high MCV), High unconjugated bilirubin, Low haptoglobin, U&Es, Folate

o Blood Film = Leucoerythroblastic, Macrocytosis, Nucleated erythrocytes or reticulocytes, Polychromasia, Spherocytes, Elliptocytes, Sickle cells, Schistocytes, Malarial parasites

o Urine = High urobilinogen, Haemoglobinuria, Haemosiderinuria

o Direct Coombs’ Test = Tests for autoimmune haemolytic anaemia and identifies erythrocytes coated with antibodies

o Osmotic fragility test or Spectrin mutation analysis = Identifies membrane abnormalities

o Ham’s Test = Lysis of erythrocytes in acidified serum in paroxysmal nocturnal haemoglobinuria

o Hb Electrophoresis or Enzyme Assays = To exclude other causes

o Bone Marrow Biopsy (rarely performed)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

Define haemolytic uraemic syndrome (HUS) and thrombotic thrombocytopaenic purpura (TTP).

A

Triad of microangiopathic haemolytic anaemia (MAHA), acute renal failure, thrombocytopaenia.

o 2 forms:

  • D+ = diarrhoea-associated form
  • D- = no prodromal illness identified
34
Q

What are the causes of HUS and TTP

A

o Infection = E coli, Shigella, Neuraminidase-producing infections, HIV

o Drugs = COCP, Ciclosporin, Mitomicin, 5-fluorouracil

o Others = Malignant hypertension, Malignancy, Pregnancy, SLE, Scleroderma

35
Q

What are the presenting symptoms of HUS and TTP?

A

o GI = Severe abdominal colic, Watery diarrhoea that becomes bloodstained

o General = Malaise, Fatigue, Nausea, Fever < 38 degrees (D+)

o Renal = Oliguria or anuria, Haematuria

36
Q

What are the clinical signs of HUS and TTP on examination?

A

o General = Pallor, Slight jaundice, Bruising, Generalise oedema, Hypertension, Retinopathy

o GI = Abdominal tenderness

o CNS Signs = Occurs in TTP, Weakness, Reduced vision, Fits, Reduced consciousness

37
Q

WHat are the appropriate investigations for HUS and TTP?

A

o FBC = Normocytic anaemia, High neutrophils, Very low platelets

o U&Es = High urea, High creatinine, High K+, Low Na+

o Clotting = Normal APTT and fibrinogen levels (abnormality may indicate DIC)

o LFTs = High unconjugated bilirubin, High LDH from haemolysis

o Blood cultures

o ABG = Low pH, Low bicarbonate, Low PaCO2, Normal anion gap

o Blood Film = Schistocytes, High reticulocytes and spherocytes

o Urine = 1+ g protein/24 hrs, Haematuria

o Stool Samples = MC&S

o Renal Biopsy = Can distinguish between D+ and D- HUS

38
Q

Define haemophilia.

A

o Bleeding diatheses resulting from an inherited deficiency of a clotting factor.

o 3 subtypes:

  • Haemophilia A (most common) = deficiency in factor 8
  • Haemophilia B = deficiency in factor 9
  • Haemophilia C = RARE - deficiency in factor 11
39
Q

What are the risk factors for haemophilia?

A

o X-linked so mainly seen in males

40
Q

What are the presenting symptoms of haemophilia?

A

o Symptoms usually begin in early childhood

o Swollen painful joints occurring spontaneously or with minimal trauma (haemarthroses)

o Painful bleeding into muscles

o Haematuria

o Excessive bruising or bleeding after surgery or trauma

o Female carriers are usually asymptomatic, but may experience excessive bleeding after trauma

Generally speaking, bleeding in haemophilia is DEEP (into muscles and joints)

41
Q

What are the clinical signs of haemophilia on examination?

A

o Multiple bruises

o Muscle haematomas

o Haemarthroses

o Joint deformity

o Nerve palsies (due to nerve compression by haematomas)

Signs of iron deficiency anaemia

42
Q

What are the appropriate investigations for haemophilia?

A

o Clotting screen (high APTT)

o Coagulation factor assays (low factor 8, 9 or 11 (depending on type of haemophilia))

o Other investigations may be performed if there are complications (e.g. arthroscopy)

43
Q

Define immune thrombocytopaenic purpura (ITP).

A

Syndrome characterised by immune destruction of platelets resulting in bruising or a bleeding tendency.

44
Q

What are the causes of ITP?

A

o Often Idiopathic

o Acute ITP is often seen after viral infection in children

o Chronic ITP is more common in adults

o Associated with: Infections (e.g. malaria, EBV, HIV), Autoimmune diseases (e.g. SLE, thyroid disease), Malignancies, Drugs (e.g. quinine)

o Autoantibodies are generated, which bind to platelet membrane proteins (e.g. GlpIIb/IIIa) resulting in thrombocytopaenia

45
Q

What are the presenting symptoms of ITP?

A

o Easy bruising

o Mucosal bleeding

o Menorrhagia

o Epistaxis

46
Q

What are the clinical signs of ITP on examination?

A

o Visible petechiae and bruises

o Signs of other illness (e.g. infections, wasting, splenomegaly) would suggest that other causes

47
Q

What are the appropriate investigations for ITP?

A

o Diagnosis of exclusion -> must exclude = Myelodysplasia, Acute leukaemia, Marrow infiltration

o Bloods = FBC (low platelets), Clotting screen (normal PT, APTT and fibrinogen)

o Autoantibodies (e.g. antiplatelet antibody)

o Blood Film = rule out pseudothrombocytopaenia (which is caused by platelets clumping together and giving falsely low counts)

o Bone Marrow = exclude other pathology

48
Q

Define myelodysplasia.

A

A series of haematological conditions characterised by chronic cytopaenia (anaemia, neutropaenia, thrombocytopaenia) and abnormal cellular maturation.

  • o There are FIVE subgroups:*
    • Refractory anaemia (RA)*
    • RA with ringed sideroblasts (RARS)*
    • RA with excess blasts (RAEB)*
    • Chronic myelomonocytic leukaemia (CMML)*
    • RAEB in transformation (RAEB-t)*
49
Q

What are the presenting symptoms of myelodysplasia?

A

o May be ASYMPTOMATIC and diagnosed on routine blood counts

o Symptoms of Bone Marrow Failure = Anaemia (fatigue, dizziness), Neutropaenia (recurrent infections), Thrombocytopaenia (easy bruising, epistaxis)

o Check risk factors = Occupational exposure to toxic chemicals, Prior chemotherapy or radiotherapy

50
Q

What are the clinical signs of myelodysplasia on examination?

A

o Signs of bone marrow failure

  • Anaemia (pallor, cardiac flow murmur)
  • Neutropaenia (infections)
  • Thrombocytopaenia (purpura or ecchymoses)
  • Gum hypertrophy

Lymphadenopathy

51
Q

What are the appropriate investigations for myelodysplasia?

A

Bloods = FBC (pancytopaenia)

o Blood Film = Normocytic or macrocytic red cells, Variable microcytic red cells in RARS, Low granulocytes, Granulocytes are not granulated

o Bone marrow aspire or biopsy = Hypercellularity, Ringed sideroblasts , Abnormal granulocyte precursors, 10% show marrow fibrosis

52
Q

Define myelofibrosis.

A

Disorder of haematopoietic stem cells characterised by progressive bone marrow fibrosis in association with extramedullary haematopoiesis and splenomegaly.

53
Q

What are the presenting symptoms of myelofibrosis?

A

o Asymptomatic = diagnosed after routine blood count

o Common = Weight loss, Anorexia, Fever, Night sweats, Pruritis

o Uncommon = LUQ pain, Indigestion (due to massive splenomegaly), Bleeding, Bone pain, Gout

54
Q

What are the clinical signs of myelofibrosis on examination?

A

o Splenomegaly

o Hepatomegaly (present in 50-60%)

55
Q

What are the appropriate investigations for myelofibrosis?

A

o Bloods = FBC (initially variable Hb, WCC and platelets but later anaemia, leukopaenia, thrombocytopaenia), LFTs (abnormal)

o Blood Film = Leucoerythroblastic changes (red and white cell precursors in the peripheral blood), ‘Tear drop’ poikilocytes

o Bone Marrow Aspirate or Biopsy = Aspiration usually unsuccessful - ‘dry tap’ (due to fibrosis) but trephine biopsy shows fibrotic hypercellular marrow, with dense reticulin fibres on silver staining

56
Q

Define polycythaemia.

A

An increase in haemoglobin concentration above the upper limit of normal for a person’s age and sex.

o Classified into:

  • Relative Polycythaemia = normal red cell mass but low plasma volume
  • Absolute (True) Polycythaemia = increased red cell mass
57
Q

What are the causes of polycythaemia?

A

o Polycythaemia Rubra Vera = Genetics (mutations in JAK2 tyrosine kinase)

o Secondary Polycythaemia

  • Appropriate increase in erythropoietin = Chronic hypoxia (e.g. chronic lung disease, living at high altitude)
  • Inappropriate increase in erythropoietin = Renal (carcinoma, cysts, hydronephrosis), Hepatocellular carcinoma, Fibroids, Cerebellar haemangioblastoma, Erythropoietin doping

o Relative Polycythaemia = Dehydration (e.g. diuretics, burns, enteropathy), Gaisbock’s syndrome (occurs in young male smokers with hypertension, which results in a decrease in plasma volume and an apparent increase in red cell count)

58
Q

What are the presenting symtpoms of polycythaemia?

A

o Headaches

o Dyspnoea

o Tinnitus

o Blurred vision

o Pruritis after hot bath

o Night sweats

o Thrombosis (DVT, stroke)

o Pain from peptic ulcer disease

o Angina

o Gout

o Choreiform movements

59
Q

What are the signs of polycythaemia on examination?

A

o Plethoric complexion = Red, ruddy skin

o Scratch marks from itching

o Conjunctival suffusion (redness of the conjunctiva)

o Retinal venous engorgement

o Hypertension

o Splenomegaly (in 75% of cases)

o Signs of underlying aetiology in secondary polycythaemia

60
Q

What are the appropriate investigations for polycythaemia?

A

o Required for Diagnosis = FBC - High Hb, High haematocrit, Low MCV

o Isotope Dilution Techniques = allows confirmation of plasma volume and red cell mass to distinguish between relative and absolute polycythaemia

o Polycythaemia Rubra Vera = High WCC, High platelets, Low serum EPO, JAK2 mutation, Bone marrow trephine and biopsy shows erythroid hyperplasia and raised megakaryocytes

o Secondary Polycythaemia = High serum EPO, Exclude chronic lung disease/hypoxia, Check for EPO-secreting tumours

61
Q

Define sickle cell disease.

A

A chronic condition with sickling of red blood cells caused by inheritance of haemoglobin S (HbS).

o Sickle Cell Anaemia = Homozygous HbS

o Sickle Cell Trait = Carrier of one copy of HbS

o Sickle Cell Disease = includes compound heterozygosity for HbS and:

  • HbC (abnormal haemoglobin in which glutamic acid is replaced by lysine at the 6th position in the beta-globin chain)
  • Beta-thalassemia
62
Q

What other factors can cause red blood cell sickling?

A

o Infection

o Dehydration

o Hypoxia

o Acidosis

63
Q

What are the presenting symptoms of sickle cell disease?

A

o Symptoms secondary to vaso-occlusion or infarction

  • Autosplenectomy = increased risk of infections with encapsulated organisms
  • Abdominal Pain
  • Bones = painful crises affect small bones of the hands and feet causing dactylitis in children and ribs, spine, pelvis and long bones in adults
  • Myalgia and Arthralgia
  • CNS = fits and strokes
  • Retina = visual loss (proliferative retinopathy)

o Symptoms of sequestration crisis = occur due to pooling of red cells in various organs (mainly the spleen)

  • Liver = exacerbation of anaemia
  • Lungs = acute chest syndrome
  • Breathlessness
  • Cough
  • Pain

Fever

Corpora cavernosa

Persistent painful erection (priapism)

Impotence

64
Q

What are the clinical signs of sickle cell disease on examination?

A

o Signs secondary to vaso-occlusion, ischaemia or infarction

  • Bone = joint or muscle tenderness or swelling (due to avascular necrosis)
  • Short digits
  • Retina = cotton wool spots due to retinal ischaemia

o Signs secondary to sequestration crisis

  • Organomegaly - spleen is enlargedin early disease
  • Priapism

o Signs of anaemia

65
Q

What are the appropriate investigations for sickle cell disease?

A

o Bloods = FBC (low Hb, reticulocytes - high in haemolytic crises but low in aplastic crises), U&Es

o Blood Film = Sickle cells, Anisocytosis (variation in size of red cells), Features of Hyposplenism (target cells, Howell-Jolly bodies)

o Sickle Solubility Test = Dithionate is added to the blood - in sickle cell disease you get increased turbidity

o Haemoglobin Electrophoresis = Shows HbS, Absence of HbA (if homozygous HbS), High HbF

o Hip X-Ray = Femoral head is a common site of avascular necrosis

o MRI or CT Head - if there are neurological complications

66
Q

What is the management plan for sickle cell disease - painful crisis?

A

o Oxygen

o IV Fluids

o Strong analgesia (IV opiates)

o Antibiotics

67
Q

What is the management plan for sickle cell disease?

A

o Infection Prophylaxis = penicillin V and regular vaccinations (particularly against capsulated bacteria e.g. pneumococcus)

o Folic Acid = if severe haemolysis or in pregnancy

o Hydroxyurea/Hydroxycarbamide = increases HbF levels and therefore reduces the frequency and duration of sickle cell crisis

o Red Cell Transfusion = severe anaemia or repeated transfusions (with iron chelators) may be required in patients suffering from repeated crises

o Advice = avoid precipitating factors, good hygiene and nutrition, genetic counselling, prenatal screening

o Surgical = bone marrow transplantation, joint replacement in cases with avascular necrosis

68
Q

What are the possible complications of sickle cell disease?

A

o Aplastic crises = Infection with Parvovirus B19 can lead to a temporary cessation of erythropoiesis -> RCC plummets in sickle cell patients because their RBCs have a shortened life span and can’t tolerate a cessation of erythropoiesis)

o Haemolytic crises

o Pigment gallstones

o Cholecystitis

o Renal papillary necrosis

o Leg ulcers

o Cardiomyopathy

o Death (usually around 50) - infection in children and pulmonary or neurological complications in adults

69
Q

Define thalassaemia.

A

A group of genetic disorders characterised by reduced globin chain synthesis.

  • Alpha thalassaemia
  • Beta thalassaemia major = no beta-chain synthesis
  • Beta thalassaemia intermedia = mild defect in beta-chain synthesis
  • Beta thalassaemia trait
70
Q

What are the presenting symptoms of beta thalassaemia?

A

o Presenting at 3-6 months - when the change from HbF to HbA takes place

o Anaemia

o Failure to thrive

o Prone to infection

71
Q

What are the presenting symptoms of alpha or beta thalassaemia trait?

A

o Asymptomatic

o Detected during routine blood tests or due to family history

72
Q

What are the clinical signs of beta thalassaemia on examination?

A

o Pallor

o Malaise

o Dyspnoea

o Mild jaundice

o Frontal bossing

o Thalassaemia facies (facial features caused by marrow hyperplasia)

o Hepatosplenomegaly (due to erythrocyte pooling and extramedullary haematopoiesis)

o Patients with beta-thalassemia intermedia may also have these signs

73
Q

What are the appropriate investigations for thalassaemia?

A

o Bloods = FBC (low Hb, low MCV, low MCH)

o Blood Film = hypochromic microcytic anaemia, target cells, nucleated red cells, high reticulocyte count

o Hb Electrophoresis = Absent or reduced HbA, high HbF

o Bone Marrow = hypercellular, erythroid hyperplasia

o Genetic Testing (rarely used)

o Skull X-Ray = ‘Hair on end’ appearance in beta thalassemia major - caused by expansion of marrow into the cortex

74
Q

What are the causes of B12 deficiency?

A

o Pernicious anaemia = lack of intrinsic factor

o Gastric = gastrectomy, atrophic gastritis

o Inadequate intake - vegan

o Intestinal = malabsorption, ileal resection, Crohn’s, tropical sprue

o Drugs = colchicine, metformin

75
Q

What are the presenting symptoms of B12 deficiency?

A

o Typical anaemia symptoms = Fatigue, Lethargy, Dyspnoea, Faintness, Palpitations, Headache

o Neurological Symptoms = Paraesthesia, Numbness, Cognitive changes, Visual disturbances

76
Q

What are the clinical signs of B12 deficiency on examination?

A

o Typical anaemia = Pallor, Glossitis, Angular stomatitis

o Heart failure (can occur with severe anaemia)

o Neuropsychiatric = Irritability, Dementia, Depression

o Neurological = Subacute combined degeneration of the spinal cord, Peripheral neuropathy

77
Q

What are the appropriate investigations for B12 deficiency?

A

o FBC and blood film = Hypersegmented neutrophils, Oval macrocytes, Circulating megaloblasts

o Pernicious Anaemia Tests = Anti-intrinsic factor antibodies, Anti-parietal cell antibodies, Schilling test

- Serum B12 is not very accurate or reliable

78
Q

Define von Willebrand disease.

A

Bleeding disorder which may present with mucocutaneous bleeding (mouth, epistaxis, menorrhagia), increased bleeding after trauma and easy bruising.

o Type 1 = the von Willebrand factor works well but there isn’t enough of it

o Type 2 = normal levels of von Willebrand factor but it is abnormal and doesn’t function correctly

o Type 3 = no von Willebrand factor

79
Q

What are the presenting signs and symptoms of von Willebrand disease?

A

o Easy bruising

o Epistaxis - hard to stop

o Prolonged bleeding from gums after dental procedures

o Heavy or prolonged menstrual bleeding

o Blood in stools

o Blood in urine

o Heavy bleeding from a cut or other accident

80
Q

What are the appropriate investigations for von Willebrand disease?

A

o Bleeding time = High

o APTT = High

o Factor VIII = High

o vWF = Low in type 1 and 3 but normal in 2

o Ristocetin cofactor = reduced platelet aggregation by vWF in the presence of ristocetin

Y3 Content (16 decks)

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