Haemotology Flashcards
What is haematopoesis?
Commitment and differentiation process of a stem cell to the different types of cells in blood
Where does haematopoesis occur?
**Adults: **
Mainly in bone marrow: pelvis, vertebrae,sternum (known as medullary haematopoesis).
Can occur in liver, thymus and spleen (known as extra medullary haematopoesis)
Where does haematopoesis occur as a foetus
Liver and Spleen
Describe haematopoesis throughout life
Role of erythrocyte?
Transport Oxygen around body
What is erythropoesis
Production of red blood cells
Red blood cell removal occurs in
Spleen
Liver
Bone Marrow
What factor/hormone affects erythropoesis
HYPOXIA: Decrease in oxygen
Stimulates kidneys to produce erythropoetin
What occurs once reticulocyte enter circulation
Red Blood Cell Removal
Red Blood Cell Production
Composition of blood
Where do platelets come from?
Role of platelets?
Help form clots together with clotting factors
What are leukocytes subdivided into
Granulocytes:White blood cells containing pathogen combating granules
Agranulocytes: White blood cells that dont contain pathogen combating granules
What are the 3 main granulocytes
What do agranulocytes divide into?
What is anaemia?
Low haematocrit.
Level <120 g/L in females and <140 g/L in males
RBC importance
Carry O2 and CO2 as well as maintaining blood pH
Where do erythrocytes originate from
Myeloid progenitor cells
Hormones involved in myeloid progenitor -> reticulocyte
Erythropoetin
Thyroid Hormone
Androgens
How do you identify anaemia
Take a full blood count and look at the mean corpuscular volume (average size of persons red blood cell)
Classifications of anaemia
Microcytic anaemia (<80fl)
Normocytic (80-100fl)
Macrocytic (>100fl)
Causes of microcytic anaemia (<80fl)
Iron deficiency
Chronic Inflammatory Disease
Thalassaemia
Investigations carried out for microcytic anaemia
Iron studies
+/- Mentzer Index
Investigations for normocytic anaemia
Reticulocyte Count
Investigations for macrocytic anaemia
Causes of anaemia
- Decreased production of erythropoesis
- Blood Loss
- Increased destruction
Reasons for a decreased production of erythropoesis
Reasons for increased production leading to anaemia
Disseminated Intravascular Coagulation
Thrombotic Thrombocytopenic Purpura
Hemolytic uremic syndrome
What does a red blood cell release when they get destroyed?
Lactate Dehydrogenase
Haemoglobin:
-Globin
-Unconjugated bilirubin
-iron
Blood Test in haemolytic anaemia
Clinical Presentation with someone having anaemia
Types of microcytic anaemia
Fe deficiency
Alpha & Beta Thalassemia
Sideroblastic
What is iron deficiency anaemia
Anaemia due to a decrease in iron
Iron deficiency symptoms?
Anaemia
Fatigue
Headache
Palpitations
Pallor
Nausea
Iron Deficiency
Pica (Pica is the abnormal craving or appetite for non-food substances, such as dirt, ice, paint, or clay.)
Nail changes (koilonychia-spoon shaped nails)
Hair Loss
Glossitis and Angular stomatitis
Restless Leg Syndrome
Patients with iron deficiency anemia are often asymptomatic and have limited findings on examination.
Remember Elder patient presenting with iron deficiency must be investigated for colon cancer malignancy even in the absence of Foecal blood
Risk Factors or Fe2+ anaemia
Decrease in the iron intake or impaired Absorption
Vegan diet
Low socioeconomic status
Gastrectomy
Coeliac Disease
Increase in iron loss
Menorrhagia
Hookworm
NSAID use
Gastrointestinal Bleeding
Increase in iron demand
Pregnancy
Infancy
Side note Our body needs iron 1mg/day. Pregnant women need 5-6mg/day
Differential diagnosis for Fe2+ anaemia
Anaemia
Vitamin B12 deficiency
Folate deficiency
Thalessemia - also hypochromic and microcytic
Anaemia of chronic disease
Sideroblastic
Iron Disorder
Atransferrinaemia
Lead toxicity
Investigations for Fe2+ anaemia
The lower the haemoglobin the more likely there is to be serious underlying pathology and the more urgent is the need for investigation. Patients without a clear physiological explanation for iron deficiency (especially men and postmenopausal women) should be evaluated by gastroscopy/colonoscopy to exclude a source of gastrointestinal bleeding, particularly a malignant lesion.
Full blood count
Haemoglobin/Haematocrit: decreased
Mean cell volume (MCV): decreased
Red cell distribution of width: increased because as iron decreases cells become smaller, increasing distribution
Think In anaemia of chronic disease, the RDW decreases the red blood cells of similar size.
Peripheral blood smear: microcytic, hypochromic red blood cells
Iron studies
Serum iron: decreased
Total iron-binding capacity: increased
Transferrin Saturation: decreased (transferrin is being overproduced to compensate for low iron)
Serum Ferritin: reduced. Ferritin reflects iron stores and is the most accurate test to diagnose iron deficiency anaemia.
Endoscopy: check for peptic ulcer disease, coeliac disease, and other gastrointestinal bleeding conditions
Colonoscopy
Coeliac disease screening at any age?
Remember, IDA may be effectively diagnosed by full blood examination and serum ferritin level in most cases. Serum iron levels should not be used to diagnose iron deficiency.
Side note A complete blood count can help determine the mean corpuscular volume or red blood cell size. Although iron deficiency is the most common cause of microcytic anaemia, up to 40 per cent of patients with iron deficiency anaemia will have normocytic erythrocytes.
Diagnosis for Fe2+ anaemia
Diagnosis of iron deficiency anaemia requires laboratory-confirmed evidence of anaemia and evidence of low iron stores. Anaemia is defined as a haemoglobin level two standard deviations below normal for age and sex.
Think: Iron deficiency anaemia and thalassaemia trait are the commonest causes of microcytic anaemia, but they may coexist. Serum ferritin and haemoglobin A2 quantitation are the two most important investigations to distinguish between iron deficiency anaemia and thalassaemia trait
Causes of Fe2+ anameia
Once iron deficiency anaemia is identified, the goal is to determine the underlying aetiology.
Decreased iron intake
Poverty
Starving
Patient not taking oral iron therapy
Patient taking an iron supplement or multivitamin tablet with insufficient iron content
Inadequate diet or impaired absorption
Concomitant consumption of inhibitors of iron absorption (eg, tea, calcium, antacids, tetracycline, within 2 hours of iron ingestion)
Coexisting inflammation with functional iron deficiency
Intestinal mucosal disorders (eg, coeliac disease, inflammatory bowel disease)
Impaired gastric acid secretion (including use of proton pump inhibitors)
Gastric/intestinal bypass procedures
Helicobacter pylori colonisation
Controlled-release iron formulations may contribute (ie, potential for limited iron absorption in some patients
Increased iron loss
Occult, undiagnosed or recurrent gastrointestinal blood loss (eg, peptic ulcer, malignancy, angiodysplasia, small bowel lesion, parasites)
Other source of recurrent blood loss (eg, menorrhagia due to uterine pathology or an inherited bleeding disorder such as von Willebrand disorder)
Multiple sources of recurrent blood loss (eg, hereditary haemorrhagic telangiectasia)
Ongoing urinary iron losses (eg, significant valve haemolysis)
Renal failure responding to erythropoietin-stimulating agents
Increased iron requirements
Coexisting condition interfering with bone marrow response
Superimposed infection, inflammation, malignancy or renal failure
Concomitant B12 or folate deficiency
Coexisting primary bone marrow disease or suppression
Unknown cause (congenital iron deficiency)
Patients with an underlying condition that causes iron deficiency anemia should be treated or referred to a subspecialist (e.g., gynecologist, gastroenterologist) for definitive treatment.
Remember Gastrointestinal, Genitourinary sources of bleeding should always be excluded
Pathophysiology of Fe2+ anaemia
- Iron is required to form the haem moiety in haemoglobin, myoglobin, and haem enzymes, also known as cytochromes.
- Iron can also be stored in the form of ferritin
- Iron Deficiency can be a result of:
Decreased iron intake because of inadequate diet or impaired absorption
Increased iron loss
Increased iron requirements
Depletion of Iron stores - Anaemia then results in decreased oxygen-carrying capacity and the resultant symptoms of fatigue, low energy level, and dyspnoea on exertion.
Treatment and management for Fe2+ anaemia
Oral iron replacement OR
Parenteral iron replacement
Blood transfusion - serious cases with low haemoglobin
Ascorbic acid (helps in the absorption of iron)
Improve diet
Remember: Oral iron therapy, in appropriate doses and for a sufficient duration, is an effective first-line strategy for most patients.
Complications for Fe2+ anaemia
Diastolic heart failure
Impaired muscular performance
Cognitive impairment
Developmental delays
What do we need iron for?
Iron reacts with protoporphyrin (pigment in RBC) converts it to haem. Haem is essential for haemoglobin. Therefore less iron-less haem-less haemoglobin
What happens if there is less haemoglobin in the blood due to iron. Related condition
Iron deficiency (condition)
It takes up most volume in blood and therefore becomes Microcytic- decrease in MCV less than 80fl.
Iron-deficiency Anaemia and Children (Risk Factors)
Low birth weight
History of prematurity
Exposure to lead
Exclusive breastfeeding beyond four months of life
Weaning to whole milk and complementary foods without iron-fortified foods.
Although iron deficiency anemia is associated with cognitive delays in children, it is unclear if iron supplementation improves cognitive outcomes.
Syptoms Iron deficiency Anaemia and Children
Early symptoms: poor attention span, irritability
Later symptoms & signs: cognitive deficits, lethargy, pallor, poor growth, weakness, listlessness, dyspnoea/ tachypnoea, conjunctival pallor, tachycardia pica, poor feeding, cardiomegaly & signs of cardiac failure
What is thalassemia?
Genetic condition
Two types (alpha and beta)
Missing a globin chain:
alpha: 1aplha + 2beta
beta: 2alpha + 1beta
Where is thalassemia more common in?
Mediterranean ancestry
Thalassemia-microcytic or macrocytic?
microcytic
Treatment of thalassemia
Bone stem cell transplant
Iron
Transfusion
What is alpha thalassemia?
Autosomal recessive
Deletion of alpha globin genes on chromosme 16
No. of defective thalassemia
- Defective alpha gene: Silent carrier
- Defective alpha gene: Alpha thalassemia Minor = mild symptoms
- Defective alpha genes: Haemoglobin H (HbH) disease (excess Beta chains). Enlargens liver, spleen and bone containing bone marrow
- Alpha genes deleted: Hb Bart’s Hydrops foetal
Initial symptoms of alpha thalassemia
Diagnosis of alpha thalassemia
+Haemoglobin electrophoresis
Confirmed by: genetic testing
Treatment for alpha thalassemia
What is beta thalassemia
Autosomal recessive
Mutation in Beta globin gene on chromsome 11. This results in a reduced or absent Beta globin chain synthesis
3 types of beta thalassemia
Symtoms of beta thalassemia
Diagnosis of beta thalassemia
Confirmed : Haemoglobin electrophoresis. Low HbA, High HbF, HbA2
Treatment for beta thalassemia
What is sideroblastic anaemia
type of blood disorder where there’s a buildup of iron in the RBC’s in the body causing them to be immature and dysfunctional
Causes of sideroblastic anaemia
Congenital abnormality
Acquired cause:
-Vitamin B6 deficiency
-Excessive alcohol use
-Lead poisoning
=Decrease in functional haem -> damage to other organs -> anaemia and fatigue
Diagnosis of sideroblastic anaemia
Treatment for sideroblastic anaemia
Removal of Toxins
Pyridoxine, thiamine & folic acid
Macrocytic anaemia
Normocytic (MCV 80-95)
Haemolytic – Sickle cell, Hereditary spherocytosis, G6PDH deficiency, Malaria, Autoimmune Haemolytic
Non-Haemolytic – CKD, Aplastic
What is haemolytic anaemia
Anaemia due to premature destruction of red blood cells
Haemolysis cn occur either
Intravascularly: haemolysis occuring within vasculature
Extravascularly: haemolysis occuring outside vasculature, typically in organs such as spleen or liver
What does haemolysis stimulate the production of
Erythropoietin
What is the reticuloendothelial system
Clearence of old/damaged RBC
Classic laboratory result findings in Haemolytic anaemia
What causes intravascular haemolysis (COMMA)
1.Mechanical Valve (sheer stress) -> haemolysis
2.Microangiopathic haemolysis
3.Cold autoimmune haemolytic anaemia
4.Osmotic lysis following infusion of hypotonic solution
5.Acute transfusion reactions
What causes extravascular haemolysis
Further subdivided into extracorpuscular and intracorpuscular
What is sickle cell anaemia
Sickle cell anaemia is an autosomal recessive disorder causing production of abnormal ß-globin chains. A single amino acid is substituted in the ß-globin chain (Glu to Val at position 6). This results in the production of HbS (haemoglobin Sickle) rather than HbA. The common variants of sickle cell disease are:
Sickle cell anaemia (SS disease) is the most common
Sickle cell trait - causes no disability and protects from malaria except in hypoxia.
Sickle ß Thalassemia (HbS/ßthal)
Sickle haemoglobin C disease (HbSC)
What causes sickle cell anaemia
A missense mutation in the Beta Globin chain
When in sickle cell anaemia does haemoglobin have its sickle shape?
When its not bound to oxygen
What can sickle cell anaemia lead to?
Splenic infarction (<2yo)
Increase risk of infection
Failure to thrive
Chronic renal failure
Gallstone
Iron overload
Lung damage - Hypoxia → fibrosis → pulmonary hypertension
Aplastic crisis - Paravirus B19 infection causing drop haemotocrit
Remember Paravirus B19 infection causing drop haemotocrit in sickle cell and thalassaemia. Treatment is immunoglobulins
Treatment of sickle cell anaemia
Sickle cell anaemia can mean that your immune to what?
Malaria
Diagnosis of sickle cell anaemia
Sickle cell disease can be diagnosed in newborns, as well as older persons, by hemoglobin electrophoresis, isoelectric focusing, high-performance liquid chromatography or DNA analysis
FBC
Blood smear - sickle cells and target cells
Remember Sickle cell trait have normal blood smear, sickle cell anaemia does not!
Side note Target cells are found in Thalassaemia too.
Sickle solubility test
The parents of the affected child with sickle cell aneamia will show features of sickle cell trait.
Sickle solubility test is where a mixture of Hb S in a reducing solution such as sodium dithionite gives a turbid appearance because of precipitation of Hb S, whereas normal Hb gives a clear solution.
Differential diagnosis of sickle cell anaemia
Autoimmune haemolysis
Hereditary spherocytosis
G6PD deficiency
Signs and symptoms of sickle cell anameia
Overview Newborns are usually asymptomatic because babies still have fetal haemoglobin
Vaso-occlusive crisis
Dactylitis (children)
Mesenteric Ischaemia
CNS infarction - seziures, stroke, cognitive defects
Avascular necrosis (neck of femur)
Leg ulcers
Priapism
Fever - infection
Acute chest syndrome
a new infiltrate on chest x-ray
associated with one or more NEW symptoms:
fever, cough, sputum production, dyspnea, or hypoxia.
Acute splenic sequestration
Splenomegaly
Hepatomegaly
Aplastic crisis - due to parovirus infection, with a sudden reduction in bone marrow production
Remember children typically present with acute dactylitis. Males can present with priapism
Pathophysiology of sickle cell anaemia
Substituting one amino acid in the haemoglobin molecule results in sickle haemoglobin. Amino acid changed from Glu to Val. As a result, RBCs sickle in low oxygen states, causing occlusion of blood vessels, increased viscosity, and inflammation.
The average life span of these sickle RBCs is 20 days (120days is normal)
What is hereditary spherocytosis
Genetic
Mutation (ankyrin and spectrin) results in a spherical haemoglobin-loses its biconcave shape. Not good at delivering oxygen effectively as it gets stuck
Risk Factors of hereditary spherocytosis
Family History of anaemia of haemolysis
Northern European
Hereditary spherocytosis symptoms
Splenomegaly
Haemolysis
How to detect hereditary spherocytosis?
Lab: Coombs test
Clinically: Anaemia, jaundice, gall stones, splenomegaly
Treatment for hereditary spherocytosis
There is no cure for HS, but it can be treated. The severity of your symptoms will determine which course of treatment you receive. Options include:
Surgery: In moderate or severe diseases, removing the spleen can prevent common complications that result from hereditary spherocytosis. Your red blood cells will still have their spherical shape but live longer. Removing the spleen can also prevent gallstones.
Not everyone with this condition needs to have their spleen removed. Some mild cases can be treated without surgery. Your doctor might think less invasive measures are better suited for you. For example, surgery is not recommended for children younger than 5 years.
Vitamins: Folic acid, a B vitamin, is usually recommended for everyone with HS. It helps you make new red blood cells. A daily dose of oral folic acid is the main treatment option for young children and people with mild cases of HS.
Transfusion: You may need red blood cell transfusions for severe anaemia.
Light therapy: The doctor might use light therapy, also called phototherapy, for severe infant jaundice.
Vaccination: Getting routine and recommended vaccinations are also important to prevent infectious complications. Infections can trigger the destruction of red blood cells in people with HS.
What is G6PD deficiency
What triggers G6PD Deficiency
Infections
Food
Medications e.g Sulfa-drugs & antimarials
Symptoms of G6PD deficiency
Jaundice
Dark Urine
Back Pain
Anaemia
Typical Findings with someone having G6PD Deficiency
Blood Smear:
Heinz Bodies
Bite Cells
Diagnosis of G6PD Deficiency
Confirmed with Enzyme Assay
Treatment of G6PD Deficiency
Avoid Oxidant Factors
Transfusion (if haemolysis is SEVERE)
What is autoimmune haemolytic anaemia
A condition where the immune system makes antibodies against specific antigens on RBC.
Types of autoimmune haemolytic anaemia
Pathway by which RBC are destroyed
Aetiologies of Autoimmune haemolytic anaemia
Symptoms of autoimmune haemolytic anaemia
Diagnos of haemolytic autoimmune anaemia
Treatment for Autoimmune haemolytic anaemia
Warm: corticosteroids
Cold: Plasmapheresis
Aetiologies of Autoimmune haemolytic anaemia
Diagnos of haemolytic autoimmune anaemia
What is aplastic anaemia, what does it cause?
Form of pancytopenia resulting form the autoimmune destruction of haematopoirtic stem cells
Causes of Aplastic anaemia
Medications
Viruses
Toxins
Genetic Disorders
Treatment for aplastic anaemia
Stem cell transplant
Immunosuppressive therapy
Signs and symptoms of aplastic anaemia
Anaemia
Thrombocytopenia
Neutropoenia
Deficient thrombocytes, leukocytes
Diagnosis of Aplastic anaemia
Diagnosis: Bone marrow biopsy.
What is chronic kidney disease?
Impaired renal function > 3 months based on abnormal structure or function, or GFR <60 for > 3 months with evidence of kidney dysfunction
Signs and symptoms for CKD
Patients with CKD are often asymptomatic until the advanced stages.
Fatigue (Anaemia)
Breathlessness (fluid overload/acidosis)
Pruritis (itching)
Restless legs
Bone pain
Leg swelling
Severe Chronic Kidney Disease (GFR <20mL/min)
Pericarditis
Serositis
Encephalopathy
Gastrointestinal bleeding
Uraemic neuropathy
Examination
Pallor
Lemon tinge skin (Uremia)
Scratch marks from pruritis
Pericardial rub (Uraemic complication)
Pleural effusions
Palpable kidneys (Polycystic Kidney Disease or hydronephrosis)
Peripheral Oedema
Signs of end stage kidney disease
Risk Factors for CKD
Remember Proteinuria, which is a clinical marker for CKD, is also indicative of an increased risk of cardiovascular disease
Causes of chronic kidney disease
Diabetic Nephropathy
Overview Type II diabetes Mellitus is the leading cause of Chronic Kidney Disease. It is classified as a secondary nephrotic syndrome. 20% of people with Type II diabetes will develop end stage kidney disease. Everyone with Diabetes should be screened yearly for microalbuminuria.
Clinical features - Nephrotic Syndrome with signs and symptoms of diabetes (hyperglycemia)
Pathological features Diabetic kidney disease is defined by characteristic structural and functional changes. The predominant structural changes include
Mesengial expansion
Glomerular basement membrane thickening
Glomerular sclerosis
Staging of CKD
The majority of patients with CKD stages 1–3 do not progress to kidney failure. The risk of death from CV disease is far higher than the risk of progression. Mild to moderate CKD is usually managed in general practice or by other physicians caring for the patient. Referral to nephrologist should be considered if:
Proteinuria with haematuria
Stage 4-5 CKD
Suspected rare cause of CKD
Poorly controlled BP
Rapidly falling eGFR
Remember Normal GFR is >90mL/min/1.73m² (130L/day)
Think Low eGFR and raised urine albumin are markers for death, CVD, End-Stage Kidney disease, Acute Kidney Injury
Complications of Chronic Kidney Disease
Hyperkalaemia
Sodium and volume overload
Metabolic acidosis
Hyperphosphataemia
Hypocalcaemia
Anaemia
Hyperkalaemia on ECG is characterised by Peak T wave and later widened QRS complex
Hypocalcaemia on ECG is charactersied by QT complex prolongation primarily by prolonging the ST segment. No change is T wave
Diagnosis of chronic kidney disease
Determining Renal Function
GFR - creatinine clearance and plasma creatinine/urea level
Tubular function - glucosuria, EUC, CMP, plasma albumin
Urine analysis
CT scan - for renal artery stenosis or Urinary tract obstruction
Determine renal structure
Ultrasound - small kidneys suggest chronic disease
CT scan
Cystoscopy
Assess effects of Chronic Kidney Disease on body
FBC
Serum ferritin and iron
CMP
LFT
parathyroid hormone level
Nerve conduction studies
Arterial Doppler studies
Treatment for Chronic Kidney Disease
General and limited progression/complication of CKD
Exclude Acute Kidney injury
Education
Stop Smoking
Weight reduction
Encourage exercise
Avoid alcohol
Vaccination
Fluid intake and diet
Fluid and salt restriction are often important to prevent volume overload.
A low-protein diet has been shown to slow the progression of renal failure in patients with CKD
Phosphate restriction
Potassium restriction
Cardiovascular risk reduction
Hypertension - ACE inhibitors or ARBs
Hypercholesterolaemia - Statins
Aspirin prophylaxis if not contraindicated
Think CKD with hyperkalaemia be careful with using ACE inhibitors or K+ sparing diuretics.
Symptomatic treatment (usually associated with uraemia)
Anorexia
Taste disturbance
Dyspepsia
Constipation
Dyspnoea
Dry skin and pruritus
Anxiety and Depression
Confusion
Restless legs
Treat complications
Anaemia
Erythopoesis stimulating agents
Oral/intravenous iron
Acidosis
Phosphate/calcium/bones
Hyperphosphataemia - Dietary restriction, phosphate binders (aluminium hydroxide)
Vitamin D
Hypocalcaemia - calcimimetics
Secondart/Tertiary hyperparathyroidism - Parathyroidectomy
Preparation for renal replacement therapy
Consider when to start dialysis
Consider suitability for transplant
Dialysis
Peritoneal dialysis
Haemodialysis
Indications for Dialysis (AEIOU)
Acidosis
Electrolytes - refractory hyperkalaemia
Ingestions/intoxication - Barbiturates, lithium, alcohol, salicylates, theophyline
Overload - Pulmonary oedema
Uraemia Complications - pericarditis, refractory pulmonary oedema and encephalopathy
Macrocytic (MCV 95 <) anaemia
Megaloblastic – B12 deficiency, Folate deficiency
Non-megaloblastic – Hypothyroidism, Alcohol excess, Liver disease
What is Vitamin B12 deficiency
Vitamin B12 (cobalamin) deficiency is a common cause of megaloblastic anaemia, a variety of neuropsychiatric symptoms, and elevated serum homocysteine levels, especially in older persons. The recognition and treatment of vitamin B12 deficiency is critical since it is a reversible cause of bone marrow failure and demyelinating nervous system disease
Physiology of Vitamin B12 digestion and Abosorption
Vitamin B12 is found in meat, fish, and dairy products. NOT in plants. The liver can store Vitamin B12 and stores are sufficient for up to 5 years. The daily requirement of vitamin B12 is about 2.4 μg.
Side note Vitamin B12 is found almost exclusively in animal-based foods and is therefore a nutrient of potential concern for those following a vegetarian or vegan diet. Vegans, and anyone who significantly limits intake of animal-based foods, require vitamin B12-fortified foods or supplements.
Remember Vitamin B12 (cobalamin) is a water-soluble vitamin that is crucial to normal neurologic function, red blood cell production, and DNA synthesis.
Risk Factors and Aetiology of Vitamin B12 deficiency
Risk Factors and Aetiology
Decreased ileal absorption
Crohn’s disease
Ileal resection
Tapeworm infestation
Decreased intrinsic factor
Atrophic gastritis
Pernicious anaemia
Postgastrectomy syndrome
Genetic
Transcobalamin II deficiency
Inadequate intake
Alcohol abuse
Older persons
Vegetarians
Alcohol abuse
Prolonged medication use
Metformin
Proton pump inhibitors
Histamine h2 blockers
Signs and symptoms of B12 defiencey
Clinical manifestations of megaloblastic anemia include pallor, tachycardia, weakness, fatigue, and palpitations. The specific mechanism by which vitamin B12deficiency affects the neurologic system is unknown
Remember There are extensive hepatic stores of vitamin B12. There may be a five- to 10-year delay between the onset of deficiency and the appearance of clinical symptoms
Fatigue
Short of breath
Headache
Pallor, hyperpigmentation
Muscle Weakness
Dizziness and Confusion
Paraesthesia (numbness)
Ataxia (loss of normal control of body movements)
Atropic Glosstis (smooth erythematous surface of tongue)
Remember Peripheral neuropathy is the most common symptom of vitamin B12 deficiency. Folate deficiency alone typically has no neurological symptoms.
Aetiology of Vitamin B12 anaemia
Pernicious anaemia (autoimmune-mediated chronic atrophic gastritis) - a most common cause of severe vitamin b12 deficiency
Postsurgical malabsorption
Dietary deficiencies
Vitamin B12malabsorption from food
DIFFERENTIAL DIAGNOSIS OF MACROCYTIC ANAEMIA (MACROCYTOSIS)
Diagnosis of Vitamin B12 deficiency
Treatment of B12 deficiency
High-dose oral Vitamin B12 supplements
Parenteral cyanocobalamin or hydroxocobalamin
Multivitamins - for vegans
Complication of Vitamin B12 deficiency
Neurolgical deficits
Haemotological deficits
Gastric cancer (pernicious anaemia)
What is pernicious anaemia
Pernicious Anaemia is a condition where there is lack of intrisinc factor, a glycoprotein responsible for the absorption of Vitamin B12. Vitamin B12 (Cobalamin) is an essential vitamin responsible for many physiological process in our body. Vitamin B12 deficiency causes megaloblastic anaemia and maybe accompanied by neurological abnormalities.
Clinical presentation of pernciious anaemia
Differential diagnosis for pernicious anaemia
Investigations for perniious anaemia
Aetiology of pernicos anaemia
Pathophysiology of pernciocus anaemia
Treatment for perncious anameia
Complications for perncious anameia
Infertility
Gastric Polyps
Gastric Cancer and Gastric Carcinoid Tumour
Neurological deficits
What is folate deficiency
Decrease in Folate :
Impairs cell division
Increase homocysteine
Signs and symptoms of Folate (Vitamin B9) Deficiency
Diagnosis of Folate deficiency
Treatment of Folate deficiency
What is hypothyroidism
Lack of thyroid hormones
Causes of hypothyroidism
Primary Hypothyroidism: Clinical state resulting from underproduction of T4 and T3. Low free T4 with an elevated TSH is diagnostic of primary hypothyroidism. Autoimmune thyroiditis (Hashimoto’s disease) is the most common cause of primary hypothyroidism.
Secondary (Central) Hypothyroidism: The result of anterior pituitary or hypothalamic dysfunction.
Symtoms of hypothyroidism
Diagnosis of hypothyroidism
Treatment for hypothyroidism
What is leukaemia
Clonal proliferation of hematopoietic stem cells in the bone marrow
What is acute leukaemia?
Clonal proliferation of hematopoietic stem cells in the bone marrow that develops rapidly requires immediate treatment and often presents with symptoms. In acute leukaemia, the cells in the bone marrow are immature (blasts).
What is chronic leukaemia
clonal proliferation of hematopoietic stem cells in the bone marrow that develops slowly, treatment may be delated and often presents asymptomatically. In chronic leukaemia the cells in the bone marrow are still able to mature.
Classifications of leukaemia
Clinical presentation of leukaemia
SUMMARY OF MAJOR LEUKAEMIA
Investigations for Leukaemia
Bone marrow aspirate
Bone marrow biopsy
Cytogenetic testing
Flow cytometry with immunophenotyping
Molecular testing
Peripheral smear
Treatment for leukaemia
A patient with suspected leukemia should be referred to a hematologist-oncologist to confirm the diagnosis and initiate treatment.
Treatment depends on type of leukaemia
Complications of Leukaemia
Tumour Lysis Syndrome
Disseminated Intravascular Coagulopathy - Widespread activation of coagulation, from release of procoagulants into the circulation with consumption of clotting factors and platelets, with ↑risk of bleeding
Hyperviscosity
Death
What is chronic leukaemia
Lots of partially developed white blood cells in the blood over a long period of time
What is the most common cause of chronic leukaemia
Chromosomal abnormalities
Types of chronic leukaemia
Both cells dont work effectively
CML Cells: Divide too quickly
CLL cells: don’t die as they should
Chronic leukaemia vs Acute leukaemia
Chronic: Cells mature only partially
Acute: Cell don’t mature
What is lymphoma
Lymphoma is malignancy originating the lymph nodes. There are two types:
Hodgkins lymphoma
Non-hodgkins lymphoma
Classic Clinical Presentation of lymphoma
1.Lymphadenopathy
2.Constitutional symptoms
Fever
Night sweats
Weight loss
Differential Diagnosis of Lymphadenopathy
Lymphoma
Leukaemia
Metastasis
Infection
Connective tissue disease - rheumatoid arthritis, SLE
Infiltration - sarcoidosis
Drugs - phenytoin
Hodgkins vs Non Hodgkins
What is Hodgkins Lymphoma
So, Hodgkin lymphoma is a tumor derived from lymphocytes - specifically B-cells which mainly reside in lymph nodes.
classifications for Hodgkin Lymphoma
**Classical HL – (90-95% of cases). **The tumour cells in this group are derived from germinal centre B cells, but typically fail to express many of the genes and gene products that define normal germinal centre B cells. Classical HL is further divided into the following subtypes:
Nodular sclerosis classical HL (NSHL) - (most common)
Mixed cellularity classical HL (MCHL)
Lymphocyte-rich classical HL (LRHL)
Lymphocyte-depleted classical HL (LDHL)
**Nodular lymphocyte predominant HL – The tumour cells in this subtype retain the immunophenotypic features of germinal centre B cells.
Risk Factors for Hodgkin lymphoma
History of EBV infection
Family history
Young adults from higher socio-economic status
Immunosuppression
Autoimmune disorders
Signs and symptoms of Hodgkin Lymphoma
Differential diagnosis of Hodgkin lymphoma
Investigations of Hodgkin lymphoma
Pathology of Hodgkin Lymphoma
Pathophysiology for Hodgkin Lymphoma
Treatment for Hodgkin Lymphoma
Complication and prognosis ofHodgkin lymphoma
What is Non-Hodgkin Lymphoma
“Non-Hodgkin” refers to the absence of a key cell that’s seen in Hodgkin lymphoma, the Reed-Sternberg cell.
Non-Hodgkin lymphoma is a tumor derived from lymphocytes - specifically B-cells and T-cells, which mainly live in the lymph nodes and move through the blood and lymphatic system.
Classifications of non-Hodgkin Lymphoma?
Diffuse large B-cell lymphoma (DLBCL)
Follicular lymphoma (FL)
The rest have 1% or lower incidence
Signs and symptoms of non-Hodgkin Lymphoma
Night sweats
Weight loss
Fatigue
Fever
Lympadenopathy
Splenomegaly
Shortness of breath
Cough
Anaemia
Differential diagnosis non-Hodgkin Lymphoma?
Risk Factors of Non-Hodgkin Lymphoma
Investigations and diagnosis for Non-Hodgkin Lymphoma
Pathophysiology of Non-Hodgkins lymphomas
Treatment and management of Non-Hodgkins lymphoma
Complication and Prognosis of Non-Hodgkin lymphoma
Hodgkin’s vs. Non-Hodgkin’s
What is multiple myeloma
Malignant disease of plasma cells in the bone marrow
Who does multiple myeloma usually affect?
Older people
Risk Factors for multiple myeloma
No known hereditary/genetic component or definitive environmental risk factor
Clinical Presentations of multiple myeloma
Pmnemonic: CRAB
Calcium Elevated
Renal Disease
Anaemia
Bone Lesions
Pathology of multiple myeloma
Types of multiple myeloma
Smoldering multiple myeloma (SMM): Asymptomatic
Symptomatic multiple myeloma
Non-secretory mutliple myeloma: Less common (3%)
Causes of multiple myeloma
Genetic mutations
t(14,11)
t(14,6)
Risk Factors of multiple myeloma
Alcohol consumption
Obesity
Radiation
Exposure
Family History
Complications of multiple myeloma
- Spinal Cord compression
- Hypercalcaemia
- Symptomatic Hyperviscosity
- Light Chain Nephropathy
Diagnosis of multiple myeloma
Treatment for multiple myeloma
What is polycythaemia
Excessive red blood cells
=Can result in hyperviscous blood which is prone to clotting
Classifications of polycythaemia
Primary : Known as polycythaemia vera
Secondary:
What is primary polycythaemia
Mutations in bone marrow haematopoietic stem cells cause the excessive production of RBC
90% due to mutation in JAK2 (tyrosine kinase involved in erythropoietin receptor signalling). This means that epo which is usually produced by the kidneys in response to hypoxia is not needed for the proliferation of RBC
What causes secondary polycythaemia
Excessive epo
Appropriate: normal physiological adaptations due to hypoxia like COPD, sleep apnea
Inappropriate: opposite to appropriate e.g Renal cell carcinoma
Signs and symptoms in polycythaemia
Incidental finding in asymptomatic patients
Hyperviscosity: visual changes, muscosal bleeding, headaches
Splenomegaly
Pruritus
Plethora
Erythromelagia
Complications of polycythaemia
- Thrombotic events: DVT
- Myelofibrosis
Investigations for polycythaemia
Initial FBC shows high RBC & haemoglobin
1. Exclude secondary polycythaemia
2. JAK2 mutation
3. Serum EPO
-Primary: EPO Low
-Secondary: EPO High
Management for Polycythaemia
1.Aspirin
2.Venesection
3.Chemotherapy
Too little RBC in blood?
Anaemia <45%
Too much RBC in blood?
Polycythaemia >45%
Too little WBC in blood?
Leukopenia <4,800ul
Too much WBC in blood?
Leucocytosis >11,000 ul
Too little platelets in blood?
Thrombocytopenia <150,000ul
Too much platelets in blood?
Thrombocytosis >450,000 ul
What can cause thrombocytooenia
Diseases that:
Decrease platelet production
Sequestration in spleen
Increase in platelet destruction (non-immune/immune mechanisms)
What can thrombocytopoenia cause
Bleeding from mucocutaneous areas: platelet count <30,000
Disorders like HIT can paradoxically present with thrombotic events
Investigations for thrombocytopoenia
Treatment for thrombocytopoenia
Treating underlying cause:
Transfusing platelets when platelet count <10,000
What is Von Willebrand disease
Quantitative or qualitative deficiency in VWF -> increases risk of bleeding
Is Von Willebrand Disease inherited?
Most cases are inherited
-People can acquire it
Classifications of Von Willebrand Disease
Type I: Moderate symptoms
Type II: Moderate symptoms
Type III: Severe Bleeding
What can cause type I & II Von Willebrand Disease
Heavy Menstrual periods
Mucocutaneous/Nose bleeding
What do patients with Type III Von Willebrand Disease present with
Present with severe bleeding in joints and muscles. Rarely bleeding in the gut
Diagnosis of Von Willebrand Disease
Serum tests:
-VWF antigen
-Ristocetin: Test activity
Treatment for Von Willebrand disease
What is haemophilia
Bleeding disorder caused by an impaired coagulation cascade
X-Linked recessive
What causes haemophilia A
Mutations in genes for factor VIII
What causes haemophilia B
Mutations in genes for factor IX
Treatment for Haemophilia
Supplementing missing factor
Acquired cause of haemophilia
Liver Failure
Vitamin K deficiency
Autoimmunity against a clotting factor
Disseminated intravascular coagulation: consumes clotting factors
Signs and symptoms of haemophilia
Symptoms depend on degree of mutation
Major complication of haemophilia
Bleeding in the brain:
-> Stroke
-> Increased intracranial pressure
Diagnosis for haemophilia
Diagnosis for haemophilia
What is disseminated Intravascular Coagulation
When haemostasis starts to run out of control resulting in widespread clotting leading to organ ischaemia. At the same time it depletes clotting factors and increase bleeding
Common causes of disseminated intravascular coagulation (DIC)
Pathophysiology of DIC
Signs & Symptoms of DIC
Diagnosis for DIC
Differential dioagnosis for DIC
Treatment for DIC
Oxygen
IV fluid
What causes tumour lysis syndrome
Caused when tumour cells release there intra-cellular content into the bloodstream either spontaneously or as a result of treatment.
This leads to an increased:
DNA purine and pyramidine
Hyperkalemia
Hyperphosphataemia
Hypocalcaemia
Lactic Acid
Complication of tumour lysis syndrome
Acute Kidney Injury
Arryhythmia
Tetany Seizures
At risk for developing tumour lysis syndrome
Large Tumour burden
Rapidly dividing cells: acute leukaemia, high grade lymphoma
Chemotherapy
Tumour lysis syndrome can occur…
Spontaneously (Before treatment)
Within weeks after treatment
Management of tumour lysis syndrome
- Identify those at risk and therefore provide:
Prophylaxis
Intravenous hydration
Allopurinol
Rasquricase - Treat tumour lysis syndrome and it’s complications
Dialysis
Diagnosis of tumour lysis syndrome
Cairo and Bishop diagnosis
What is Activated Partial Thromboplastin Clotting Time (APTT)
The aPTT is 1 of several blood coagulation tests. It measures how long it takes your blood to form a clot.
Normally, when 1 of your blood vessels is damaged, proteins in your blood called clotting factors come together in a certain order to form blood clots and quickly stop bleeding. The aPTT test can be used to look at how well those clotting factors are working.
What is a Prothrombin Time Test and INR (PT/INR)
A prothrombin time (PT) test measures how long it takes for a clot to form in a blood sample. An INR (international normalized ratio) is a type of calculation based on PT test results
Diagnosis for Fe2+ anameia
Diagnosis
Diagnosis of iron deficiency anemia requires laboratory-confirmed evidence of anemia, as well as evidence of low iron stores. Anemia is defined as a hemoglobin level two standard deviations below normal for age and sex
Think Iron deficiency anaemia and thalassaemia trait are the commonest causes of microcytic anaemia, but they may coexist. Serum ferritin and haemoglobin A2 quantitation are the two most important investigations to distinguish between iron deficiency anaemia and thalassaemia trait
Differential diagnosis of sickle cell anaemia
Autoimmune haemolysis
Hereditary spherocytosis
G6PD deficiency
What is leukaemia
Clonal proliferation of hematopoietic stem cells in the bone marrow
What is leukaemia
Clonal proliferation of hematopoietic stem cells in the bone marrow
Target cells
‘Tear-drop’ poikilocytes
Spherocytes
Basophilic stippling
Heinz Bodies
‘Pencil’ poikilocytes
Ritcher’s transformation
occurs when leukaemia cells enter the lymph node and change into a high-grade, fast-growing non-Hodgkin’s lymphoma. Patients often become unwell very suddenly.
Ritcher’s transformation is indicated by one of the following symptoms:
lymph node swelling
fever without infection
weight loss
night sweats
nausea
abdominal pain
Chronic lymphocytic leukaemia: complications
Complications
anaemia
hypogammaglobulinaemia leading to recurrent infections
warm autoimmune haemolytic anaemia in 10-15% of patients
transformation to high-grade lymphoma (Richter’s transformation)
A 10-year-old child with a history of neonatal jaundice develops pallor and jaundice after an upper respiratory tract infection associated with erythematous cheeks. Splenomegaly is noted on examination is a stereotypical history of:
Hereditary spherocytosis
Multiple myeloma histological features
monoclonal IgG or IgA paraprotein band, osteolytic lesions, increased infections
A 65-year-old man presents with back pain and lethargy. Bloods show a raised calcium, renal dysfunction and a raised ESR
- multiple myeloma
What supports the diagnosis of multiple myeloma
Bence-Jones protein
A Bence Jones protein is a monoclonal globulin protein or immunoglobulin light chain produced by neoplastic plasma cells. Presence of Bence Jones protein in the urine associated with anaemia and hypercalcemia make multiple myeloma the most likely diagnosis.
what is the pathophysiology that leads to the hypercalcemia
through increased osteoclast activity in response to cytokines released by the myeloma cells
Chronic lymphocytic leukaemia is most associated with
Hypogammaglobulinaemia
Chronic myeloid leukaemia: Presentation
anaemia: lethargy
weight loss and sweating are common
splenomegaly may be marked → abdo discomfort
an increase in granulocytes at different stages of maturation +/- thrombocytosis
decreased leukocyte alkaline phosphatase
may undergo blast transformation (AML in 80%, ALL in 20%)
Chronic myeloid leukaemia: Management
imatinib is now considered first-line treatment
inhibitor of the tyrosine kinase associated with the BCR-ABL defect
very high response rate in chronic phase CML
hydroxyurea
interferon-alpha
allogenic bone marrow transplant
CLL is associated with
warm autoimmune haemolytic anaemia
CML is characterised by
Philadelphia chromosome, where a translocation between chromosome 9 and 22 causes the formation of the BCR-ABL gene.
The most common form of leukaemia in adults is
CLL
ALL CeLLmates have CoMmon AMbitions
Under 5 and over 45 – acute lymphoblastic leukaemia (ALL)
Over 55 – chronic lymphocytic leukaemia (CeLLmates)
Over 65 – chronic myeloid leukaemia (CoMmon)
Over 75 – acute myeloid leukaemia (AMbitions)
Histological Features of Hodgkin lymphoma
secondary cause of polycythaemia
COPD
