Haematology conditions Flashcards
What is aplastic anaemia?
Rare stem cell disorder characterised by diminished haematopoietic precursors in the bone marrow and deficiency of all blood cell elements (Pancytopenia)
Leads to pancytopenia and hypoplastic marrow (Marrow stops making cells)
What causes aplastic anaemia?
Most are AI triggered by drugs, viral infection or irradiation
>40% idiopathic
Acquired (Drugs, chemicals, radiation, viral infection, paroxysmal nocturnal haemoglobinuria)
Inherited (Fanconi’s anaemia, dyskeratosis congenita)
What are the symptoms of aplastic anaemia?
Slow-onset (months) or Rapid-onset (Days)
Anaemia symptoms
Thrombocytopenia (Easy bruising, bleeding gums, epistaxis)
Leukopenia (increased frequency and severity of infections)
What are the signs for aplastic anaemia?
Pallor Petechiae Bruises Multiple infections No Organomegaly
What investigations are done for aplastic anaemia?
FBC (Low Hb, Low platelets, Low WCC, Normal MCV, Low/absent reticulocytes)
Blood film (exclude leukaemia)
Bone marrow trephine biopsy
Fanconi’s anaemia (Check for presence of increased chromosomal breakage in lymphocytes cultures in the presence of DNA cross-linking agents)
What is Haemolytic anaemia?
Premature erythrocyte breakdown caused by shortened erythrocyte life span (<120 days) with anaemia.
Occurs in circulation to damaged RBCs or in the reticuloendothelial system
What causes Haemolytic anaemia?
Hereditary sepherocytosis Hereditary elliptocytes G6PD deficiency Pyruvate kinase deficiency Sickle cell disease Thalassemia AIHA Isoimmune Drugs (Penicillin, Quinine) Trauma (MAHA) Malaria Sepsis Marchiafava-Micheli disease
What are the symptoms of Haemolytic anaemia?
Jaundice Heamaturia Dark Urine Anaemia Can often be asymptomatic Family history Race Recent travel
What are the signs of haemolytic anaemia?
Pallor
Jaundice
Hepatosplenomegaly
Leg ulcers
Which investigations are needed for Haemolytic anaemia??
- FBC (Low Hb, High reticulocytes, High MCV, High unconjugated bilirubin, low haptoglobin)
- U&Es
- Folate
Blood film
[May identify specific abnormal cells pointing to the diagnosis]
Urine (Haemoglobin, Blood, high urobilinogen)
Direct coomb’s test
Osmotic fragility test / spectrin mutation analysis
Ham’s test
Hb electrophoresis or enzyme assays
Bone marrow biopsy (Rare)
Which cells on the blood film points to diagnosis?
Hypochromic microcytic anaemia - thalassemia
Spherocytes - Hereditary spherocytosis or AIHA
Elliptocytes - Hereditary Elliptocytes
Sickle cells - Sickle cell anaemia
Schistocytes - MAHA
Malarial parasites
Heinz bodies (bite cells) - G6PD deficiency
What is Coomb’s test?
A test for AIHA, identifies erythrocytes coated with antibodies
What is Ham’s test?
Lysis or erythrocytes in acidified serum in paroxysmal nocturnal haemoglobinuria
What is Macrocytic anaemia?
Anaemia with Red blood cells that are larger than normal.
Usually results from abnormal haematopoiesis so that red cell precursors continue to synthesise haemoglobin and other cellular proteins but fail to divide normally
What causes macrocytic anaemia?
Oval macrocytes
Pernicious Anaemia
B12 deficiency
Folate deficiency
Drugs (Methotrexate, hydroxyurea, azathiopine, zidovudine)
Non megaloblastic causes (Alcohol excess, Myelodysplasia, multiple myeloma, hypothyroidism, aplastic anaemia, haemolysis, drugs, pregnancy)
What are the symptoms of macrocytic anaemia?
Mild is asymptomatic Shortness of breath Fatigue Palpitations Exacerbation of angina Looking pale Family history of AI disease Previous GI surgery Symptoms of cause (weight loss, diarrhoea)
What are the signs of macrocytic anaemia?
Pallor Tachycardia Breathlessness Pernicious anaemia (mild jaundice, glossitis, angular somatitis, weight loss) For B12 deficiency: - Peripheral neuropathy - Ataxia - Subacute combined degeneration of the spinal cord - Optic atrophy - Dementia - Positive babinski's sign
What are the investigations for macrocytic anaemia?
FBC LFT ESR TFT Serum B12 Red cell folate Anti-parietal cell Blood film Schilling test BM biopsy
What is the management of Pernicious anaemia?
No neurological deficits:
- IM hydroxycobalamin 3x/week for 2 weeks then 1mg/3 months
Neurological deficits:
- 1mg every other day until no further improvement then 1mg/2 months
What is the management of B12/Folate deficiency?
B12: Dietary supplements (PO cyanocobalamin)
Folate: Oral folic acid
If both B12 and folate, need to do B12 first
What are the complications of macrocytic anaemia?
Pernicious anaemia - Gastric cancer, subacute combined degeneration of spinal cord
Folate in pregnancy leads to increased risk of neural tube defects
What is Microcytic anaemia?
Anaemia assocaited with low MCV (<80fl)
What causes microcytic anaemia?
Iron deficiency (Blood loss, reduced absorption, increased demands, reduced intakes)
Anaemia of chronic disease
Sideroblastic anaemia
Thalassemia
What are the symptoms of microcytic anaemia?
Tiredness Lethargy Malaise Dyspnoea Pallor Palpitations Exacerbation of ischaemic conditions Lead poisoning
What are the signs of microcytic anaemia?
Anaemia: - Pallor - Brittle nails and hair - Kolionychia - Glossitis - Angular stomatitis Lead poisoning signs: - Blue gumline - Peripheral nerve lesions - Encephalopathy - Convulsions - Reduced consciousness
What investigations are done for microcytic anaemia?
FBC (Low Hb, MCV; reticulocytes) Iron studies Serum Lead CRP/ESR Blood film Haemoglobin electrophoresis
What is seen on blood film for causes of microcytic anaemia?
IDA - Microcytic - Hypochromic - Anisocytosis - Poikilocytosis Sideroblastic anaemia - Dimorphic blood film - Hypochromic microcytic cells Lead poisoning - Basophilic stippling Sideroblastc anaemia - Ring sideroblasts in bone marrow
Which special investigations are needed for Iron deficiency anaemia if >40 and post-menopausal women or males?
Upper GI endoscopy
Colonoscopy
Urine dip
What is the management for Iron deficiency anaemia?
Oral iron supplements (Ferrous fumarate)
IV iron if oral ineffective
What is the management for sideroblastic anaemia?
Treat cause
Pyroxidine in inherited forms
Blood transfusion and iron chelation
What is the management for lead poisoning?
Remove source
Dimercaprol or D-Penicillinamine
What are the complications of microcytic anaemia?
High-output cardiac failure
complications related to cause
What is normocytic anaemia?
Anaemia with a normal MCV (80-100)
What causes normocytic anaemia?
Acute blood loss (peptic ulcer, oesophageal varices, trauma) Failure of RBC production Heamolysis Uncompensated increase in plasma volume Pooling in the spleen Anaemia of chronic disease
What causes a failure of RBC production?
Bone marrow failure or suppression Bone marrow infiltration Renal failure Vitamin B2/B6 deficiency Hypothyroidism
What are the symptoms of RBC production?
Breathlessness
Fatigue
Conjunctival pallor
What are the signs of RBC production?
Conjunctival pallor
Angular stomatitis
What investigations are done for Normocytic anaemia?
FBC (check Hb and MCV)
Check ferritin for IDA
Check history for haemorrhage
If WCC low or platelets low, suspect marrow failure
What is Polycythaemia?
An increase in haemoglobin concentration above the upper limit of normal for a person’s age and sex
What are the 2 classes of Polycythaemia?
Relative polycythaemia
Absolute polycythaemia
What is the difference between relative polycythaemia and absolute polycythaemia?
Relative polycythaemia = Normal red cell mass but low plasma volume
Absolute polycythaemia = Increased red cell mass
What causes polycythaemia?
Primary - Polycythaemia rubra vera Secondary - Appropriate increase in EPO - Inappropriate increase in EPO - Relative polycythaemia
What causes polycythaemia rubra vera?
- Characterised by clonal proliferation of myeloid cells
- Have varied morphological maturity and haematopoietic efficiency
- Mutations in JAK2 tyrosine kinase are involved
What are the causes of increased EPO?
Appropriate: - Chronic hypoxia Inappropriate: - Renal - Hepatocellular carcinoma - Fibroids - Cerebellar haemangioblastoma - secondary polycythaemia due to EPO abuse
What are the causes of Relative polycythaemia?
- May be acute - dehydration
- Chronic from associated with obesity, hypertension, high alcohol and tobacco intake
- Gaisbock’s syndrome
What are the risk factors for polycythaemia?
Age Hypertension Diabetes Smoking Alcohol COPD Altitude Congenital heart disease Cancer Family history
What are the symptoms of polycythaemia?
Headache Dyspnoea Tinnitus Blurred vision Pruritus after hot bath Burning sensation in fingers and toes (erythromyalgia) Night sweats Thrombosis Pain from peptic ulcer disease Angina Gout Choreiform movements
What are the signs of polycythaemia?
Plethoric complexion (red, ruddy) Scratch marks from itching Conjunctival suffusion (redness of the conjunctiva)
What are the investigations for polycythaemia?
FBC (High Hb, High Hct, Low MCV) Isotope dilution techniques JAK2 mutation EPO Bone marrow trephine and biopsy Secondary: High serum EPO, Exclude lung disease, Check for EPO-secreting tumours
What is sickle cell disease?
Autosomal recessive single gene defect in the beta chain of the haemoglobin, which results in production of sickle cell haemoglobin.
May occur if one HbS obtained from one parent or another bad haemoglobin e.g. Beta thalassaemia inherited from another patient
What causes sickle cell disease?
Sickling with RBCs containing sickle haemoglobin become rigid and distorted into a crescent shape
Valin replaes glutamic acid at 6th AA of beta globin chain
Which factors precipitate sickling?
Infeciton
Hypoxia
Acidosis
Dehydration
What are the risk factors for sickle cell disease?
Genetic
What are the symptoms of sickle cell disease?
Autosplenectomy Abdominal pain due to mesenteric ischaemia Bone pain Avascular necrosis Myalgia and arthralgia Leg ulcers Low flow priapism CNS Retina Painful erection Impotence Breathlessness Cough Pain Fever Symptoms of aplastic anaemia Anaemia and infection
What are the signs of sickle cell disease?
Secondary to vaso-occlusion, ischaemia or infarction
- Bone - joint or muscle tenderness or swelling
- Short digits - infarction in small bones of hands
Retina - cotton wool spots due to retinal ischaemia
Organomegaly (spleen)
Priapism
Lethargy
Pallor
What are the investigations for sickle cell disease?
FBC
U&Es
Blood film (Sickle cells, anisocytosis, hyposplenism (target cells, howell jolly bodies))
Sickle solubility test (Dithionate - increase turbidity)
Hip X-ray (femoral head common site of avascular necrosis)
MRI/CT head (neuro complications)
What are the managements for acute sickle cell disease?
Oxygen IV fluids Strong analgesia Antibiotics Antihistamine Cross match blood Transfusion if Hb/reticulocytes fall
What is the chronic management of sickle cell disease?
Infection prophylaxis (penicillin V, vaccines - Pneumococcus, Haemophilus influenzae B) Folic acid (severe or pregnant) Hydroxyurea/hydroxycarbamide Red cell transfusion Stroke prevention Advice Surgical
What are the complications of sickle cell disease?
Anaemia Opioid dependence Iron overload from chronic transfusion Liver complications and cholelithiasis Avascualr necrosis of hip or shoulder Dactylitis Leg ulcer Cardiovascular malformations Priapism Splenic sequesteration Pulmonary HTN Renal abnormalities Growth and developmental delay Stroke and CNS disease Proliferative retinopathy and retinal haemorrhages Transient red cell aplasia Malaria Learning difficulties
What is Thalassaemia?
A group of genetic disorders characterised by reduced globin chain synthesis. Under or no production of globin chain.
What causes thalassaemia?
Autosomal recessive
Result in imbalance of globin chain production an deposition in erythroblasts and erythrocytes
What are the types of thalassaemia?
Alpha thalassaemia
Beta thalassaemia
What are the risk factors for thalassaemia?
Family history
Mediterranean origin
What are the symptoms of thalassaemia?
Beta: - Severe anaemia - Present 3-6 months Alpha/Beta: - May be asymptomatic - Detected during routine blood tests or due to family history
What are the signs of Thalassaemia?
Beta thallasemia major
- Pallor
- Malaise
- Dyspnoea
- Mild Jaundice
- Extramedullary haematopoiesis (frontal bossing & hepatosplenomaegaly)
- Thalassaemia facies (chipmunk-like cheeks, prominent forehead)
- Hepatosplenomegaly
- Osteopenia
- Patients with Beta-thalassemia intermedia
What are the investigations for thalassaemia?
FBC (Anaemia, microcytic, low MCH) Blood film - Hypochromic microcytic anaemia - Target cells (alpha) - Howell jolly bodies - Nucleated red cells - High reticulocyte count Hb Electrophoresis (Absent or reduced HbA, high HbF) Bone marrow (Hypercellular, erythroid hyperplasia) Genetic testing Skull X-ray
What is antiphospholipid syndrome?
Condition characterised by presence of antiphospholipid antibodies in the plasma, venous and arterial thromboses, recurrent foetal loss and thrombocytopenia
What causes antiphospholipid syndrome?
Occurs as a primary disease but 20-30% associated with SLE
APL directed against plasma proteins bound to anionic phospholipids
APL develop in susceptible individuals
Once APL present, a ‘second-hit’ needed to develop the syndrome
What are the risk factors for antiphospholipid syndrome?
History of SLE AI disorders (thyroid/coeliac/addison's)
What are the symptoms of antiphospholipid syndrome?
Recurrent miscarriages History of arterial thromboses (stroke) History of venous thromboses (DVT, PE) Headaches, Migraines Chorea Epilepsy
What are the signs of antiphospholipid syndrome?
Livedo reicularis
Signs of SLE - malar flush, discoid lesions, photosensitivity
Signs of valvular heart disease
What are the investigations for antiphospholipid syndrome?
FBC (Low platelets)
ESR (normal)
U&Es (APL nephropathy)
Clotting screen (High aPTT)
ALT ELISA (Positive) or lupus anticoagulant assays
Antibodies present (Lupus anticoagulant, anti-cardiolipin, antiphospholipid anti b2-microglobulin)