Paediatric - Haematology Flashcards
WHO defines anaemia as…
- Haemoglobin (Hb) <130g/L in men aged 15 years and older
- Haemoglobin (Hb) <120g/L in non-pregnant women aged 15 years and older
Most common cause of anaemia worldwide?
Iron deficiency
Name 3 causes of iron-deficiency anaemia
Excessive blood loss (menorrhagia/gastric ulceration/angiodysplasia); Diet; Failure of Fe absorption (tetracyclines/antacids/PPIs/Calcium/Coeliac); Excessive requirement for Fe (pregnancy/rapid growth in children)
Name 3 symptoms of iron-deficiency anaemia
Fatigue, SOB on exertion, Palpitations, Headache, Tinnitus, Angina, Taste disturbance, Changes in hair/hair loss
Name 3 signs of iron-deficiency anaemia
Pallor, Koilonychia, Angular cheilitis, Atrophic glossitis,
What 3 investigations confirm Dx of iron-deficiency anaemia?
FBC (hypochromia = low MCH, microcytosis = low MCV); Serum Ferritin (12-15mcg/L confirms Dx); Blood film (anisocytosis + poikilocytosis)
Name 3 possible ways of treating iron-deficiency anaemia
Iron salts, Iron-rich foods (green vegetables, meat, apricots, prunes), Iron tablets (Ferrous sulphate)
Name 3 side-effects of iron supplementation
Constipation, Black stool, Diarrhoea, Heartburn, Nausea, Abdominal/epigastric pain
Where in the body does vitamin B12 absorption take place? (and what protein is required?)
Terminal Ileus and Intrinsic Factor (required for transport across intestinal mucosa)
What type of cell secretes Intrinsic Factor?
gastric mucosal (parietal) cells
Name 3 foods that contain Vitamin B12
meat, fish, dairy products
Name 3 causes of Pernicious Anaemia
Gastric causes (gastrectomy, gastric resection, atrophic gastritis, H. pylori infection or IF deficiency); Intestinal causes (malabsorption, ileal resection, Crohn’s disease); Diet (vegan); Drugs (colchicine, neomycin, metformin, anticonvulsants, long-term PPI use)
Incidence of Pernicious Anaemia in UK population per 100,000 per annum?
1-5/100,000 per annum
What is the most common cause of B12 deficiency and megaloblastic anaemia and what age range does it most commonly occur in?
Pernicious Anaemia and 40-70 years old
Name 3 symptoms of Pernicious Anaemia
fatigue, dyspnoea, faintness, palpitations and headache, neurological Sx (paraesthesia, neuropathy), neuropsychiatric Sx (irritability, depression, psychosis), Subacute combined degeneration of the spinal cord (impairment of pain, temperature and touch sensations)
Name an antibody screening test which could help determine the aetiology of vitamin B12 deficiency
Autoantibody screen, Intrinsic Factor Antibody, Gastric anti-parietal cell antibodies
Name an investigation which helps confirm a diagnosis of pernicious anaemia
Serum B12, FBC (^MCV,↓WCC+platelets), gastroscopy/gastric secretions, bone marrow aspiration, Schilling test
Name one disease associated with pernicious anaemia (ie. patients at higher risk of developing this disease)
Gastric cancer, primary hypothyroidism, thyrotoxicosis, Hashimoto’s thyroiditis, Addison’s disease, type 1 diabetes, hypoparathyroidism, vitiligo
Suggest a treatment for Pernicious Anaemia
Hydroxocobalamin 1mg IM or oral B12
Name one example for each anaemia: a) Microcytic hypo chromic b) normocytic normochromic c) Macrocytic
a) Thalassaemia/iron deficiency b) Haemolytic/marrow infiltration c) Folate deficiency/B12 deficiency (pernicious)
Where in the body is Folate absorbed?
upper third of the small intestine
Why does folate play a part in mental development and what can be caused by lack of folate in pregnancy?
Folate plays an important role in the production of red blood cells and helps your baby’s neural tube develop into their brain and spinal cord (neural tube defect)
Name 3 causes of folate deficiency
Diet (malabsorption/coeliac,malnutrition,alcohol excess); Excessive requirement (pregnancy, malignancy,anaemia, inflammation); Excessive urinary excretion; Antifolate drugs (Trimethoprim,anticonvulsants); Genetic disorders (SLC46A1)
Name a symptom of folate deficiency
Glossitis, Paraesthesia, numbness, visual disturbance, cognitive changes
Name a blood test (other than serum folate) for folate deficiency and the result
FBC (^MCV); Blood film (leukopenia,thrombocytopenia,microcytes with hypersegmented polymorphs);
Suggest a prescription for an otherwise healthy adult with folate deficiency
5mg of folic acid daily
What is Haemolysis?
Premature breakdown of RBCs
What is the normal lifespan of a red blood cell?
120 days
Name a genetic cause of Haemolytic Anaemia
Hb defects - sickle cell/Thalassaemia; red cell defects - spherocytosis, elliptocytosis; enzyme deficiency - glucose-6-phosphate dehydrogenase deficiency / pyruvate kinase deficiency
Name an enzyme defect which causes Haemolytic Anaemia
glucose-6-phosphate dehydrogenase deficiency / pyruvate kinase deficiency
Name an acquired cause of Haemolytic Anaemia
Immune - haemolytic disease of newborn, Autoimmune - SLE/CLL/lymphoma; Drug-related - penicillins/cephalosporins/sulfonamides
Name a non-immune cause of Haemolytic Anaemia
Trauma - cardiac haemolysis; Infection - malaria/sepsis; Hypersplenism; membrane disorders; paroxysmal nocturnal haemoglobinuria; liver disease
Name 2 investigations for Haemolytic Anaemia
FBC (normal platelet count+MCV in most haemolytic anaemias); Coombs’ test; Cold agglutinins; Ultrasound of spleen; CXR/ECG for cardiopulmonary status
Sickle cell anaemia and Thalassaemias both follow what inheritance pattern?
Autosomal recessive
Where is the mutation in a sickle cell haemoglobin?
17th nucleotide of the beta globin gene is changed from thymine to adenine and the amino acid glutamic acid is replaced by valine at position 6 in the beta globin chain
Sickle cell anaemia is most common in which ethnicity?
Sub-saharan African
Name a type of sickle cell crisis
Vaso-occlusive crisis, Aplastic crisis, Sequestration crisis, Hyperhaemolytic crisis,
What is the most common type of sickle cell crisis?
vaso-occlusive crisis (Acute Chest Syndrome + Stroke)
Name 3 investigations for sickle cell anaemia
FBC (Hb=6-8g/dL), blood film, sickle solubility test, haemoglobin electrophoresis
Name 3 complications of sickle cell anaemia
chronic pain, nocturnal enuresis, infection, stroke, priapism, cardiac failure, chronic pulmonary disease, gallstones, eyes (retinopathy), CKD, splenic infarction, leg ulcers, avascular necrosis, chronic organ damage, iron overload, learning difficulties
What is Thalassaemia?
Genetic diseases of unbalanced Hb synthesis, with under-production of one global chain
Name 3 investigations for Beta Thalassaemia
FBC, blood film, Serum iron, HbA2, HbF, Hb electrophoresis
Name 2 treatments for Beta Thalassaemia
Regular blood transfusions, Iron-chelators (prevent iron overload), Ascorbic acid (^excretion of iron), Desferrioxamine, splenectomy, hormonal replacement, Marrow transplant
What are the four types of global chains?
Alpha, Beta, Gamma, Delta
what is the most common manifestation of CMV disease in patients who are HIV-positive?
Retinitis
A 2-year-old boy is presented with multiple petechiae and excessive bruising on his shins. He was previously fit and well apart from a an illness two weeks ago which was diagnosed by the general practitioner as a viral upper respiratory tract infection. He is apyrexial. Investigations including blood smears reveal thrombocytopaenia with all other parameters reported as normal.
Which of the following is the most likely diagnosis?
TTP / CML / Essential Thrombocytopaenia / ITP
ITP is often preceded by a viral illness and the presence of an isolated thrombocytopaenia is typical of ITP. In TTP, schistocytes are often seen on blood smears.
Although essential thrombocythaemia may cause bleeding, the typical patient is an adult above the age of 40.
Name some symptoms of Disseminated intravascular coagulopathy (DIC)
- Bleeding from at least three unrelated sites is typical and likely sites include: Ears, nose and throat. Gastrointestinal tract. Respiratory tract. Site of venepuncture or IV infusion. - Confusion or disorientation. - Fever. - Signs of haemorrhage. - Signs of adult respiratory distress syndrome (ARDS). - Skin may show various signs including: Petechiae. Purpura. Haemorrhagic bullae. Acral cyanosis. Skin necrosis of lower limbs (purpura fulminans). Signs of thrombosis. Localised infarction and gangrene.
How might Sepsis progress into Disseminated intravascular coagulopathy (DIC)
- Coagulation system causes deposition of fibrin throughout the circulation, further compromising organ and tissue perfusion.
- Consumption of platelets and clotting factors, as they are being used up to form the blood clots.
- Leads to Thrombocytopenia, haemorrhages and an inability to form clots and stop bleeding. This is called disseminated intravascular coagulopathy (DIC).
Name some signs of sepsis in children
- Deranged physical observations
- Prolonged capillary refill time (CRT)
- Fever or hypothermia
- Deranged behaviour
- Poor feeding
- Inconsolable or high pitched crying
- High pitched or weak cry
- Reduced consciousness
- Reduced body tone (floppy)
- Skin colour changes (cyanosis, mottled pale or ashen)
What temperature requires all infants under 3 months to be treated urgently for sepsis, until proven otherwise.
38ºC or above
Immediate management of a child with Sepsis
Sepsis is a medical emergency and needs to be managed urgently. Call for senior help early for experienced support.
- Give oxygen if the patient has evidence of shock or oxygen saturations are below 94%
- Obtain IV access (cannulation)
- Blood tests, including a FBC, U&E, CRP, clotting screen (INR), blood gas for lactate and acidosis
- Blood cultures, ideally before giving antibiotics
- Urine dipstick and laboratory testing for culture and sensitivities
- Antibiotics according to local guidelines. They should be given within 1 hour of presentation.
- IV fluids. 20ml/kg IV bolus of normal saline if the lactate is above 2 mmol/L or there is shock. This may be repeated.
Which of the following would you expect to precede Idiopathic thrombocytopenic purpura?
Epileptic fit / Asthma Attack / Glandular Fever / Constipation / Stress
Glandular Fever
Idiopathic thrombocytopenic purpura may be preceded by a self-limiting viral infection
What haem condition is a key differential diagnosis of a non-blanching rash?
ITP
Idiopathic thrombocytopenic purpura usually presents in children of what age?
Under 10 years old
Name the three classic features of ITP
- Bleeding, for example from the gums, epistaxis or menorrhagia
- Bruising
- Petechial or purpuric rash, caused by bleeding under the skin
(Petechiae are pin-prick spots (around 1mm) of bleeding under the skin. Purpura are larger (3 – 10mm) spots of bleeding under the skin. When a large area of blood is collected (more than 10 mm), this is called ecchymoses. These are all non-blanching lesions)
What treatment may be required if a patient with ITP is actively bleeding or severe thrombocytopenia (platelets below 10)?
- Prednisolone
- IV immunoglobulins
- Blood transfusions if required
- Platelet transfusions only work temporarily
What medication should a patient with ITP avoid?
NSAIDs, aspirin and blood thinning medi
What are some physical abnormalities seen in Fanconi Anaemia?
(+ what conditions are these patients susceptible to?)
Physical abnormalities
- Skin may be hyperpigmented with café-au-lait spots.
- Often low birth weight and small for age.
- ace may be triangular in shape.
- Thumbs and radii can show structural abnormalities (usually aplasia or hypoplasia), as can the fingers and toes.
- Microcephaly, microphthalmia and deafness occur.
- Cardiac and renal malformations are encountered.
- Gonads in older patients tend to be atrophic or dysmorphic with a range of associated genitourinary abnormalities, causing reduced fertility.
Consider Fanconi Anaemia in adult patients presenting with:
- Aplastic anaemia.
- Myelodysplastic syndrome.
- AML.
- HNSCC.
- Gynaecological cancers in women less than 50 years of age.
What inheritance pattern does Fanconi Anaemia follow?
Autosomal recessive
What test can be used to check for immune haemolytic anaemia in the newborn?
A direct Coombs test (DCT) will be positive in haemolytic disease of the newborn.
Causes of Microcytic Anaemia (TAILS mnemonic)
T – Thalassaemia A – Anaemia of chronic disease I – Iron deficiency anaemia L – Lead poisoning S – Sideroblastic anaemia
Causes of Normocytic Anaemia (3As and 2Hs)
A – Acute blood loss A – Anaemia of Chronic Disease A – Aplastic Anaemia H – Haemolytic Anaemia H – Hypothyroidism
Name one cause of Megaloblastic Macrocytic Anaemia and one cause of Normoblastic Normocytic Anaemia
Megaloblastic anaemia is caused by:
- B12 deficiency
- Folate deficiency
Normoblastic macrocytic anaemia is caused by:
- Alcohol
- Reticulocytosis (usually from haemolytic anaemia or blood loss)
- Hypothyroidism
- Liver disease
- Drugs such as azathioprine
A high level of what immature red blood cells in the blood indicates active production of red blood cells to replace lost cells? This usually indicates the anaemia is due to haemolysis or blood loss.
Reticulocytes
What is the most common hereditary coagulopathy in humans?
Von Willebrand’s disease (vWD)
What are 2 main features of Von Willebrand’s disease (vWD)?
- Bleeding tendency from mucosa - eg, epistaxis, menorrhagia (consider in women with no other obvious cause).
- Spontaneous bleeding - eg, internal or joint bleeding (only in the most severe of cases).
- Blood clots during childbirth (rare).
What inheritance pattern does Von Willebrand’s disease (vWD) follow?
Autosomal dominant
What chromosome is affected in Von Willebrand’s disease (vWD)?
Chromosome 12
How is unconjugated bilirubin converted to conjugated bilirubin?
- Red blood cells contain unconjugated bilirubin.
- When they break down, they release unconjugated bilirubin into the blood.
- Unconjugated bilirubin is conjugated in the liver.
- Conjugated bilirubin is excreted in two ways: via the biliary system into the gastrointestinal tract and via the urine.
