Anaemia Flashcards
Describe the normal Hb changes in children
Hb normally falls during the first months of life, reaching a low point at 6-8 weeks old, and spontaneously coming back up by 4 months. Infants are usually born with adequate iron stores to last the first 3-4 months of life, so true iron-deficiency below 4 months, in the absence of blood loss (e.g. gastrointestinal), is rare.
What are the causes of anaemia in children
Microcytic: IDA, thalassaemia, SCD
Normocytic: Haemolytic anaemia, SCD, aplastic anaemia, ACD
Macrocytic: Vit B12 or folate deficiency
What are the causes of iron deficiency anaemia
Bleeding e.g. menstrual/GI
Increased use e.g. growth/pregnancy, malignancy
Dietary deficiency e.g. vegetarian
Malabsorption e.g. coeliac, IBD
Adolescent pregnancy
Early cow’s milk introduction
Lack of delayed cord clamping at birth
What are the sources of iron in neonates
Breast milk (50%)
Formula
Cow’s milk (poor source)
Solids at weaning
Iron in breast milk is well absorbed but the iron in artificial feeds or cow’s milk is less so
What are the signs and symptoms of iron deficiency anaemia
Lethargy/fatigue/difficulty concentrating
Light-headedness/dizziness
SOB
Irritability/poor feeding
Pallor
Brittle nails and hair
Koilonychia
Cheilitis, angular stomatitis
Glossitis
What investigations should be done for iron deficiency in children
FBC: microcytic anaemia
Iron studies:
- Serum iron - Reduced in IDA
- Iron binding capacity - Raised in IDA
- Serum ferritin - Reduced in IDA, raised in sideroblastic
- Transferrin - Reduce in IDA
Film: microcytic, hypochromic RBC, anisocytosis, poikilocytosis, target cells, pencil cells, elliptocytes
What is the management plan for iron deficiency in children
- exclude underlying causes
- Diet and advice (green leafy vegetables, vit C, avoid milk/tea/high fibre)
- Iron supplementation for 3 months (Sytron)
± Oral folic acid if the cause is not known (can exacerbate B12 deficiency symptoms if given)
± IM hydroxocobalamin for B12 deficiency
Second line: parenteral iron
What are the complications and prognosis of anaemia in children
Preterm or LBW (Low Birth Weight) baby
Postpartum depression
Child with developmental delays
Spina bifida
Susceptibility to infections
Physical weakness
Postpartum haemorrhage
Increased risk of neonatal iron deficiency
Good prognosis
Define thalassaemia
Group of genetic disorders characterised by a defect in and reduced globin chain synthesis
Alpha or beta
What is the aetiology of alpha thalassaemia and what are the types
Alpha-globin gene mutation on Chr 16
1-2 gene deletion: Microcytic hypochromic red cells, no anaemia - Alpha (+)
3 gene deletion: Microcytic hypochromic anaemia, splenomegaly (Hb H)
4 gene deletion: Hb Barts and intrauterine death (hydrops fetalis) - Alpha (0)
What is the aetiology of beta thalassaemia and what are the types
Beta-globin gene mutation on Chr 11
Autosomal recessive inheritance
Trait → Carrier, asymptomatic, mild microcytic anaemia, raised RBC
HbE beta
Thalassaemia Intermedia → Mild defect in synthesis (+ forms instead of 0) → reduced alpha chains or increased gamma chains
Thalassaemia Major → No globin production, homozygous, both copies affected, B0/B+
What are the symptoms of thalassaemia
Anaemia: Fatigue, Pallor, Dizziness, SOB
Alpha
Alpha (+): asymptomatic
Alpha HbH: variable, anaemia symptoms, jaundice, gallstone symptoms
Beta
- Presents at 3-6 months (due to switch form gamma (HbF) to beta globin (HbA) synthesis)
- Failure to thrive and prone to infections
- Anaemia → heart failure, growth retardation, Dyspnoea, fatigue
- Erythropoietic drive (extra-medullary haematopoiesis)→ bone expansion, hepatomegaly (facial and small bones), splenomegaly
- Iron overload → heart failure, gonadal failure
What are the signs of thalassaemia on examination
Facial dysmorphism: skull bossing, maxillary overgrowth
Poor growth
Mild jaundice
Pallor
Hepatosplenomegaly
What investigations should be done for thalassaemia
Heel prick at 5 days
Bloods:
- FBC: microcytic anaemia
- Reticulocytes: elevated
- Iron studies: normal
- Blood film: microcytic, hypochromic RBCs, poikilocytosis, Howell Jolly bodies (nucleated RBCs), Target cells
- Beta major: Alpha globin precipitates and Pappenheimer bodies
- Perl’s stain: inky blue granules (haemosiderine/pappenheimer bodies)
Hb electrophoresis: Raised HbA2 and HbF, Absent or reduced HbA
LFTs: elevated total/unconjug bilirubin
Bone marrow: erythroid hyperplasia, hypercellular
What is the management for thalassaemia
Regular blood transfusions (2-3 units per month)
Iron chelation therapy + audiology and opthalmology screening
Splenectomy + Prophylaxis (immunisation and Abx)
Supportive medical care
Hormone therapy
Hydroxyurea to boost HbF
Bone marrow transplant
± Accurate diagnosis and family counselling
What are the complications of thalassaemia
Cholelithiasis and biliary sepsis (gall stone formation)
Cardiac failure (leading cause of death)
Endocrinopathies
Liver failure
Increased risk of infection
What is the prognosis for thalassaemia
Alpha
Trait: asymptomatic → genetic counselling
HbH: normal life
Hb Bart: survival into childhood, risk of congenital anomalies, neuro impairment, lifelong transfusion + support
Beta
Intermedia: cosmetic changes
Major: fatal untreated, near-normal if treated
What are the causes of vitamin B12 deficiency
Dietary (e.g. vegans) - B12 found in meat and dairy
Malabsorption:
- Stomach (lack of intrinsic factor which is produced by gastric parietal cells) → Pernicious anaemia, post gastrectomy
- Terminal ileum (absorption) due to ileal resection, Crohn’s disease, bacterial overgrowth, tropical sprue and tapeworms.
What are the clinical features of B12 deficiency
Mouth: Glossitis, angular cheilosis
Neuropsychiatric: Irritability, depression, psychosis, dementia.
Neurological: Paraesthesiae, peripheral neuropathy (loss of vibration and proprioception first, absent ankle reflex, spastic paraperesis, subacute combined degeneration of spinal
cord)
What is pernicious anaemia and what investigations should be done for diagnosis
Autoimmune atrophic gastritis → achlorhydria and lack of gastric intrinsic factor
Most common cause of a macrocytic anaemia in Western countries (Usually >40yrs)
Specific tests: Parietal cell antibodies (90%), Intrinsic factor antibodies (50%), Schilling qtest (outdated)
What are the causes of folate deficiency
Poor diet
Increased demand: pregnancy or ↑ cell turnover (haemolysis, malignancy, inflammatory disease and renal dialysis).
Malabsorption: coeliac disease, tropical sprue.
Drugs: alcohol, anti-epileptics (phenytoin), methotrexate, trimethoprim
What is the management for B12 and folate deficiencies
B12: Replenish stores with IM hydroxocobalamin (B12) with 6 injections over 2 weeks. (if pernicious anaemia → 3-monthly IM injection)
Folate: oral folic acid (B12 is checked and replaced prior to folic acid otherwise folic acid may exacerbate the neuropathy of B12 deficiency)
What are the complications of B12 deficiency
Subacute degeneration of the cord (Dorsla columns)
S/S: tingling, numbness, weakness, visual impairment, change in mental state, bilateral paresis/paralysis
