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Anaemia. Anne Mitchell. ANAEMIA. Reduction in the red cell mass or Hb < 2 standard deviations below the mean cardiovascular compromise. Evaluation of the pale child -. Age nutritional anaemia disorder of Hb synthesis or structure Duration of anaemia blood loss Associated features Sex
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Anaemia Anne Mitchell
ANAEMIA • Reduction in the red cell mass or Hb • < 2 standard deviations below the mean • cardiovascular compromise
Evaluation of the pale child - • Age • nutritional anaemia • disorder of Hb synthesis or structure • Duration of anaemia • blood loss • Associated features • Sex • X-linked disorders e.g..G6PD deficiency • Ethnic background • thalassaemia • sickle cell disease • Neonatal history • prematurity • hyperbilirubinaemia
Bowel habits • Diet • iron, B12, folate intake • Drugs • oxidant drugs, phenytoin • Infection • aplastic crisis • Inheritance • anaemia, gall stones, jaundice, splenectomy
Examination of the pale child - • Skin • jaundice • petechiae • hyperpigmentation • haemangiomas • ulcers • Face • frontal bossing • Eyes • cataracts • microcornea • retinal haemorrhages • oedema of the eyelids • vitreous haemorrhages, retinal microaneurysms, • Mouth • glossitis
Hands • hypoplasia of the thenar eminence • triphalyngeal thumb • Liver • Spleen • Lymph nodes • Abdominal masses • Chest • shield chest
Investigations - • FBC and film • Hb • Age Hb MCV • 0.5 - 1.9 12.5 77 • 2 - 4 12.5 79 • 5 - 7 13.0 81 • 8 - 11 13.5 83 • MCV • microcytic • macrocytic • normocytic • MCHC • hypochromic • normochromic
White cell count • total and differential counts • Platelet count • Reticulocyte count • Coombs test • Hb electrophoresis • Ferritin, serum iron, TIBC, B12 and folate • bilirubin, LDH, haptoglobin • G6PD screen, osmotic fragility test • Bone marrow aspirate/trephine
MICROCYTIC HYPOCHROMIC ANAEMIA • Iron deficiency • decreased serum iron • increased TIBC • decreased transferrin saturation • ferritin < 10 • Chronic disease • decreased serum iron • decreased TIBC • decreased transferrin saturation • ferritin normal or high
MICROCYTIC HYPOCHROMIC ANAEMIA • Thalassaemia • increased serum iron • decreased TIBC • increased transferrin saturation • increased ferritin • MACROCYTIC ANAEMIA • Neonates • Reticulocytosis • Liver disease • Megaloblastic anaemia
TRANSIENT ERYTHROBLASTOPENIA OF CHILDHOOD • Erythroid stem cell failure • Epidemiology • occurs between 1 and 3 years of age • male > female • Presentation • gradual onset of pallor • preceding viral illness
Laboratory findings • anaemia (Hb as low as 2.2 g/dL) • decreased reticulocyte counts • may have mild neutropenia and thrombocytopenia • normal MCV and MCHC • normal HbF • Causal factors - • viruses e.g.. parvovirus, EBV, CMV • drugs e.g. penicillin, aspirin, valproate, phenytoin • Treatment • observation • transfuse if cardiovascular compromise
AUTOIMMUNE HAEMOLYTIC ANAEMIA • Coombs positive haemolytic anaemia • Epidemiology • following infection • auto-immune disease • usually < 5 years old • Clinical presentation • acute onset of pallor • splenomegaly • jaundice • cardiac failure • may be shocked at presentation
Laboratory findings • Coombs positive anaemia • IgG warm antibodies • post infectious e.g. hepatitis, CMV • idiopathic • IgM cold antibodies • post infectious e.g. mycoplasma, EBV • Donath-Landsteiner biphasic antibodies • post infectious e.g. measles, mumps, varicella, infectious mononucleosis • reticulocytosis • hyperbilirubinaemia • haemoglobinuria • decreased haptoglobins
Treatment • Blood transfusion • use least incompatible blood • give slowly • give IV fluids • if IgM antibody present warm blood • Steroids • prednisolone at 2mg/kg/day for IgG antibody • taper slowly • Splenectomy • occasionally only means of decreasing haemolysis
APLASTIC ANAEMIA • Bone marrow failure • leukopenia • thrombocytopenia • low reticulocyte count • poor bone marrow cellularity • Epidemiology • about 2 children per million per year • more common in Asia • Presentation • bleeding • infection
Causal factors - • Drugs • chloramphenicol • NSAIDs, carbamezepine, cimetidine • Toxins • benzene, aromatic hydrocarbons, ionizing radiation • Infections • parvovirus B19 • EBV • CMV • HIV • rubella, mumps, measles, varicella, influenza A
Laboratory findings • anaemia - often macrocytic • increased HbF and “i” antigen • thrombocytopenia • neutropenia • decreased reticulocyte count • increased erythropoeitin levels • bone marrow • hypocellular • megaloblastosis • marrow lymphocytes >70% poor prognosis
Prognosis • mortality rate in first 6 months is 50% • Spontaneous recovery may occur • Treatment • Supportive care • minimize use of blood products • HLA matched single donor platelets preferable • use filtered red cells • tranexamic acid or aminocaproic acid for mucosal bleeding
Bone marrow transplantation • choice of treatment if matched sibling available • 90% survival with HLA matched sibling BMT • 45% survival with matched unrelated BMT • children NOT receiving prior transfusion do better • Immunosuppression • anti-thymocyte globulin (ATG) or ant-lymphocyte globulin (ALG) • response rate of 45% • response occurs within 3 months • cyclosporin A • high dose steroids • increased incidence of myelodysplasia, leukaemia, other malignant diseases
Growth factors • may be some response to GCSF • Androgens • stimulate erythroid stem cells and increase erythropoeitin • not clear whether they are beneficial
FANCONI’S ANAEMIA • Bone marrow failure • thrombocytopenia • neutropenia and anaemia • Epidemiology • usually diagnosed at about 8 years of age • male > female • Presentation • congenital abnormalities • infection • bleeding
Laboratory findings • pancytopenia • increased HbF and “i” antigen • mitomycin C stress test • spontaneous chromosome breaks, translocations, exchanges • pre-natal testing is now available • Physical examination • skin involvement • hyperpigmentation, café au lait spots, large freckles • poor growth • anomalies of the upper limbs • absent or hypoplastic thumbs, absent or hypoplastic radii, hypoplasia of the thenar eminence, abnormal fingers • renal abnormalities • ectopic , horseshoe or dysplastic kidneys,
Prognosis • projected median survival is 25 years • risk of malignancy, especially in females • Treatment • Androgens • 75% show some initial response • Bone marrow transplantation • curative • conditioning regimen may cause severe toxicity
Complications • Leukaemia • 10% • usually myeloid leukaemia • Preleukaemia/myelodysplasia • clonal cytogenetic abnormalities • Cancer • 5% develop cancer • Liver disease • 5% develop liver disease
BLACKFAN-DIAMOND SYNDROME • Erythroid stem cell failure • Epidemiology • 90% occur under the age of 1 year • Male = female • autosomal dominant, autososmal recessive • 75% new mutations • Presentation • usually < 1 year • pallor • heart failure
Physical findings • About 25% children have abnormal physical appearance • blond, snub nose • cleft lip/palate • radial ray anomalies • Laboratory findings • macrocytic anaemia • increased HbF and “i” antigen • decreased/absent reticulocytes • may have increased erythrocyte adenosine deaminase
Treatment • Spontaneous remission • 15% to 20% may have a spontaneous remission • Blood transfusion • leukocyte depleted packed red cells • 3 to 6 weekly • require desferrioxamine chelation therapy as soon as iron stores are increased • Corticosteroids • 2mg/kg/day then taper • 60% become steroid dependant • trial of high dose steroids if poor response
Bone marrow transplantation • more successful in young relatively untransfused patients • Complications • possible increased incidence of leukaemia
IRON DEFICIENCY ANAEMIA • Defect of cytoplasmic maturation • Epidemiology • 6 to 36 months • premature infants • adolescents • Presentation • fatigue, decreased exercise tolerance, pallor • altered behaviour • pica, geophagia
Laboratory findings • anaemia • microcytic • hypochromic • ferritin < 10 µg/L • transferrin saturation < 16% • TIBC > 72 µmol/L • Causal factors - • dietary • cow’s milk • blood loss • Meckel’s diverticulum • inflammatory bowel disease • menorrhagia
Treatment • Diet • education • Iron supplementation • 6mg/kg/day of elemental iron • IM iron • deep injection • staining • IV iron • anaphylaxis • sucrose formulations
Follow Up • expect reticulocyte response in 5 to 10 days • recurrent and unresponsive to treatment requires further investigation
MEGALOBLASTIC ANAEMIA • Defective nuclear maturation • FOLATE DEFICIENCY • Epidemiology • premature infants • pregnancy • haemolysis • goats milk • coeliac disease • methotrexate, co-trimoxazole
Presentation • may be asymptomatic • Laboratory features • low serum folate • low red cell folate < 140ng/ml • hypersegmentation of neutrophil nuclei (> 4 lobes) • macrocytic anaemia • increased RDW • megaloblastic bone marrow
Treatment • folate supplementation 0.5mg/day • reticulocyte response in 10 days
VITAMIN B12 DEFICIENCY • Epidemiology • dietary • strict vegetarian • inadequate absorption • lack of intrinsic factor (congenital or juvenile) • surgical removal of terminal ileum • transcobalamin II deficiency • rarely evident until late infancy • Presentation • developmental delay • neuropathy • posterior column signs, confusion, seizures
Laboratory findings • hypersegmented neutrophils • serum vitamin B12 < 100pg/ml • thrombocytopenia • neutropenia • megaloblastic bone marrow • Schilling test • increased excretion of urinary methylmalonic acid • Treatment • 25 to 100µg vitamin B12 daily to monthly
PHYSIOLOGIC CLASSIFICATION OF ANAEMIA • Disorders of red cell production • 1. Pluripotential stem cell failure • Aplastic anaemia • congenital • Fanconi’s anaemia • acquired • 2. Marrow replacement • Leukaemia, solid tumour • Myelofibrosis
Disorders of red cell production • 3. Erythroid stem cell failure • congenital • Diamond-Blackfan anaemia • acquired • transient erythroblastopenia of childhood • 4. Defects of cytoplasmic maturation • Iron deficiency • Thalassaemia • Lead poisoning • Sideroblastic anaemia
Disorders of red cell production • 5. Defects of nuclear maturation • Vitamin B12 deficiency • Folate deficiency • Dyserythropoeitic anaemias • Blood loss
Haemolytic anaemia • Hereditary • membrane abnormalities e.g. hereditary spherocytosis • Hb abnormalities e.g. unstable Hb • metabolic abnormalities e.g. G6PD deficiency, pyruvate kinase deficiency • Acquired • immune mediated - isoimmune, autoimmune • toxins