Anaemia
Haematology
Short - The Haematological System
Anaemia = Hb or HCT <2.5th centile
Physiologic anaemia ~2mo
Haemaglobin = concentration of haemoglobin pigment in whole blood
Haematocrit = percent of blood occupied by RBCs (up in polycythemia/dehydration, down in anaemia)
Haematinic = RBC forming i.e. iron, B12, folate
Iron binds to protoporphyrins to produce heme
Less heme (↓MCH/hypochromic) > microcytosis (↓MCV) > ↑ RDW (anisocytosis)
They are more fragile > ↓RBC/Hb > Reticulocytosis
Film: above plus, elliptocytic
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Anaemia
Other cell lines abnormal
Isolated anaemia
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Hx drugs, diet
Ix
Film
Fe studies, therapeudic trial of iron
Hb EPG
B12 / folate
Bilirubin / LDH / Haptoglobin (binds released haem, for excretion, drops in haemolysis) to confirm haemolysis, DAT to differentiate
Cultures/viral studies
BMA/Trephine
Pb
G6PD quantative! (screen insensitive = false negatives)
Haptoglobin
Osmotic fragility: Spherocytosis
DAT: autoimmune haemolysis
TFTs
====
Infections
Fe overload: E.coli, Yersinia
Splenic disfunction: encapsulated organisms HiB, Strep pneumonia (NB causes HUS)
Hydroxyurea: stimulates HbF production
Short - The Haematological System
Anaemia = Hb or HCT <2.5th centile
Physiologic anaemia ~2mo
Haemaglobin = concentration of haemoglobin pigment in whole blood
Haematocrit = percent of blood occupied by RBCs (up in polycythemia/dehydration, down in anaemia)
Haematinic = RBC forming i.e. iron, B12, folate
Iron binds to protoporphyrins to produce heme
Less heme (↓MCH/hypochromic) > microcytosis (↓MCV) > ↑ RDW (anisocytosis)
They are more fragile > ↓RBC/Hb > Reticulocytosis
Film: above plus, elliptocytic
=====
Anaemia
Other cell lines abnormal
- High WC and Plt
- Infection (Film: toxic granulation, band cells, atypical lymphocytes)
- High WC
- Leukaemia (Film: blast)
- High Plt
- Fe deficiency
- Postsplenectomy (Film: Howell-Jolly Bodies)
- Low Plt
- Microangiopathic hemolytic anemia (schistocytes)
- Haemolytic uremic syndrome (anaemia, thrombocytopenia and AKI)
- (90% STEColi, 5% Compliment mediated, 4% Strep pneum, 1% other inc HIV)
- DIC
- TTP
- Haemolytic uremic syndrome (anaemia, thrombocytopenia and AKI)
- Evans syndrome
- Microangiopathic hemolytic anemia (schistocytes)
- Pancytopenia
- Leukaemia (Film: blasts) (cytogenetics)
- Myelosuppressive drugs/toxins
- Aplastic Anaemia (misnomer as all lines down, a/hypocellular marrow)
- Inherited (peak 2-5yo)
- Fanconi anaemia (short stature, thumb (so does DBA)/radius anomaly, café-au-lait skin lesions, malignancy, VACTERL-H) (Chromasomal breakage studies)
- Shwachman-Diamond syndrome usually neutropenia first (with pancreatic exocrine failure, and short stature)
- Dyskeratosis congenita: axial hyperpigmentation, nail dystrophy, mucosal leukoplakia...
- Amegakaryocytic thrombocytopenia: starts with low plt > develops AA, nothing else on presentation
- Acquired (present later)
- Idiopathic (80%)
- Post hepatitis (9%) ?viral not found
- Post-viral (7%)
- Drugs/toxins (4%)
- Inherited (peak 2-5yo)
- Hypersplenism
- Infection
- B12/Folate deficiency
Isolated anaemia
- Microcytic
- Fe deficiency (High RDW) (which can include chronic haemorrhage)
- Thalassaemia (Normal RDW) (alpha or gamma in neonate, beta later)
- Sideroblastic (Film: sideroblasts)
- (Chronic disease but usually normocytic)
- Normocytic
- Low retics
- Infection (Film: toxic granulation, band cells, atypical lymphocytes) inc Parvovirus in immunosuppressed
- Drugs
- Plumbism (Film: basophilic stippling)
- Acute haemorrhage
- Chronic disease
- Renal Disease
- Transient erythroblastopenia of childhood
- High retics
- Haemolysis
- Intrinsic (HS, G6PD, Sickle, Thal all confer Malaria protection and maps similar)
- Membranopathy
- Hereditary Spherocytosis (Film: spherocytes also seen in autoimmune haemolytic)
- Hereditary Eliptocytosis
- Enzymopathy
- G6PD deficiency (Heinz bodies sometimes but nonspecific) (60% illness, 40% drugs)
- PK deficiency
- Haemaglobinopathy
- Sickle-cell disease (can be macro) (Film: sickle cells)
- (Thalassemias are intrinsic haemolytic but microcytic)
- Membranopathy
- Extrinsic
- Autoimmune (can be macro) (DAT: pos, Film: spherocytosis also seen in HS)
- Warm-reactive AIHA (viruses)
- Cold-agglutinin disease (Mycoplasma/EBV)
- Paroxysmal cold haemaglobinuria
- Isoimmune (transfusion reaction)
- Mechanical
- Microangiopathic haemolytic anaemia (can be macro) (Film: schistocytes inc helmet cells)
- HUS
- TTP
- DIC
- Kasabach-Merritt syndrome
- Prosthetic heart valve
- Microangiopathic haemolytic anaemia (can be macro) (Film: schistocytes inc helmet cells)
- Chronic kidney / liver disease
- Autoimmune (can be macro) (DAT: pos, Film: spherocytosis also seen in HS)
- Combined intrinsic and extrinsic
- Paroxysmal nocturnal haematuria (Ham's acid sucrose lysis > now flow cytometry)
- Intrinsic (HS, G6PD, Sickle, Thal all confer Malaria protection and maps similar)
- No haemolysis
- Sub acute haemorrhage
- Haemolysis
- Low retics
- Macrocytic
- Drugs
- B12/Folate deficiency (Film: hypersegmented PMN)
- Sickle-cell (can be normocytic)
- Auto-immune haemolytic (can be normocytic) (Film: spherocytosis also seen in HS)
- Asplenia/Post-splenectomy (can be normocytic) (Film: Howell-Jolly bodies)
- Diamond-Blackfan (craniofacial, thumb anomalies (so does fanconi)
- Liver disease
- Hypothyroidism
=====
Hx drugs, diet
Ix
Film
Fe studies, therapeudic trial of iron
Hb EPG
B12 / folate
Bilirubin / LDH / Haptoglobin (binds released haem, for excretion, drops in haemolysis) to confirm haemolysis, DAT to differentiate
Cultures/viral studies
BMA/Trephine
Pb
G6PD quantative! (screen insensitive = false negatives)
Haptoglobin
Osmotic fragility: Spherocytosis
DAT: autoimmune haemolysis
TFTs
====
Infections
Fe overload: E.coli, Yersinia
Splenic disfunction: encapsulated organisms HiB, Strep pneumonia (NB causes HUS)
Hydroxyurea: stimulates HbF production