Haematology Flashcards
What are the Hb types in normal children?
At birth HbF, HbA, HbA2
HbF lowers at 6 months
At this point Hbpathies will manifest
How do cell counts change with age?
At birth (Hb 14-21, WBC 10-25, MCV 100-130, volume 80 mL/kg, 100 in preterm) 2 months (Hb 10, WBC 6-18, MCV 80-100) Preterms at 2 months (Hb 6-9)
What is anemia?
Neonat <14
Infant <10
Child <11
What are the causes of anemia?
Reduced production -Ineffective erythropoiesis (IDA, Folic, ACD, CKD, Pb, MDS) -Red cell aplasia (Parvo B19, congenital, AA, ALL) Haemolysis -Membranopathy (HS) -Enzymopathy (G6PD) -Hbpathy (Thal, SCD) -Immune (HDN, AIHA) Bleeding -Malena (mucked) bleeding diatheses (vWD)
How to investigate anemia?
FBC - low Hb, MCV - low or high Blood film Retic count - low or normal SBR S Ferritin HPLC Parvovirus serology Bone marrow aspirate
How to differentiate HPLC?
SCD - HbS, no HbA
beta major - only HbA
beta minor - high HbA2
What are the causes of IDA?
Diet (<8 mg/day)
Malabsoprtion
Blood loss
What are the dietary sources of iron for infants?
Breast milk (low gross but 50% bioavailability ) Formula milk (high gross) Cow milk (high cross but 10% bioavailability) Complementary food (high in vit c low in tannin and phytates)
What are the features of IDA?
Tiredness, lethargy, pallor, pica, behavioural and intellectual oddities
How to manage IDA?
Classify severity Supply 1 mg/kg/day elemental iron Diet change, feeding habit change Non teeth staining sodium iron edetate Continue for 3 months after normal Hb
What type of anemia does Parvo B19 cause?
Red cell aplasia in children already having inherited haemolytic disease
What is the mechanism of haemolytic anemia?
Red cell life span is 120 days
Bon marrow production rate < destruction rate
What are the features of haemolytic anemia?
Anemia HSM Unconjugated bilirubin Urine urobilinogen Raised retic count (polychromasia) Abnormal cells on bloodfilm DAT positive in AIHA
What are the features of HS?
AD, 25% no FHx Spectrin, Ankyrin, Band 3 mutations Spheroidal non deformable RBC Extravascular hemolysis in spleen Jaundice and anemia Sudden crisis from B19 Gallstones and splenomegaly Blood film + osmotic fragility DAT to rule out AIHA Give oral folic acid
What are the feature of G6PD?
G6PD prevents oxidative damage to RBC X linked recessive Neonatal jaundice Acute hemolytic anemia from infection, fava, quinines Dark urine, jaundice, pallor No need to transfuse
What are the features of SCD?
Beta globin mutation valine replaces glutamine HbSS, HbSC both have no HbA Asymptomatic sickle trait Sickling from HbS polymers Anemia and jaundice Hyposplenism causing infection risk Vasoocclusive dactylitis, desaturation Acute anemia from Parvo B19 Priapism Splenomegaly Stoke, short stature, delayed puberty, adenoid hypertrophy heart failure and cardiomegaly Pigment stones AKI CKD Leg ulcers Mx Vaccinate and penicillin prophylaxis life long Oral folic acid Avoid stressors, prevent cold and dehydration Exchange transfusion and analgesia Early death
What are the 5 components of haemostasis?
Coagulation factors Platelets Endothelium Coagulation inhibitors Fibrinolytics
What are the factors that limit coagulation?
NO PGI2 Antithrombin Protein S Thrombomodulin
What are the 2 coagulation pathways?
Extrinsic (TF>Ca>VII>X>V>Thrombin>Fibrin+XIII)
Intrinsic (XII>XI>IX>VIII>X+V>Thrombin>Fibrin
When do bleeding disorders present?
Neonate (ICH, circumcision bleeds)
Toddler (Hemophilias)
Adolescent (menorrhagia in vWD)
How do bleeding orders present?
Mucosal (platelet, vWD)
Joints (Hemophilias)
How to investigate bleeding disorders?
FBC with BPx BT PT APTT TT LFT
What are the features of haemophilia?
Commonest inherited bleeding disorders X linked recessive A = VIII, B=IX, A is 6 times more common Rx = raise factor by 100% or 30%, maintain 50% for 2 weeks Avoid IM, NSAIDs, Aspirin DDAVP for mild A only, NOT for B
What are the acquired coagulation disorders?
Haemorrhagic disorders of newborn (vit K deficiency)
Liver disease
ITP
