Haematology Flashcards

Question

polychromasia

Answer 1

disorder where there is an abnormally high number of immature red blood cells found in the bloodstream as a result of being prematurely released from the bone marrow during blood formation. These cells are often shades of grayish blue.

Answer 2

Lots of causes (see disorders of haemolysis) Most common are: ABO/resus incompatibility post viral hereditary spherocytosis HUS Can be associated with autoimmune phenomena (SLE) or immunodeficiency (SCID) ``` Can get: macrocytosis Raised reticulocytes Raised bili (more so in chronic) Raised LDH (break down) schistocytes polychromasia Need to do DAT to see if autoimmune ``` Treatment: - support with folic acid - avoid T/F as hard to provide compatible blood - Warm(rather than cold agglutinan) antibody mediated autoimmune haemolytic anaemia responds to steroids - treat underlying disease - if can't treat underlying disease AIHA may be refractory to Rx

Answer 3

Rare autoimmune disorder - autoimmune haemolytic anaemia (DAT +ve) - immune thrombocytopenia

Answer 4

Autosomal dominant Fh in 75% presentation heterogeneous deficiency or dysfunction of RCC cytoskeleton (spectrin, ankyrin or band 3) Splenomegaly almost always can get gallstones in chronic disease Low hb, raised retics spherocytes and polychromasia DAT negative if POSITIVE think SLE Raised bilirubin and LDH Ix: Osmotic fragility testing (thalasemia and hereditary spherocytosis) Eosin-5-maleimide (EMA) binding --> esp if no Fhx -LOW result confirms Dx Rx: Folic acid Splenectomy eventually (increased risk of encapsulated bacteria and VTE) Cholecystectomy if sx gallstones

Answer 5

-similar presentation to hereditary spherocytosis (except HS is DAT negative) -splenomegaly -Low hb, raised retics spherocytes and polychromasia DAT POSITIVE Raised bilirubin and LDH

Answer 6

is a fluorescent dye that reacts to bind covalently to band 3 protein in the red cell membrane. Analysis by flow cytometry measures the fluorescent intensity of labelled intact red cells used for dx of hereditary spherocytosis LOW result confirms dx

Answer 7

RBC which contain a nucleus Look blue/purple --> similar to monocytes Are big, immature rcc only present in neonates or fetuses normally Abnormally means high demand on bone marrow --> haemolytic anaemia --> haemolytic disease of the new born

Answer 8

ABO/Resus D DAT positive Spherocytes Nucleated RBC Low Hb RCC agglutination on film

Answer 9

round shaped rcc | present in all haemolytic anaemia to a degree

Answer 10

process that occurs if an antigen is mixed with its corresponding antibody called isoagglutinin. This term is commonly used in blood grouping . This occurs in biology in three main examples: The clumping of cells such as bacteria or red blood cells in the presence of an antibody or complement

Answer 11

Clumping (agglutination) of red blood cells is frequently caused by cold agglutinins ``` causes: Spurious macrocytosis intravascular haemolysis C3 coating on RBC Post-viral Mycoplasma infection ```

Answer 12

Cold agglutinins are autoantibodies produced by a person's immune system that mistakenly target red blood cells (RBCs). They cause RBCs to clump together when a person is exposed to cold temperatures and increase the likelihood that the affected RBCs will be destroyed by the body

Answer 13

fragmented blood cells aka helmet cells caused by mechanical haemolysis -HUS, DIC, TTP, cardiac valves, ECMO

Answer 14

Autosomal recessive Defect in ADAMTS13 gene ADAMTS13 gene processes a large protein called von Willebrand factor. It helps to prevent uneccesary clotting Usually occurs in infancy and childhood but can occur when a woman is pregnant Clotting in small blood vessels fever and puprura/petechiae ``` Haemolytic anaemia - schistocytes Low Hb, Low Plt, Raised LDH and bilirubin Raised creatinine/proteinuria Coags normal ``` Rx: plasma exchange +/- immunosuppression

Answer 15

Mutation of HBB gene on chromo 11 Autosomal recessive No beta chains Jaundice, fatigue, frotal bossing, gallstones, splenomegaly, maxillary hyperplaisa, dental malocclusion ``` Raised HbA2 (because can't make B chains) Mildly raised HbF ``` Ix: Haemaglobin electrophoresis Hb A2 and HbF measurement Antenatal: CVS, sequence B globulin chains Rx: 1. T/F dependent --> TF if <90. Hypertransfuse aim Hb>100 pre next TF 2. iron chelation (as risk of iron overload). 3 drugs: - deferoxamine --> SC over 8 hours, feel unwell. increased risk of cataracts - Deferipone --> increased risk agranulocytosis - Deferasirox --> increased risk of renal impairment 3. Transplant --> matched sibling. done first 10-12 years ``` Risk of Fe toxicity: Diabetes arthritis heart depositions--> arrythymias, CHF cirrhosis of liver ```

Answer 16

AR Defect chromo 16p Jaundice, fatigue, frotal bossing, gallstones, splenomegaly Haemaglobin electrophoresis - beta chains in aduts - gamma chains in neonates Haemoglobin BARTS = only gamma chains if no HA2 (results in death in neonate as poor affinity 02

Answer 17

``` 1:100,000 assoc with minor infections less than 4 years old (90% occur <14 months) +ve anti-neutrophil autoantibodies 95% remission 7-24 motnhs ```

Answer 18

less severe if also inherited a thalassemia trait abnormality in B chain SS Issues are vasoccclusive crises, aplastic, haemolytic and sequestration ``` Rx: splenectomy Rare TF Hydroxyurea ameliorates disease by increasing HbF Risk of proliferative retinopathy ```

Answer 19

AR Shwachman-Diamond syndrome is the second most common cause of inherited pancreatic insufficiency after cystic fibrosis and the third most common inherited bone marrow failure syndrome after Fanconi anemia and Diamond-Blackfan anemia. Exocrine pancreatic insufficiency metaphyseal abnorm may progress to marrow aplasia Neutropenia/neutrophil migration defect (can have cyclical neutropenia--> •Recurrent bacterial infections of the upper respiratory tract, otitis media, sinusitis, pneumonia, osteomyelitis, bacteremia, skin infections, aphthous stomatitis, fungal dermatitis, and paronychia are common high risk AML with GCSF

Answer 20

signficant infection hx - pneumonia, abscess, gingivitis elevated monocytes or eosinophils (+ low neu) Multigene disorder >50% mutation in neurtrophil elastane gene (ELANE) ``` Kostman's syndrome --> form of CN -assoc with cognitive defects and seizures HAX1 mutation - early onset and severe infections -may need high levels gcsf ```

Answer 21

promotes release of vWF through releasing endogenous factor VIII Used in treatment of mild haemophilia A and thrombocytopenia and VWD

Answer 22

X-linked recessive - atopic dermatitis - thrombocytopenic purpura - small defective plts - high infection risk

Answer 23

AR -very rarely is X-linked -defect in FA pathway --> important in DNA repair --> defect results in abnormal cell build-up - rapidly dividing cells affected esp bone marrow = bone marrow failure with pancytopenia - Most common congenital bone marrow failure syndrome (2nd is Diamond black, 3rd is Schwachmann diamond) - Type of chromosomal breakage syndrome (along with telangectasia ataxia) -Significant increased risk of leukaemia esp AML -significant increased risk of head/CNS, neck, GI, genital =10-30% of children with this will get at least 1 Dysmorphic features: - ABNORMAL THUMBS - ABSENT RADII - cafe au lai spots - strabismus - low set ears - hearing loss - short - triangular facies, - microcephaly - -abnormal kidneys, decreased fertility Ix: Chromosomal breakage studies

Answer 24

Splenic sequestration occurs primarily in infants, as early as five weeks old. Approximately 30% children with sickle cell anaemia will have splenic sequestration. This presents as engorgement of the spleen, a rapid increase spleen size, hypovolaemia and a decreased haemoglobin. Reticulocytosis may be present It is often precipitated by URTI, bacteraemia, viral infection. The treatment is to stabilise haemodynamically, and then carry out a prophylactic splenectomy after the first event.

Answer 25

Von Willebrand disease patients often have normal clotting tests, and if they are abnormal usually have a prolonged APTT AND bleeding time.

Answer 26

Aspirin would be expected to produce a prolonged bleeding time.

Answer 27

-Usually AD Congenital erythroid aplasia (within the bone marrow)that usually presents in infancy (can present later) - different compared to Schwachman diamond syndrome and Fanconi which are congenital bone marrow failure syndromes with true pancytopenia - Profound megaloblastic anaemia - May have low WCC and Plt but not a profound pancytopenia - Increased risk of AML -Approximately half of individuals with Diamond-Blackfan anemia have physical abnormalities such as microcephaly, low frontal hairline, hypertelorism, ptosis broad, flat bridge of the nose,small, low-set ears, microngathia Ix: - Profound anaemia +/- low plts/wcc - Absent reticulocytosis - Absent erythroid progenitors in the BMA, bland film nil significant poikilocytosis