Haematology Flashcards
What are the characteristic blood test results in iron-deficiency anaemia?
Microcytic anaemia (low MCV), low ferritin (however an acute phase reactant so can’t always rely on), raised transferrin, raised total iron binding capacity.
What are the most common causes of iron-deficiency anaemia in different age categories?
Menstruating women - 2ndary to menstruation
Men + post-menopausal women - GI bleeding
Pre-school children have the greatest prevalence of iron-deficiency anaemia - increased iron requirement during growth. For similar reasons, iron-deficiency anaemia also becomes more prevalent during pregnancy.
Iron absorption is impaired in coeliac disease so consider serological testing if unexplained (total IgA and IgA TTG / tissue transglutaminase)
What are the main causes of micro, normo and macrocytic anaemia?
Microcytic: Iron-deficiency, Beta thalassaemia (inherited, absent or decreased synthesis of beta-globin chain, depending on whether homo or heterozygous can be anywhere on the spectrum from transfusion-dependent to asymptomatic. Excess iron replacement can harm)
Normocytic: anaemia of chronic disease, EPO deficiency (eg in chronic kidney disease), bone marrow insufficiency
Macrocytic: Folate or Vitamin B12 deficiency, Haemolytic anaemia.
What are common examples of intravascular versus extravascular haemolysis?
Intravascular haemolysis: microangiopathic haemolytic anaemia (breakdown in small blood vessels and includes DIC, HELLP syndrome, Haemolytic uraemic syndrome (following E.coli GI infection), ABO incomptability, Rhesus disease. Extravascular haemolysis (breakdown of RBCs in spleen + liver): divided into those with normal RCCs (malaria, autoimmune haemolytic anaemia) and deformed RCCs (sickle cell anaemia, thalasaemia, G6PD deficiency)
What is the characteristic presentation of polycythaemia vera?
- Itchiness (especially after baths/showers)
- Tingling / burning / numbness in limbs and hands/feet
- Splenomegaly
- ^ Hb on FBC
= neoplastic expansion of haemtopoetic cells in the bone marrow. Peak incidence is in people in their 60’s.
2-8% will progress into myelopfibrosis (malignant) and 1-3% will progess into acute myeloid leukaemia
What is the genetic mutation associated with most cases of polycythaemia vera?
V617F mutation on JAK2
What is the 1st line management of polycythaemia vera?
Repeat blood tests every 3-6 months and if haematocrit > 0.45 on 2 or more occasions then refer to haematology for a venesection programme.
What is the inheritance pattern of haemophilia A and B?
X-linked recessive
What is NICE guidance on management of a supected DVT
Clinical suspicion of a DVT = calculate a Wells Score.
If Wells score 2 or more = DVT likely = get a doppler USS within 4 hours OR if not possible then take a D-Dimer, commence anticoagulation and arrange USS within 24 hrs.
If scan is negative then take a D-Dimer (if haven’t already) -> if scan and d-dimer negative = v unlikely. if scan neg and D-Dimer positive then offer repeat USS in 6-8 days
If Wells score 0 or 1 - DVT unlikely = D-Dimer within 4 hours OR if not possible then commence anticoagulation and arrange D-Dimer within 24 hours. If D-Dimer is positive then USS within 4 hours / or commence anticoagulation and USS within 24 hrs.
Causes of microcytic anaemia?
1) Iron deficiency -> low iron, low ferritin, high TIBC
2) Thalassaemia -? high iron + ferritin, low TIBC
What is the typical presentation of hereditary spherocystosis?
Inherited haemolytic anaemia
= macrocytic anaemia, ^ reticulocytes, ^ LDH, ^ urinary urobilinogen, ^ mean corpuscular haemoglobin concentration, decreased haptoglobin
What antibody is associated with pernicious anaemia
Intrinsic factor antibodies
- > Vit b12 deficiency
- > macrocytic anaemia
Typical presentation of beta thalassaemia major?
in CHILDHOOD with failure to thrive and severe microcytic anaemia with high iron/ferritin + frontal bossing (=bossing in the skull) + hepatosplenomegaly
Tx = Desferrioxamine (iron-binder) + lifelong blood transfusions
Typical presentation of infective mononucleosis?
Sore throat symptoms + cervical lymphadenopathy + splenomegaly
Dx = monospot test -> heterophile antibodies
Causative agent = EPV
Which chromosomal abnormality is associated with chronic myeloid leukaemia?
Philadelphia chromosome (chromsome 9 and 22 translocation) = presents INSIDIOUSLY with MASSIVELY raised WCC count (>100)
Which clotting factor is deficient in haemophilia A?
Factor 8 (A for 8!!)
Which clotting factor is deficient in haemophilia B?
Factor 9
What investigations are suggestive of haemophilia?
^ APTT + factor 8 / 9 deficiency on assay
Desmopressin = can ^ factor 8 levels in haemophilia A
How should an abnormal INR be managed in a patient on warfarin?
If major bleeding on warfarin -> stop warfarin, give IV Vit K + IV prothrombin complex concentrate (or FFP if PCC not available)
If minor bleeding + INR > 5 -> stop warfarin + give IV Vitamin K. Resume warfarin when INR <5.
If no bleeding + INR >8 = stop warfarin + give oral Vitamin K
If no bleeding + INR 5-8 = suspend warfarin for 1-2 doses and then reduce ongoing maintenance dose
In what conditions are target cells seen on blood film?
iron deficiency anaema
Thalassaemia
Liver disease
after splenectomy
What condition shows Auer rods on bone marrow biopsy?
AML (acute myeloid leukaemia)
When are Rouleux formations seen on blood film?
Rouleux formations = clumps of red cells, seen in conditions associated with a high CRP/ESR
- infection
- Chronic inlammation / autoimmune disorders
- Myeloma
When are Heinz bodies seen within RBCs on blood film?
Sub-types of haemolytic anaemia associated with toxin exposure eg G6PDD deficiency after exposed to a precipitant
In what condition are drepanocytes seen in the blood film?
Sickle cell anaemia
drepanocytes = sickled cells
In what condition are reed-sternberg cells seen in blood film?
Hodgkin lymphoma (reed sternberg cells = large malignant lymph cells with more than one nucleus)
What is the most common cancer of childhood?
ALL -> acute lymphoblastic leukaemia
-> pancytopenia with immature blast cells, relatively rapid onset of symptoms over weeks
Better cure rate in children than adults
What is the most common leukaemia in adulthood?
AML
Auer rods on blood film
Associated with prev chemotherapy
What treatment should a pregnant lady with antiphospholipid syndrome be on?
Aspirin + LMWH
What antibiotic prophylaxis is given to patients with prev splenectomy?
Penicillin V
covers for encapsulated organisms -> strep pneumoniae + h.influenzae
What is the typical presentation of chronic lymphocytic leukaemia (CLL)
DISEASE OF THE ELDERLY, VERY GRADUAL PROGRESSION. See SMEAR CELLS on blood film
lymphadenopathy with slowly enlarging lymph nodes
Can transform to a more aggresive version (Richter’s syndrome)
Typical presentation of myelofibrosis?
Cancer involving scarring of bone marrow -> severe anaemia + teardrop cells on film (due to bone marrow infiltration) + hepatosplenomegaly as liver + spleen take over haemtopoeisis
10% risk of progression to AML
Typical presentation of G6PDD deficiency?
X-linked recessive enzyme defect common in those from mediteranean
Precipitants (fava beans, ciprofloxacin, thiazide diuretics) can -> haemolytic crisis (see Heinz bodies)
Leukaemias versus lymphomas?
Lymphoma = cancer of mature lymphocytes (B cells) in the LYMPH NODES -> B symptoms (fever, night sweats, lymphadenopathy)
Leukaemia = cancer of blastic cells in the bone marrow -> overcrowding out of mature cell lines = anaemia, thrombocytopenia
Acute myeloid leukaemia typical presentation?
AML = the most common leukaemia in ADULTHOOD -> ~ 40-60 years old
ACUTE onset of symptoms
Auer rods on film (clusters of myelopyroxidase)
ALL typical presentation?
Either in the children or very elderly
Rapid onset of lymphoblastic symptoms
CML typical presentation?
CML = associated w/ philadelphia chromosome, 9;22,
presents insidiously with a MASSIVELY raised WCC
CLL typical presentation?
The elderly, insidious onset, typically advances v slowly
typical presentation of polycythaemia rubra vera?
> 60
Headaches / dizziness / itch after hot bath
Tx -> venesection or hydroyxurea
Where is vit B12 and foliate absorbed?
Folate = duodenum and prox jejunum (Folate First)
Vit B12 = terminal ileum
Typical presentation of sarcoidosis?
Bilateral hilar lymphadenopathy
bruising
Serum ACE may be ^
typical presentation of antiphospholipid syndrome?
low plts and ^ APTT
PRO coagulable
= recurrent miscarriages + DVTs etc
May be primary or secondary to lupus etc
rare side effect of chloramphenicol?
APLASTIC ANAEMIA -> pancytopenia
How do you diagnose amyloidosis?
BIOPSY (usually of the rectum or subcut tissue) w/ microscopy (get positive congo red stain + red-green biorefringence)
Duration of anticoagulation for DVT?
Provoked -> 3 months then review
Unprovoked -> 6 months then review
In pregnancy -> for remainder of pregnancy and 6 weeks postpartum
Mx of a haemodynamically UNSTABLE patient with PE?
unfractionated heparin continuous infusion and consider for thrombolysis
Treating DVT if confirmed antiphospholipid syndrome?
5 days LMWH with Wafarin and then Warfarin life-long (unless planning for pregnancy)
Side effect of CICLOSPORIN?
gingival hypertrophy (overgrowth of the gums!) ciclosporin is used in RA, dermatitis and psoriasis
Diagnosis + staging of lymphoma?
Dx = Gallium scan + bone marrow biopsy Staging = Arbor staging
Mx of essential thrombocythaemia?
Give Tx if platelets are >1,000
Aspirin 75mg
OR
Hydroxycarbamide if > 60 years or prev thrombosis
Types of blood transfusion reaction?
A Fat Nurse Haemolysed my Labs
A - allergic /anaphylactic -> within ~ 3 hours -> Type I hypersensitivity reaction -> urticaria, pruritus etc -> at increased risk if they have an IgA deficiency
FN - Febrile Non-haemolytic -> fever + headache + flushing
(due to antibody attack of the donor’s WCCs)
Haemolytic transfusion reaction - antibody attack of the donor’s RCCs - in the FIRST HOUR - intra and extra vascular haemolysis - flank pain + haematuria + jaundice
Transfusion related Acute Lung Injury -> pulmonary oedema + resp collapse + RH failure
1st line treatment for CML ?
Bone marrow transplant if young + fit enough
If not = Imatinib (tyrosine kinase inhibitor)
which sub-type of acute myeloid leukaemia responds well to trans-retinoic acid?
promyelocyticluekaemia
t(15;17) on genetics
how should stunted growth in thalassaemia be managed?
Thalassaemia can lead to stunted growth / delayed puberty in children due to pituitary dysfunction
Mx = somatotrophin (synthetic growth hormone)
Under what conditions do you get an eosinophilia?
Parasitic infections
Drugs (gold, penicillin)
Allergic syndromes
Under what conditions do you get a lymphopenia?
AIDS steroid / chemotherapy / radiotherapy malignancy sarcoidosis liver + renal failure
What is the most common inherited bleeding disorder ?
Von Willebrand disease
normally autosomal dominant
most common form is type I
= deficiency in VWF and factor 8
APTT ^
Normal plt count and normal PT
Dx = decreased agglutination of plts on the restocetin cofactor assay
Tx -> Desmopressin (^VWF + factor 8 levels) during a bleeding episode
Should avoid Aspirin
