Haematology Flashcards
Presence of tartrate-resistant acid phosphatase
Hairy cell leukaemia
how long does transfusion related lung injury occur following blood transfusion
within 6hrs
Dyspnoea, distended neck veins and pink frothy sputum following blood transfusion
Fluid overload
(transfusion associated circulatory overload-TACO)
Impaired degredation of factors 5a and 8a
protein S deficiency
factor V unable to be broken down by protein C due to a substitution mutaiton
factor V leiden
causes of howel jolly bodies
splenectomy
autosplenectomy from sickle cell disease
translocation between chrom 11 and 14 resulting in BCL-1 overexpression
mantle cell lymphoma
translocation between chromosome 14 and 18 leading to BCL2 overexpression
follicular lymphoma
what lymphoma is associated with centrocytes and centroblasts
follicular lymphoma
what knind of ig are RhD Abs
IgG
(can cross the placenta)
what is the complication of RhD negative pregnant mother previously exposed to RhD blood
haemolytic disease of the newborn
hydrops fatalis
what screening technique is used to determine blood group
indirect antiglobulin technique
what are the pillars of pt blood management
optimise haemopoesis (iron, B12, folate, EPO)
minimise blood loss/ bleeding (eg. tranexamic acid, blood sparing techniques, stop anticoag meds)
optimise physiological tolerance to anaemia
what is the shelf life of red cells
35 days at 4C
(must be transfused within 4hrs of leaving fridge)
what is the shelf life of platelets
stored at 20C for 7 days
transfusion rates of blood products
RBC –> 1 unit over 2-3 hours
Plts, FFP, cryo –> 1 unit over 20-30 mins
indications for blood transfusion
major blood loss if 30% loss
critical care Hb <70g/L
post chemo Hb <80g/L
symptomatic anaemia
when is platelet transfusion contraindicated
heparin induced thrombocytopenia thrombosis
TTP
indications for platelet transfusion
indications for FFP transfusion
massive transfusion
liver disease
replacement of single coag factor
DIC only if active bleeding
TTP
what is cryoprecipitate
FFP that has been centrifuged and precipitate collected
contains higher concentration of fibrinogen, fVIII and VWF, IgA, albumin
requirements of blood for severely immunocompromised
irradiated blood
requirements of blood for intra-uterine /neonatal transfusions and for elective transfusion in pregnant women
CMV negative
requirements of blood for severely allergic people
washed
examples of acute transfusion reactions
ABO incompatibility
anaphylaxis
infection (bacterial)
febrile non-haemolytic
Transfusion related circulatory overload
examples of chronic transfusion reactions
delayed hamolytic transfusion reaction
GVHD
infection (viral/HBV, malaria, CJD)
post transfutsion purpura
Iron overload
signs of acute transfusion reaction
early:
raide in temp
raise in HR
fall in BP
symptoms (dependent on cause):
rigors ,fever, flushing, vomiting, dyspnoea, loin pain, chest pain, urticaria
differentials if reaction is happening within minutes of transfusion
anaphylaxis
ABO incopatibility
febrile non-haemolytic transfusion reaction
describe febrile non-haemolytic transfusion reaction
During / soon after transfusion (blood or platelets),
rise in temperature of 10C, chills, rigors
Common before blood was leucodepleted, now rarer
Have to stop or slow transfusion; may need to treat with
paracetamol
Cause: White cells can release cytokines during storage
mild-moderate
describe allergic transfusion reaction
Common especially with plasma
Mild urticarial or itchy rash sometimes with a wheeze
During or after transfusion
Usually have to stop or slow transfusion
IV antihistamines to treat (and prevent in future if recurrent)
Cause:
Allergy to a plasma protein in donor so may not recur again, depending on how common the allergen is
Commoner in recipients with other allergies and atopy
mild-moderate
describe ABO incompatibility (s&S and Mx)
Symptoms and signs of acute intravascular haemolysis- IgM
Restless, chest/ loin pain, fever, vomiting, flushing, collapse, haemoglobinuria (later);
↓BP & ↑HR (shock), ↑Temp
Stop transfusion – check patient / component
Take samples for FBC, biochemistry, coagulation,
Repeat x-match and Direct Antiglobulin Test (DAT)
Discuss with haematology doctor ASAP
severe-fatal
describe bacterial contamination reaction
(transfusion)
Restless, fever, vomiting, flushing, collapse.
↓BP & ↑HR (shock), ↑Temp
Bacterial growth can cause endotoxin production which causes immediate collapse
From the donor (low grade GI, dental, skin infection)
Introduced during processing (environmental or skin)
Platelets >red cells > frozen components (storage temp)
severe-fatal
describe anaphylactic transfusion reaction
↓BP & ↑HR (shock),
very breathless with wheeze,
often laryngeal &/or facial oedema
Mechanism:
IgE antibodies in patient cause mast cell release of granules & vasoactive substances
Most allergic reactions are not severe, but few are e.g. in IgA deficiency
severe-fatal
respiratory complications of transfusion
Transfusion Associated Circulatory Overload (TACO)- most common out of other resp complications
Transfusion Related Acute Lung Injury (TRALI)
Transfusion Associated Dyspnoea (TAD)
presents within 6hrs of transfusion
describe Transfusion Associated Circulatory Overload (TACO)
Pulmonary oedema / fluid overload;
SOB, low sats, raised HR, raised BP
fluid overload on CXR and cardiac failure
examples of transfusion transmitted infections
maleria
Hep B/C
zika
HIV1+2
HTLV1+2
parvovirus
CJD
describe delayed haemolytic transfusion reaction
within 1 week
IgG mediated extravascular haemolysis
Jaundice, dark urine, renal failure
DAT positive
describe GvsHD
always fatal
in severely immuno compromised recipiants who cant kill donor lymphocytes so donor lymphocytes attack host
avoid by giving irradiated blood products
features: severe diarrhoea, liver failure, skin desquamation,
bone marrow failure
describe the mechanism of haemolytic diseas eof the newborn
RhD -ve mother is pregnant for the first time with a RhD+ve fetus
blood enters circulation during pregnancy or labour, mother creates antibodies
anti Rh abs are IgG so can cross the placenta
If the fetus in the next pregnancy is Rh+ve then the Abs will attack fetus RBCs
leads to fetal anaemia and haemolytic disease of the newborn and hydrops fetalis
prevension of haemolytic disease of the newborn
always give anti-D prophylaxis in Rh-ve mothers in first pregnancy within 72hrs of sensitising event (eg. bleed)
anti D coats Rh Ag on fetus RBC and they get removed by the spleen before sensitisation
examples of RhD sensitising events
spontaneous miscarriages if surgical evacuation needed and therapeutic terminations
amniocentesis and chorionic villous sampling
abdominal trauma (falls and car accidents)
external cephalic version (turning the fetus)
stillbirth or intrauterine death
complications of anti-kell Abs on fetus
Kell causes reticulocytopenia in fetus as well as haemolysis
usually less severe as anti-D
what is basophilic stippling a sign of
lead poisoning
alcohol excess
sideroblastic anaemia
hypochromic microcitic RBC with anisopoikilocytosis
iron deficienct anaemia
hypersegented neutrophil (>5 segments) sign of
B12/ folic acid deficiency
anti DNA synthesis meds eg. methotrexate
what are target cells a sign of
iron deficiency
hyposplenism
thalassaemia
liver disease
what are howell jolly bodies? and what are they a sign of
remnant of nucleus- usually removed by spleen when it filters the RBCs
sign of hyposplenism
features of megaloblastic anaemia
hypersegmented neutrophil
large MCV
features of hyposplenism
howell jolly bodies
target cells
causes of iron deficiency anaemia
chronic blood loss
malabsorption
poor diet
causes of B12 def
malabsorption
pernicious anaemia
poor diet
causes of hyposplenism
IBD
Coeliac
sickle cell
SLE
splenectomy
trauma
what deficiencies seen in coeliac
Iron, B12, folate, fat, calcium
what deficiencies are seen in IBD
B12, bile salts (Fe deficincy due to chronic diseas/ bleeding)
What description is given to red blood cells which are typically polychromatic and stain heavily for the presence of RNA?
reticulocyte
small molecule drug used in the treatment of CLL and MOA
ibrutinib
Tyrosine kinase inhibitor
revesible agent of rivaroxiban
andexenet alfa
mutation in hereditary spherocytosis
Spectrin
ANK1/ ankyrin
mode of inheritance of G6PD def and hereditary spherocytosis
G6PD- X linked RECESSIVE
hereditary sphero- aut dominant
second most common genetic cause of pancreatic insufficiency leading to malabsorption and steatorrhoea (2nd to CF)
Shwachman diamond syndrome
Heparin induced thrombocytopenia is associated with the formation of antibodies directed against what autoantigen?
platelet factor 4
causes of acanthocytes (spike cells )
Liver disease, hyposplenism
causes of basophilic stippling
Lead poisoning
megaloblastic anaemia
myelodysplasia
thalassaemia
causes of burr cells (echinocyte)
artefact if sat in EDTA prior film
uraemia
renal failure
GI bleeding
stomach carcinoma
causes of heinz bodies
G6PD deficiency
chronic liver disease
causes of howell jolly bodies
post splenectomy, hyposplenism (sickle cell disease, coeliac, IBD, amyloidosis)
megaloblastic anaemia
hereditary spherocytosis
What is a pelger huet cell
hyposegmented neutrophil with 2 lobes like a dumbell
congenital
myeloid leukaemias, myelodysplastic syndromes
what is a right shift and what causes it
increased production of hypersegmented neutrophils (hypermature)
megaloblastic anaemia
Anaemia cut off Hb values for men women and pregnant women
men <135g/L
women <115g/L
cut off for ferrous sulphate treatment
1st trim women <110g/L
2/3rd trim <105g/L
posr partum <100g/L
causes of microcytic anaemia
iron deficiency
anaemia of chronic disease
sideroblastic anaemia
thalassaemia
causes of normocytic anaemia
acute blood loss
anaemia of chronic disease
BM failure
renal failure
hypothyroidism
hameolysis
pregnancy
casues of macrocytosis
non-megaloblastic
pregnancy
hypothyroidism
reticulocytosis
alcohol excess
cirrhosis
megaloblastic
B12/ folate deficiency
antifolates (eg. phenytoin)
cytotoxic drugs
clinical signs of iron deficiency anameia
angular stomatitis
koilonychia
brittle hair
plummer vinson syndrome (web-like growth of membranes in the throat that makes swallowing difficult)
describe anaemia of chronic disease
inhibition of RBC production driven by chronic cytokine release
IFN, TNF and IL1 reduce EPO receptor production
IL6 stimulates upregulation of hepcidin which decreases iron absorption from the gut (as it inhibits transferrin)
ferritin (intracellular protein store) high as Fe sequestered in macrophages to deprive pathogen from getting Fe
what is sideroblastic anaemia and what are the signs
ineffective erythropoisis leading to iron loading casueing haemosiderosis
can be congential (eg. X linked ALAS2 mutation)
aquired (myelodysplastic syndromes, lead poisoning, alcohol XS, anti TB drugs)
signs:
ringed sideroblasts in BM (erythroid precursurs with iron deposition in mitochondria in a ring around the nucleus)
describe hereditary spherocytosis
AD
spectrin or ankyrin deficiency
defect in RBC membrane
effect suseptibility with parvovirus B19 infection
extravascular haemolysis - splenomagaly
describe G6PD deficiency
glucose-6-phosphate dehydrogenase
most common inherited RBC enzyme defect
X linked recessive
attacks- rapid anaemia with jaundice
triggers- fava beans/ broad beans (1 days after eating), drugs (primaquine, aspirin, sulphonamides- ~2/3 days after starting), acute stressors eg infection
difference between warm and cold haemolytic anaemias
warm- occurs at body temperature, IgG, spherocytes
casues: primary idiopathic, lymphoma, CLL, SLE, methyldopa
cold occurs <37C, IgM, associated with raynauds
casues: primary idiopathic, EBV, mycoplasma
describe TTP
Abs against ADAMTS13 or inherited deficiency
enzyme responsible for vWF breakdown so leads to build up of vwF in long strands which then act as a ‘cheese wire’ cutting up RBCs (MAHA) and increased activation of plts
pentad of:
MAHA
fever
renal impairment
neuro signs
thrombocytopenia
What protein is typically defective in hereditary elliptocytosis?
spectrin
The classical triad is of nail dystrophy (nail loss, longitudinal ridging), oral leukoplakia (white patches in the mouth) and skin pigmentation (lace like hyperpigmentation of skin creases) is suggestive of
dyskeratosis congenita
What scoring system can be used to calculate the probability of developing heparin induced thrombocytopenia?
4T score
what might be given for somoone with high risk of neutropenia during chemo
filgrastim- a granulocyte- colony stimulating factor
what are the features of post thrombotic syndrome and what is the management
painful, heavy calves
pruritus
swelling
varicose veins
venous ulceration
Mx: graduated compression stockings
what is the revaersal agent of dabigatran
idarucizumab
Most common inherited thrombophilia (procoagulative state)
heterozygous factor V leiden
mutation in factor V making it resistant to breakdown by protein C
where is vitamin B12 absorbed and what condition causes reduced B12 absorption
terminal ileum
chrons
test used to diagnose paroxysmal nocturnal haemoglobinuria
Ham’s test
causes of massive splenomegaly
CML
PRV
Kala-azar
test used to investigate hereditary spherocytosis.
osmotic fragility test
stain used which is useful in the differentiation of AML and ALL
sudan black B
what is Tartrate-resistant acid phosphatase stain used for
diagnosing hairy cell leukaemia
