Interpreting the FBC

Learning Objectives
Interpreting the FBC
Dr Sam Ackroyd
Bradford Royal Infirmary
•
What is a FBC
•
When to do a FBC
•
Interpreting the FBC
•
What further investigations to do
•
When to refer
•
When NOT to refer
•
Tips and common problems
What is a full blood count?
THE RED CELL
4
Measuring the red blood cell
Haemoglobin Hb g/L
 Hb
 RBC
Lysis of red cells
 PCV
Convert cyanmethaemoglobin
 MCV
 MCH
Measure light absorption
 MCHC
 RDW
1
Packed cell volume (PCV) or
Haematocrit (Hct)
Red Blood Count (RBC) and
MCV
 Impedence
measure
counter”
 Voltage proportional to MCV
 Male
>0.52
 Female >0.48
 “Coulter
MCV
 This
Reticulocytes
is directly measured
 Fluorochromes
RNA
 “Polychromasia”
Microcytic anaemia (MCV < 78)
Macrocytic anaemia (MCV>100)
Normocytic anaemia (MCV 79-99)
CASE 1
 70
year old man originally from Pakistan sees
his GP with tiredness.
CASES
11
 He
has a previous Hx of CCF and AF
 As
part of Ix a FBC is performed
12
2
FBC
Blood Film
 Hb
103
9.9
 Platelets 322
 Neutrophils 6.3
 WCC
Ferritin 78 (normal)
 MCV
62 (78-99)
13 (11 - 15)
 MCH 19
(27-31)
 MCHC 22 (32-36)
 RBC 6.5
(4.7 - 6.1)
 reticulocytes 60 (20-80)
 RDW
13
 Re
Haemoglobin Electrophoresis
 High
Performance Liquid Chromatography
(HPLC)
Treatment
 Look
out for it in all Asian patients
 Once
diagnosed patient should be contacted
by thalassaemia genetic counselling service
15
CASE 2
 28
year old previously fit and well recently
moved to the UK from Saudi Arabia
 Presents to his GP with tiredness, abdominal
discomfort and weight loss
 On examination thin and pale
 No other significant findings
16
FBC
 Hb
71
 WCC
13.2
750
 Neutrophils 7.8 Eosinophils 2.6
 Platelets
 MCV
Ferritin = 6 (low)
63 (78-99)
 RDW 16 (11 - 15)
 MCH 25 (27-31)
 MCHC 28 (32-36)
 RBC 3.1
(4.7 - 6.1)
 reticulocytes 25 (20-80)
18
 Re
3
Blood Film
Diagnosis
 Iron
deficiency anaemia
Cause of iron deficiency -
Iron deficiency anaemia
 Stool

sample

1.
2.
3.
 Endoscopy
4.
5.



Commonest cause of anaemia in UK and world wide
Always need to define a cause
Diet
Physiological
Blood loss – GI Ix
Malabsorption – check coeliac screen
Intravascular haemolysis – rare, have elevated LDH
menorrhagia
diet related
In Bradford check stools for Ova
Treatment iron deficency?
Who to refer?
 Ferrous
 Refer
sulphate 200mg tds in adults
Hb 1g/dl per week
 Give for a minimum of 3 months (min 6 weeks
after normal FBC)
 GI side effects try:
Lower dose
Laxatives
Liquid preparation Sytron
 Increase
to gastroenterology if baseline
investigations normal and history indicates
possible GI blood loss / malabsorption
 Refer
to haematology if intolerant of oral iron
and require intravenous iron
4
FBC
CASE 3
 Hb
77
 WCC
12.7
345
 Neutrophils 5.2
 Mother
brings her 6 year old son to see you
 He has had a recent cold but now pale and
tired all the time with little appetite
 Platelets
 MCV
 He
was born with neonatal jaundice but
otherwise has been well
108 (78-99)
18 (11 - 15)
 MCH 28
(27-31)
 MCHC 42 (32-36)
 RBC 3.5
(4.7 - 6.1)
 reticulocytes 180 (20-80)
 RDW
25
26
 Re
Blood Film
Further tests
DCT negative
EMA positive
 FHx positive
 Bilirubin 38


27
Diagnosis

28
Treatment
Hereditary
Spherocytosis
 Depends
on severity
Acid
 Blood transfusions
 Splenectomy
 Cholecystectomy
 Folic
 watch
29
out for Parvovirus B19 (slapped
cheeks)
 remember to screen relatives (FBC, Film,
retics, Bilirubin)
30
5
CASE 4
What tests would you do?
 60
 FBC
year old lady presents with extreme
tiredness
 Two weeks earlier had the Flu jab and then
had back pains and passed very dark urine for
3-4 days
 OE pale with mild jaundice and spleen just
palpable 1cm
 Blood
 UE
film
/ LFT
Should be referred as
emergency to haematology
FBC
 Hb
 Haematinics
64
 WCC
 Bilirubin
 Platelets
11.1
333
 Neutrophils 6.2
 ALT
112 (78-99)
 RDW 20 (11 - 15)
 MCH 28 (27-31)
 MCHC 32 (32-36)
 RBC 3.1
(4.7 - 6.1)
 reticulocytes 270 (20-80)
78 (unconjugated 60)
25
 Alk phos 144
 B12/folate/ferritin - normal
 MCV
33
 Re
Referred to haematology
 Retics
12% 270
++++ IgG
 Haptoglobins <0.06
 LDH 1099
 Urinary haemosiderin – detected
 DCT
6
Diagnosis and Treatment
Haemolysis screen
 AIHA
 History
2er vaccination
 FBC,
 Treatment
pred 1mg/kg
 DCT
Hb increase over time
17.5
 LFT,
in 4 weeks and
now stopped pred and
well
Hb g/dl
14.
 Resolved
and examination
Film, retics
10.5
Series1
7.
3.5
0.
1
5
6
9
days
15
22
28
Haptoglobins, LDH
dip stick
 Urinary haemosiderin
 Specific tests
 Urine
FBC
CASE 5
 Hb
 76
 WCC
year old man presents to her GP with
tiredness and SOBOE
 Previous very well
 Examination pale but well
5.3
9.1
 Platelets 79
 Neutrophils 1.1
 MCV
116 (78-99)
20 (11 - 15)
 MCH 35 (27-31)
 MCHC 33 (32-36)
 RBC 2.4 (4.7 - 6.1)
 reticulocytes 12 (20-80)
 RDW
40
 Re
Blood Film and haematinics
Diagnosis
Ferritin 90
Folate 2.8
B12 <50
 B12
deficient anaemia
low folate)
 (also
7
Investigations
B12 – assay can have rare false negative (consider
checking homocysteine level)
 Serum
 IF
antibody – very specific, but 60 - 85% sensitive
 Parietal
cell antibody – sensitive 90% but 10% false
positive
 Endoscopy
 Schillings
– gastric atrophy (not an essential test)
test – PA v malabsorption – no longer available
Treatment.

Hydroxycobalamin 1mg IM 3 x week for 2 weeks, monthly 3
months then 3 monthly
Or if IF and GPCAb negative

Hydroxycobalamin 1mg PO daily – would need to check levels
improve
consider Folic acid 5mg AFTER B12 commenced for 4 weeks
Check UE day1 and day 5 after starting (risk severe
hypokalaemia)
 Borderline results in asymptomatic – treat as above (no evidence
of benefit though)


B12 deficient anaemia
B12 needed for DNA synthesis
Causes of deficiency:
1. Diet - vegans, breast milk
2. MalabsorptionPernicious anaemia
Ileal resection or gastric bypass surgery
Crohns / Coeliacs
Intestinal stagnant loop
Tropical sprue
Fish tapeworm


When to refer?
 Not
always straight forward - could always
discuss with haematology first
Refer If:
 Not coping with anaemia e.g.angina, heart
failure, falling etc..
 Severe pancytopenia Platelets <50 or
Neutrophils <0.5
 Diagnosis uncertain eg Borderline B12 level
46
FBC
CASE 6
 Hb
 49
 WCC
year old presents with easy bruising
well
 Previously
 OE
101
3.1
 Platelets 15
 Neutrophils 1.0
Bruising and some petechiae
108 (78-99)
17 (11 - 15)
 MCH 31 (27-31)
 MCHC 32 (32-36)
 RBC 3.2 (4.7 - 6.1)
 reticulocytes 10 (20-80)
LUC flag 1.2
 MCV
 RDW
B12 normal
Folate Normal
Ferritin Normal
48
 Re
8
/ folate / ferritin – normal
1% 10
 LFT normal
 B12
Need to refer?
 we
 Retics
should be ringing you!!!!!!!
49
Bone marrow aspirate
Cytogenetics
 G-banded
Diagnosis
 MDS
– RAEB
Prognosis

1.
 Treatment
Azacitidine and BMT
complex karyotype: 44,XY,del(5)(q15), -7, -13, -18, +mar.
2.
3.
4.
5.
Depends on:
Cytogenetics
Number of cytopenia’s
Blast cell count
Transfusion requirement
Age
R-IPSS score median survival between
4 months – 120 months
9
FBC
CASE 7
 Hb
89
 WCC
13.3
504
 Neutrophils 7.1
 77
year old lady is feeling increasingly tired
and more SOBOE.
 Platelets
 She
has a background of CCF, hypertension,
chronic leg ulcers, DVT and Diabetes
 MCV
93 (78-99)
14 (11 - 15)
 MCH 28 (27-31)
 MCHC 33 (32-36)
 RBC 3.2 (4.7 - 6.1)
 reticulocytes 35 (20-80)
 RDW
55
56
 Re
Blood Film
further investigations
 Ferritin
130
Fe - reduced
 TIBC - reduced
 transferrin saturations - 10% reduced
 B12 normal
 Folate nomal
 electrophoresis - normal
 eGFR 45
 Serum
57
Hepcidin “the insulin of iron
metabolism”
Diagnosis
 Anaemia
58
of Chronic Disease
59
60
10
Anaemia of chronic disease
Treatment of ACD
 Hepcidin
acute phase protein - increases
 Free circulating iron reduces
 Body iron stores not deplete just not
accessible
 Is
the anaemia symptomatic?
underlying conditions
 treat
 Consider
IV iron:
Ferritin <150
Iron Saturations <20%
61
Causes microcytic anaemia
MCV <78
1.
2.
3.
4.
Iron deficiency
Haemoglobinopathy
Anaemia of chronic disease
Other – congenital sideroblastic anaemia,
MDS, heavy metal poisoning,
hyperthyroidism
Causes of macrocytic anaemia
MCV >100
1.
2.
3.
4.
5.
6.
7.
8.
Megaloblastic anaemia
Liver disease
Haemolysis
Hypothyroidism
Myelodysplasia
Myeloma
Drugs (antifolate)
Alcohol
62
Causes of normocytic anaemia
MCV 79 -99
Anaemia of chronic disease
Blood loss – acute
Acute illness
Renal failure
MDS
1.
2.
3.
4.
5.
Anaemia summary
 Why
 Any
did you test the FBC?
other clues? -
MCH
MCHC
reticulocytes
blood film
 Are



there concerning findings –
Normal haematinics
More than 1 cytopenia
other symptoms / signs e.g. lymphadenopathy, B symptoms
11
67
12