FBC Flashcards
What is in a standard FBC?
Haemoglobin (Hb)
White Blood Count (WBC)
Platelet Count (Plt)
Red Cell Count (RBC)
Haematocrit (HCT)
Mean Cell Volume - Red cell (MCV)
Mean Cell Haemoglobin (MCH)
what can you add onto FBC?
Reticulocyte count
Red cell ditribution
Differential White Cell Count (where applicable)
Neutrophils
Lymphocytes
Monocytes
Eosinophils
Basophils
And if appropriate
Blood Film
What does Haemaglobin (Hb) tell you? ranges?
Adult Male 130 - 180 g/l
Adult Female 115 - 165 g/l
Amount of haemoglobin in whole blood
low - Anaemia
high - Polycythaemia
What does WCC tell you? ranges?
Adult 3.6 - 11.0 x109/l
number of WBC - Neutrophils and lymphocytes make up the majority of the white cells in the blood, so these two cell types are usually the cause of a raised total white cell count.
High WCC (leukocytosis) can be due to 1. reactive (infection, inflammation, post-surgery)
2. Steroids (stress response i.e endogenous steroids or medication i.e exogenous steroids) and
3. Haematological (acute leukemias)
4. Drugs (lithium)
Low WCC (leukopenia) can be due to
1. infection, autoimmune (consumption)
2. Medications eg immunosuppressants etc
3. B12/folate deficiency, iron deficiency,
4. bone marrow failure
what does platelet count tell you? range?
Adult 140 - 400 x109/l
High (thrombocytosis) -
1. reactive (inflammation/infection)
2. myeloproliferative
iron deficiency, hyposplenism, underlying malignancy
Low (thrombocytopenia)
Mild: over 100 × 109/L.
Moderate: 50–100 × 109/L.
Severe: less than 50 × 109/L.
-
ACUTE
consumption (infection, bleeding), acute virus, medications, DIC, TTP, HUS, ITP, heparin induced thrombocytopenia, pre-eclampsia/HELLP.
CHRONIC
hypersplenism, cirrhosis, alcohol excess, ITP, autoimmune, medications,
Platelet counts below 50 x 109/L will result in easy or spontaneous bruising and prolonged bleeding times. They may present with nosebleeds, bleeding gums, heavy periods, easy bruising or blood in the urine or stools.
Platelet counts below 10 x 109/L are high risk for spontaneous bleeding. Spontaneous intracranial haemorrhage or GI bleeds are particularly concerning.
what does haematocrit tell you? range?
Adult Male 0.40 - 0.54 l/l
Adult Female 0.37 - 0.47 l/l
Percentage of the blood made up from RBC
a decrease in haematocrit, alongside a Hb drop, indicates dilutional effect
High haematocrit usually seen alongside high Hb in polycythemia
→ hyperviscosity → predispose to thrombi → venesection to reduce haematocrit
what does red cell count tell you?
Red Cell Count (RBC) - number of RBC present per unit volume of blood
Used alongside Hb and HCT for same reasons
What does mean cell volume tell you? range?
Adult 80 - 100 fl
average size of RBC
Shows type of anaemia : microcytic, normocytic, macrocytic
what is red cell distribution? when is it useful?
Useful where there is a false normocytic MCV due to mix of micro and macro eg in iron, B12 and folate deficiency in coeliac disease
what does reticulocyte count tell you? range?
0.2-2%
number of reticulocytes (immature RBCs)
high retic and anaemia/no anaemia = bone marrow working to correct anaemia therefore suggests haemolysis/bleeding
low retic and anaemia = bone marrow is the problem / deficiency means you cant make stuff
high retic and no anaemia = as above or compensating for high O2 demands
what does neutrophils tell you? ranges?
Adult
1.8 - 7.5
x109/l
High neutrophils (neutrophilia) suggests acute bacterial infection
Neutropenia (drugs: immunosuppressants, chemo/radiation, biologics infliximab and rituximab, carbimazole, clozapine)
what does lymphocytes tell you? normal range?
1.0 - 4.0
x109/l
High lymphocytes (lymphocytosis) suggests viral infection or haematological malignancy
Low lymphocytes (lymphopenia) suggests infection or immunosuppression
what does eosinophils tell you? range?
0.1 - 0.4
x109/l
High (eosinophilia) suggests allergies/atopy, parasitic infection, autoimmunity, abx, GI disease, asthma, malignancy
National association for the advancement of cells coloured pink
Neoplasia (CML/hodgkins), Allergy, Atopy/Asthma, Churg-Strauss/ Connective tissue disorders, Parasite infections
what does blasts in the FBC tell you?
Blasts are immature cells that are usually only found in the bone marrow where they complete their maturation before being released into the circulation. The presence of high numbers of blasts in the circulating blood is abnormal and could be caused by leukaemia, hence this should prompt an urgent haematology assessment including a blood film and a bone marrow biopsy.
Causes of an elevated blast count include:
Acute leukaemia
Myeloproliferative disorders
Reactive (severe infection or treatment with G-CSF)
Cytotoxic agents (chemotherapy)
what do steroids do to WCC
Glucocorticoids (e.g., dexamethasone, methylprednisolone, prednisone) are known to increase the white blood cell (WBC) count upon their initiation. The increase in WBC count is predominantly neutrophils
