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ABNORMAL FBC IN ADULTS

    • Important instructions and notes - please click to read.

      Instructions: Click the links (blue text), icons () and drop-downs (▶) for further information. Select the appropriate clinical scenario to adjust the pathway.

      This is an adapted version of the source material referenced/linked below. Please see the original source for full details.

      Please read our medical disclaimer - this pathway may not be suitable for your particular patient or healthcare setting/system.
      If you would like to commission a more appropriate localised pathway please get in touch.

      This pathway is adapted from Camden CCG: Abnormal FBC Results Guidance

    • Anaemia section

    • Polycythaemia

    • Important instructions and notes - please click to read.

      Instructions: Click the links (blue text), icons () and drop-downs (▶) for further information. Select the appropriate clinical scenario to adjust the pathway.

      This is an adapted version of the source material referenced/linked below. Please see the original source for full details.

      Please read our medical disclaimer - this pathway may not be suitable for your particular patient or healthcare setting/system.
      If you would like to commission a more appropriate localised pathway please get in touch.

      This pathway is adapted from Leicester Polycythaemia referral guidelines

    • High Haemoglobin / Haematocrit <div class="navybox"> <p><b><u>Local cut off values vary - please check with your local Haematologists</u></b></p> <ul> <li><a href="https://cks.nice.org.uk/topics/polycythaemia-erythrocytosis/diagnosis/diagnosis/" target="_blank">CKS suggest the cut-offs below</a> (accessed April 2021) <ul> <li>WOMEN: Hb &gt; 165 g/L | Hct &gt; 0.48 </li> <li>MEN: Hb &gt; 185 g/L | Hct &gt; 0.52</li> </ul> </li> <li><a href="https://bestpractice.bmj.com/topics/en-gb/178/investigations" target="_blank">BMJ Best Practice suggest the cut-offs below</a> (accessed April 2021) <ul> <li>WOMEN: Hb &gt; 160 g/L | Hct &gt; 0.48 </li> <li>MEN: Hb &gt; 165 g/L | Hct &gt; 0.52</li> </ul> </li> </ul> </div>
      WOMEN: Hct > 0.48
      MEN: Hct > 0.52

      ↓

    • ↓

      REFER URGENTLY TO HAEMATOLOGY

    • ↓

      If no reason for urgent referral (and cause unclear)
      Repeat FBC at 4-6 weeks (uncuffed sample)

      ↓

      Hb and or Hct remains high

      • Assess for splenomegaly / 'B' symptoms → CKS: History and Examination details
      • Exclude secondary causes:
        • check oxygensaturation
        • suggest modify smoking and alcohol intake
        • review diuretics (avoid thiazides)

      ↓

      Cause unclear and Hb remains high associated with

      • high white cell count or plateletcount
      • splenomegaly ± ‘B’ symptoms
      • history of venous or arterial thrombosis
      • symptomatic despite clear secondary cause

      ↓

      REFER TO HAEMATOLOGY

    • Features that warrant urgent haematology referral

      • Hb ≥ 200g/l (male) or 180g/l (female)
      • Hct > 0.6 (male) 0.56 (female)
      • Hb +/- Hct high and recent:
        • Thrombosis*
          • including DVT/PE, CVA/TIA, MI/Unstable angina, PVD
        • Abnormal bleeding*
        • Visual symptoms*
        • Neurological symptoms*

      * Discuss urgently with on-call haematologist

      Common causes

      • Secondary polycythaemia
        • Smoking
        • COPD/asthma
        • Fibrotic lung disease
        • Sleep apnoea
        • Steroid or testosterone use-either as therapy or by bodybuilders
        • Cyanotic heart disease
      • Relative (measured decrease in plasma volume)/Apparent polycythaemia
        • Not a genuine polycythaemia, but a raised Hb due to relatively increased red cell mass i.e by decreased plasma volume 
        • Hypertension, alcohol excess, diuretics, dehydration
      • Polycythaemia vera- one of the myeloproliferative neoplasms
      • Erythropoietin excess (rare)
        • Renal cell or hepatocellular carcinoma
        • Cerebellar haemangioma
        • Wilms Tumour
      • Endocrine (rare)
        • Cushing's syndrome
        • Conn's syndrome
      • Inherited disorders of erythropoietin receptors

      SOURCE: BUKU Haematology

    • Platelets

    • Important instructions and notes - please click to read.

      Instructions: Click the links (blue text), icons () and drop-downs (▶) for further information. Select the appropriate clinical scenario to adjust the pathway.

      This is an adapted version of the source material referenced/linked below. Please see the original source for full details.

      Please read our medical disclaimer - this pathway may not be suitable for your particular patient or healthcare setting/system.
      If you would like to commission a more appropriate localised pathway please get in touch.

      This pathway is adapted from Camden CCG: Abnormal FBC Results Guidance | CKS: Platelets - abnormal counts and cancer

    • Normal 150 - 400 x 109/l

    • ↓

      REFER URGENTLY TO HAEMATOLOGY
      If < 20 x 109/l or any bleeding Refer for same day assessment

    • ↓

      REFER URGENTLY TO HAEMATOLOGY if:

      • Evidence of pancytopenia (Hb < 100 g/L, neutrophils < 1 × 109/L)
      • Splenomegaly or lymphadenopathy
      • Pregnancy
      • Upcoming surgical or interventional procedures

      Otherwise REFER to haematology if persists over 4-6 weeks and is unexplained

    • ↓

      Repeat monthly and refer if:

      • progressive decrease
      • other FBC abnormalities
      • unwell

    • ↓

      REFER URGENTLY TO HAEMATOLOGY

    • ↓

      Treat secondary causes
      Check Hb/Ferritin (follow Polycythaemia pathway if appropriate)

      ↓

      Refer to haematology if:

      • persistent unexplained platelets > 600 x 109/l on at least 2 occasions 4-6 weeks apart
      • or platelets 450 - 600 x 109/l in association with other FBC abnormalities

    • ↓

      No further action required

      • CKS: Comprehensive assessment of thrombocytopenia
      • Check history: including travel, drugs, alcohol
      • Ask about bleeding history:
        • Spontaneous skin/mucosal bleeding, bruising, GI bleeding, epistaxis, gums, menorrhagia
        • Post dental / surgical haemorrhage
        • Haemarthoses / muscle haematomas

      Thrombocytopenia causes

      • Infections
        • Viral infection including EBV (usually resolves within few weeks)
        • Also: HIV, Malaria, TB
      • Drugs
        • NSAIDs, Heparin, Digoxin, Quinine, anti-epileptics, antipsychotics, PPIs
        • Alcohol
      • Malignancy
      • Liver & Renal disease
      • Aplastic anaemias
      • B12/Folate deficiency
      • Autoimmune / ITP / SLE
      • CKS: Comprehensive assessment of thrombocytosis

      Features that warrant URGENT haematology referral

      • Abnormal bleeding
      • Neurological symptoms
      • Platelets > 1000 x 109/l
      • Platelets > 600 x 109/l with
        • recent thrombosis
          • including DVT/PE, CVA/TIA, MI/Unstable angina, PVD
        • high risk for thromboembolism or CVD
      • splenomegaly
      • Other significantly abnormal FBC indices

      Other symptoms suggestive of malignancy → 2 WEEK WAIT CANCER REFERRAL

      Thrombocytosis causes

      • Primary thrombocytosis - Myeloproliferative (likely if splenomegaly and plt > 1000)
      • Secondary thrombocytosis - More common
        • Reactive
          • Infection, inflammation haemorrhage, exercise, tissue damage, post-surgery, haemolysis
        • Malignancy
        • Hyposplenism/Splenectomy
        • Iron deficiency

    • Neutrophils

    • Normal 2.0 - 7.5 x 109/l (40 - 75%)
    • Isolated neutropenia is very common

    • ↓

      • Unwell, Febrile or on Chemotherapy
      • Lymphadenopathy
      • Splenomegaly
      • other cytopenia

      ↓

      EMERGENCY REFERRAL

      ↘

      Well and afebrile
      Do blood film

      ↓

      If normal: Repeat FBC and blood film in 1 week

      ↓

      Refer urgently if persistent

    • ↓

      Check blood film +/- B12, Folate, Ferritin, ANA

      ↓

      Repeat FBC in 4 - 6 weeks

      ↓

      Refer

      • if perists and unexplained
      • or if other FBC abnormalities
      • or if history of recurrent infections/ulcers

    • Neutrophilia > 7.5 x 109

      ↙


      Infection most common cause

      Repeat FBC 4-6wks with inflammatory markers

      ↓

      Refer if

      • cause unclear
      • unable to manage in primary care
      • neutrophilia persists

      ↓

      • Refer if > 15 x 109/l
      • OR associated splenomegaly
      • OR other FBC abnormalities

    • Causes of Neutropenia

      • Infection
        • EBV, Hep B,C, HIV
      • Ethnic variation common
        • Afro-Caribbean, SE Asian
      • Drugs
        • eg. Phenytoin, Carbimazole, Antipsychotics, Clotrimoxazole
      • Endocrine (eg. thyroid)
      • Malignancy
        • marrow infiltration, chemo/radiotherapy, myeloma – consider very urgent serum electrophoresis and urine BJP if suggestive symptoms
      • Connective tissue (eg. RA, Gout)
      • Autoimmune
      • B12, Folate, Iron deficiency
      • Excess alcohol
      • Liver disease (Cirrhosis)

    • Causes of Neutrophilia

      • Infection
        • Bacterial, some viral eg VZV,HSV, some fungal & parasitic
      • Drugs (eg. Steroids)
      • Malignancy
        • eg.Carcinoma,LymphomaLeukaemia
      • Connective tissue (eg. RA, Gout)
      • Haemorrhage, Haemolyis, Hypoxia, tissue damage, infarction

    • Lymphocytes

    • Normal 1.3 - 3.5 x 109/l (20 - 45%)

    • ↓

      Refer for treatment of underlying cause
      Or if remains low on repeat testing

    • ↓

      If features of viral illness & otherwise well, Repeat once resolved 4-6 weeks
      Otherwise check Infectious Mononucleosis screen and repeat 4 – 6 weeks

      ↓

      Refer to haematology if persistenting

    • Neutrophilia > 7.5 x 109

      ↙


      Infection most common cause

      Repeat FBC 4-6wks with inflammatory markers

      ↓

      Refer if

      • cause unclear
      • unable to manage in primary care
      • neutrophilia persists

      ↓

      • Refer if > 15 x 109/l
      • OR associated splenomegaly
      • OR other FBC abnormalities

    • ↓

      REFER URGENTLY TO HAEMATOLOGY

    • Causes of Lymphopenia

      • Drugs (eg. Steroids)
      • Infection – postviral common (exclude HIV, Legionella)
      • Malignancy
        • marrow infiltration, chemo/radiotherapy, myeloma – consider very urgent serum electrophoresis and urine BJP if suggestive symptoms
      • Renal or hepatic impairment
      • Connective tissue (eg. RA, SLE, Sarcoid)
      • Anorexia Nervosa
      • Primary immune defieciency

    • Features that warrant URGENT referral

      • If > 20 x 109/l or
      • Lymphadenopathy
      • Splenomegaly
      • Anaemia
      • Other cytopenia
      • Weight loss, night sweats, PUO

      Causes of Lymphocytosis

      • Infection eg EBV, CMV, Pertussis, Mumps, Rubella
      • Stress
      • Vigorous exercise
      • Post splenectomy
      • Haematological Malignancies eg ALL, CLL, NHL

    • Eosinophilia

    • Eosinophilia
      > 0.44 x 109/l

      ↓

      Check history: Drugs, Travel, Atopy
      ↓
      Repeat FBC + Blood Film within 1-2 weeks

      Consider:

      • ESR,CRP, IgE, ANA
      • Chest X-Ray
      • Stool for OCP
      • Serology for Strongyloides + relevant to travel history (eg Schistosomiasis)
      ↳ Discussion with microbiology / ID as appropriate

      ↓

      Eosinophilia > 1.5 x 109/l peristing for > 3 months
      or rising without any cause

      ↓

      Refer to haematology

    • Eosinophilia causes to consider:

      • Asthma / allergic disorders
      • Infections (esp. Parasitic eg. Schisto, also malaria, TB, fungal, recovery from any infection)
      • Drugs (eg. Penicillin, Allopurinol, Amitriptylline, Carbamazepine)
      • Smoking
      • Connective tissue disorders (eg. RA, PAN, Churg-Strauss)
      • Endocrine (eg. Addison’s)
      • Skin disease (Eczema, psoriasis, dermatitis herpetiformis, erythema multiforme)
      • Malignancy (eg. Lymphoma, Leukaemia, CA lung/stomach)
      • Löffler’s syndrome, Endocarditis, Post-splenectomy, Irradiation