Abnormal White Cell Count
White cell count abnormalities -assessment and evaluation
Monocytes- Constitute 3-8 % of the WCC Remain for a relatively short time in the circulation- after which they migrate to tissues and body cavities where they differentiate into macrophages They play a role in the inflammatory process ( members of the mononuclear phagocyte system ) Good evidence exists to suggest that blood monocytes consist of several populations
Monocytosis –Associated with infection and inflammatory process Causes can be ○ Reactive monoytes Infection- commonest cause Inflammatory conditions as collagen vascular disease chronic neutropenia splenectomy hemolytic anaemia ITTP Haematopoetic and non Haemtopoetic neoplasms ○ Neoplastic Monocytes several primary hematologic neoplasms harbor neoplastic monocytes including CMML , AMl with monocytic differentiation and myeloproloferative neoplasms as CML
Neutrophilia-Main WCC that respond to bacterial infections Common finding – rarely due to haematological diorder Commonest cause is bacterial infection ○ clinical context ○ raised inflammatory markers as CRP ○ Severe infection -myeloid left shift with toxic granulation on the blood film ( vacuolation and Dohle bodies )
causes-Infection Inflammation Necrosis Steroids Pregnancy Smoking Underlying cancer e.g CML. Red flags -A rapid rise Unwell patient Splenomegaly Cytopenias Abnormal blood film Left shift ( more immature as they are being released earlier ).Consider spurious neutrophilia ( eg due to platelet clumping or cryoglobulinaemia ) If cause unclear ask for CRP , U/E , LFT , Immunoglobulins , Serum free lite assay , Autoimmune screen , PSA ( based on clinical suspicion ) For well people a repeat in 4-6 wks is widely recommended
Refer- Suspected acute leukaemia Suspected Chronic myeloid leukaemia -usually moderate ↑↑ in neutrophil count > 50 x 109 with a left shift and a prominence of myelocytes ( basophilia and eosinophilia may also be present ) Unexplained leucocytosis > 50 x 109 Neutrophilia > 15 x 109 ( persistent and unexplained ) Associated splenomegaly or other FBC abnormalities
Lymphocytes-Main cells of the immune system and include T , B and natural killer cells Responsible for antibody production , direct cell-mediated killing of virus-infected and tumour cells Constitute about 25 % of the WCCs- most rapidly motile cells
Lymphocytosis – Ref flags-Fever of unknown origin Weight loss Night sweats Lymphadenopathy Hepatosplenomegaly Associated anaemia , thrombocytopenia or neutropenia Suspected acute leukaemia Rapidly rising lymphocyte count or in excess of 20 x 109
Causes- Primary-Lymphoid malignancies ○ CLL ( most common ) ○ Lymphoma ○ Monoclonal B Lymphocytosis. Reactive -Viral ( EBV , CMV, HSV , VZV ) Stress lymphocytosis ○ Drug induced ○ septic shock ○ acute MI ○ trauma. Chronic -Cig smoking Autoimmune disorder Chronic inflammation Sarcoid ↑↑ BMI/ Metabolic syndrome
Referral-No clear cause – consider repeating in 4-6 wks with blood film + glandular fever/HIV screen ( if clinical suspicion ). Refer urgently to r/o Neoplastic lymphocytosis Unexplained persistent lymphocytosis > 10 x 109 – refer routinely. Lymphocyte morphology can help distinguish between reactive and neoplastic causes. If atypical lymphocytes present consider infectious mononucleosis and viral serology
Basophils –Make up < 1 % of leukocytes ( least common ) Contain histamine and share many properties with mast cells Function not fully understood Play a role in immediate hypersenstivity disorders as well as atopy , allergic contact dermatitis and possible autoimmune diseases as SLE Estimated lifespan 60-70 hrs. Basopenia -A low count is difficult to demonstrate Common causes- excess glucocortocoids , acute inflammation , hyperthyroidism. Basophilia -rarely significant clinically myeloproliferative disorders
Eosinophils –Make up 1-6 % of WCC- regarded as inflammatory cells that play an imp role in protection against helminth infection and pathogenesis of inflammation Eosinophila can be caused by a wide variety of conditions which range from allergic , rheumatological , infectious , neoplastic and rare idiopathic disorders Marked eosinohilia ie > 1.5 x 109 should always be investigated further aggressively Eosinophilic infiltration of tissues can cause end organ damage ( can be irreversible and life threatening ) Can be ○ Mild 0.4 -1.5 x 109 ○ Moderate 1.5 to 5 x 109 ○ Severe > 5 x 109 Commonest cause worldwide is parasitic infestation
Assessment –Detailed medical hx Thorough physical examination Check for allergic disorders , skin rashes and cardiorespiratory , GI and constitutional symptoms Detailed travel history ( even in remote past ) Detailed drug history Risk factors for malignancy. Further testing -Blood film Inflammatory markers CRP / ESR Renal , LFT and bone profile LDH Vit B12 CXR Serum IgE Autoantibodies if evidence of autoimmune dis eg ANA , ENA , anti-dsDNA , RhF , ANCA Stool culture for parasites. causes of eosinophilia -Myeloproliferative disorders May also be present with Hodgkin’s lymphoma and T-cell lympoma.Infections -particularly parasites Drugs e.g penicillins , carbamezapine Asthma / atopic dermatitis / acute urticarial Conn tissue disease e.g Rh arthritis, Polyarteritis nodosa, Wegeners granulomatosis ) Solid malignancy ( eg breast , renal and lung cancer ) Hypereosinophilic syndrome- diagnosis of exclusion ( associated with end organ damage , particularly cardiac )
Management –> 1.5 x 109 and severe or potentially severe life threatening clinical manifestations or eosinophil rising rapidly-Discuss with O/C Haematologist ( tel ) to arrange an urgent assessment. Unclear cause-Repeat FBC Also ask for Us&Es , CRP, auto-immune screen Stool for ova and parasites Consider CXR-Persistent unexplained > 1.5 x 109 for 3 months – Refer Rising without an obvious cause – Refer If travel hx- d/w Infectious dis/ Micro
References
- Evaluation of Patients with Leukocytosis Lyrad K Riley MS et al AAFP 2015 https://www.aafp.org/afp/2015/1201/p1004.html
- Complete Blood Count in Primary Care BPAC NZ better medicine https://bpac.org.nz/Supplement/2008/May/complete-blood-count.aspx
- Leuokopenia Elizabeth Birk-Urowitz Family and Community Medicine – University of Toronto via https://dfcmopen.com/wp-content/uploads/2014/11/Leukopenia.pdf
- King’s Health Partners Haematology Institute and Network GP Referral guide Adult Haematology https://www.kingshealthpartners.org/assets/000/002/297/GSTT_-_khp_joint_adult_haematology_original.pdf
- Incidental finding of lymphocytosis in an asymptomatic patient BMJ 2009 ; 338: b2119
- Lymphocytopenia by Mary Territo MD MSD Manuals professional version
- Practical approach to the patient with hypereosinophilia Roufosse, Florence et al. Journal of Allergy and Clinical Immunology, Volume 126, Issue 1, 39 – 44 https://www.jacionline.org/action/showCitFormats?pii=S0091-6749%2810%2900660-3&doi=10.1016%2Fj.jaci.2010.04.011
- Haematology in Primary Care Dr Josh Wright Sheffield Teaching Hospitals
- UH Bristol Haematology referral guideline for Primary Care May 2016
- Monocytes an overview by ScienceDirect
- Ask the hematopathologist : Diagnostic Approach to Monocytosis The Hematologist July-August 2016 , Volume 13 , Issue 4
