Raised White Cells

Severity

Range

Mild
WCC 11–15
Moderate
WCC 15–25
Severe
WCC > 25 or blasts on film

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Neutrophilia — infection Causes

Bacterial infection (commonest)Localised abscess / collectionEndocarditis, osteomyelitisSevere viral / fungal (less typical)

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Neutrophilia — non-infective Causes

Tissue injury — trauma, surgery, burns, MI, PEAcute pancreatitisInflammatory flare (RA, IBD, vasculitis)Stress response, seizures, exercise

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Drugs Causes

Corticosteroids (demargination)G-CSF, lithiumAdrenaline / β-agonistsSmoking (chronic mild)

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Lymphocytosis Causes

Viral — EBV, CMV, HIV seroconversion, hepatitisCLL (older patients, indolent)Pertussis (children)Post-splenectomy

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Eosinophilia Causes

Drug reactions (DRESS, allergy)Atopy — asthma, eczema, allergic rhinitisParasitic infections (travel)Vasculitis (EGPA), hypereosinophilic syndromesAdrenal insufficiency

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Haematological malignancy Causes

Acute leukaemia (blasts on film)CML (very high WCC, basophilia)CLL, lymphomaMyeloproliferative — PV, ET, myelofibrosis