Audience

• Highland HSCP 

This is usually a reactive phenomenon and only rarely will represent a primary haematological disorder. It is unusual for a reactive neutrophilia to be above 100 × 10⁹/L. The finding of basophilia points towards a myeloproliferative neoplasm; especially chronic myeloid leukaemia. If there is an associated monocytosis which is persistent see section on monocytosis.

Causes

• Infection – especially bacterial
• Smoking
• Medications g. corticosteroids, GCSF, lithium
• Malignancy (haematological or solid tumour)
• Stress events g. trauma, seizures, myocardial infarction, eclampsia etc.
• Autoimmune diseases or other inflammatory processes
• Hyposplenism
• Myeloproliferative neoplasms such as chronic myeloid leukaemia, myelofibrosis and chronic neutrophilic leukaemia (these conditions are often identified or suspected on the blood film)

History and examination

Careful clinical evaluation asking about infective symptoms, travel history, smoking history and into the above causes. Examine for features of autoimmune disease, lymphadenopathy and splenomegaly. Review older blood tests.

Suggested investigations

• CRP or ESR
• Blood film
• Dependant on history and examination

Management

The management will vary from patient to patient depending on differential diagnosis, prior blood counts, result on repeat and clinical concern.

• If persistent basophilia suggest referral or discussion via Clinical Dialogue
• If neutrophil count persistently above 20 × 10⁹/L without a reactive cause suggest referral
• If there is neutrophilia and splenomegaly or blood film abnormalities then suggest referral
• If unexplained inflammatory process suggest refer to general medicine depending on localising features