Audience

  • Highland HSCP

A normal neutrophil count is 2 to 7 × 109/L and neutropenia is defined if the neutrophil count is less than 1.5 × 109/L. Mild neutropenia is 1 to 1.5 × 109/L, moderate neutropenia is 0.5 to 0.99 × 109/L and severe neutropenia is less than 0.49 × 109/L. Patients are at risk of more serious infection when the neutrophil count falls below 1× 109/L and especially when less than 0.5 × 109/L.

Causes

  • Medications. Check BNF
  • Viral infections
  • Autoimmune disease
  • Vitamin B12 or folate deficiency
  • Sepsis
  • Ethnic variations, particularly in Black These are not at increased risk of infection and show a normal neutrophil response to inflammation and infection.
  • Hypersplenism
  • Felty’s syndrome
  • Thyroid dysfunction
  • Nutritional deficiencies eg. anorexia nervosa
  • Bone marrow failure disorders eg. myelodysplasia, aplastic anaemia
  • Bone marrow infiltration eg. acute leukaemia, T-cell large granular lymphocytic leukaemia
  • Congenital syndromes eg. cyclical neutropenia

History and examination

Ask about the above causes, recurrent infections, mouth ulcers and family history. Examine for signs of autoimmune disease, liver disease and lymphadenopathy and splenomegaly. Review older blood tests.

Suggested investigations

  • Liver function tests
  • HIV, hepatitis B and C
  • Blood film
  • TSH
  • Vitamin B12 and folate
  • Ferritin
  • Autoimmune screen if history or examination suggestive

Management

The management will vary from patient to patient depending on differential diagnosis, prior blood counts and clinical concern. Causative medications may not need to be stopped if they are important and the neutrophil count is above 1 × 109/L and there are no recurrent infections. In neutropenia associated with viral infections this may persist for weeks and less commonly for some months.

In general

  • Neutrophil count 1.5 × 109/L and above – rule out secondary causes as per suggested history, examination and Repeat in four weeks’ time and if stable and no concerns then no further investigation.
  • Neutrophil count 1-1.49 × 109/L – rule out secondary causes as per suggested history, examination and investigations. Repeat in two to four weeks’ time and if still low seek advice via Clinical Dialogue service for specific management plan. If there are no associated full blood count abnormalities, film abnormalities or clinical concern patients can usually be monitored in primary care
  • Neutrophil count below 1 × 109/L. A blood film will have been performed in these situations and the results can guide frequency and timing of further tests. In general, someone with a neutrophil count persistently below 1 × 109/L after a repeat in two weeks needs haematological assessment.
  • If the neutropenia is associated with other blood count or film abnormalities or abnormalities on examination or recurrent infections then make a formal referral
  • If the patient is of Black African or Middle-Eastern ethnicity then a neutrophil count is commonly 0.8 to 2 × 109/L with no clinical consequence. This is a diagnosis of exclusion after ruling out other causes and seeing a persistent low count without increased risk of infection. Please perform the above investigations and if normal and the neutrophil count remains above 1 × 109/L then no further investigation is required.
  • If a patient with a neutrophil count less than 1 × 109/L presents with fever or with clinical signs of sepsis they should be admitted and treated with intravenous antibiotics as per the policy for neutropenic sepsis.

Editorial Information

Last reviewed: 29/01/2024

Next review date: 31/01/2027

Author(s): Haematology Department .

Version: 1

Approved By: APPROVED TAM Subgroup of the ADTC

Reviewer name(s): Dr P Forsyth, Consultant Haematologist.

Document Id: TAM611