• Often discovered as an incidental finding in a routine full blood count.
  • The normal lower level is influenced by a person's race. The widely accepted lower level of 2 x 109/L is appropriate for Caucasians, but levels of 1.5 x 109/L or even lower may be normal for other ethnic groups.


Signs and Symptoms

  • Infections - particularly viral (including human immunodeficiency virus(HIV)), also malaria, typhoid, TB. Acute changes are often noted within 1 to 2 days of infection and may persist for several weeks
  • Drugs - neutropenia with antipsychotic medication has been a significant problem in recent years
  • Autoimmune disease – isolated autoimmune neutropenia or in association with systemic lupus erythematosus (SLE) or rheumatoid arthritis
  • Nutritional - B12 deficiency, folate deficiency, alcohol dependency, anorexia nervosa
  • Splenomegaly
  • Bone marrow pathology e.g. leukaemia, myelodysplasia, aplastic anaemia, bone marrow infiltration

History and Examination

  • Frequency and severity of infections
  • Mouth ulcers
  • Recent viral illness
  • Exposure to drugs and toxins
  • Symptoms of malabsorption
  • Symptoms suggesting reduced immunity
  • Consider that many drugs can induce neutropenia. Most important are antipsychotics, anticonvulsants, and antithyroid drugs
Drug-induced neutropenia
  • Anti-inflammatory drugs e.g. aminopyrine, phenylbutazone, salazopyrine
  • Anti-bacterial drugs e.g. chloramphenicol, co-trimoxazole, sulfasalazine, penicillins
  • Anticonvulsants e.g. phenytoin, carbamazepine
  • Antithyroids e.g. carbimazole
  • Phenothiazines e.g. chlorpromazine, thioridazine
  • Psychotropics and antidepressants e.g. clozapine, mianserin, imipramine
  • Many others including gold, penicillamine, mepacrine, amodiaquine, ticlopidine, tolbutamide and some herbal remedies
  • Cytotoxic agents, including radiation
  • Mouth ulcers
  • Fever
  • Signs of infection
  • Jaundice
  • Lymphadenopathy
  • Hepatomegaly
  • Splenomegaly
  • Signs of autoimmune or connective tissue disorders

Red Flags

Neutropenia can be associated with life threatening infection. It is most significant when the total neutrophil count is less than 0.5 x 109/L.


FBC – look at haemoglobin, platelets, and blood film.

Determine the type of neutropenia for management:

Classification Neutrophil Count
Mild 1.0 - 2.0 x 109/L
Moderate > 0.5 < 1.0 x 109/L
Severe < 0.5 x 109/L

In persistent, moderate neutropenia without an obvious cause, consider other tests.

Other Tests

  • Anti-nuclear antibodies (ANA)
  • Rheumatoid factor
  • B12 and folate
  • Serum protein electrophoresis (SPE)
  • HIV serology
  • Liver enzymes
  • Hepatitis B serology


Neutrophils less than 1.0 x 109/L

  • Risk of significant bacterial infection increases when neutrophils less than 1.0 x 109/L, but more significant if less than 0.5 x 109/L.
  • If unwell or fever, arrange urgent referral.

If well and afebrile:

  • advise patient to seek medical attention if they become unwell or febrile
  • repeat FBC in 48 hours. If neutropenia remains less than 1.0 x 109/L, discuss with a haematologist

Neutrophils 1.0 to 2.0 x 109/L

  • Repeat FBC in 1 to 2 weeks
  • If neutropenia persists for more than 6 weeks, investigate further
  • Only request non-acute haematology assessment (after the other tests are performed) if the neutrophils are persistently below 1.0 x 109/L, or if other significant blood count abnormalities develop
  • If the neutropenia appears stable after a few months and there are no other abnormalities, check every year for two years. After which, no further follow up is required if blood count remains stable and the patient is well

Drug-induced neutropenia

  • If a drug cause is suspected, and if white blood cell count is less than 3 x 109/L or neutrophils less than 1.5 x 109/L, stop the suspected drug
  • Check full blood count in one week and advise patient to seek medical attention if they become unwell or febrile

Suggested algorithm for management of Neutropenia


Referral Criteria

  • Arrange urgent medical assessment if severe neutropenia and unwell or febrile. However, if the patient is known to the Haematology Department, contact the department directly.
  • Request non-acute haematology assessment if:
    • Neutrophils less than 1.0 x 109/L but well. Recommend repeat FBC after 48 hours to confirm neutropenia and assessment for reversible cause before referring
    • Include copies of all bloods (FBC and Blood Film) as well as any extra tests that have been arranged

Referral Instructions

e-Referral Service Selection

  • Specialty: Haematology
  • Clinic Type: Not otherwise specified
  • Service: DRSS-Eastern-Haematology-Devon CCG- 15N

Referral Forms

DRSS Referral Form

Supporting Information

Pathway Group

This guideline has been signed off by NEW Devon CCG.

Publication date: July 2016


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