Definition
Isolated neutrophil count below 1.5 x 109/l. (A neutrophil count of between 1-5-2.0 x 109/l whilst below the normal range is unlikely to be of any clinical significance).
Patients with mild neutropenia (>1) are not generally at any increased risk of infection.
Drugs most often associated with neutropenia include antipsychotics, sulphonylureas, propylthiouracil, carbimazole, sulphonamides, co-trimoxazole, bendroflumethiazide, anticonvulsants, NSAIDs and ranitidine.
C.M & L.W 31-07-23
Who to refer:
- Neutrophil count <0.5 and evidence of sepsis – contact the on-call haematology registrar for urgent advice
- Neutrophil count <1 on repeat testing
- Neutrophil count <2 on repeat testing and the presence of any of the clinical findings as described above.
Who not to refer:
- People of Afro-Caribbean or Middle Eastern ethnicity have a lower normal range for the neutrophil count (constitutional or ethnic neutropenia). This is of no clinical consequence. Such patients should only be investigated if their neutrophils are <1.0 on repeat testing. No further monitoring required.
- Neutrophil counts consistently >1.5. These patients can be given the diagnosis of chronic idiopathic neutropenia. No further monitoring is required.
- Neutrophil count >1 but <1.5 repeat at 6 months. If clinical features of concern develop or neutrophil counts falls <1 refer to haematology. Otherwise patients can be given a diagnosis of chronic idiopathic neutropenia and no further routine monitoring is required.
How to refer:
SCI gateway to the Department of Haematology WGH or SJH.
For all:
- Assess patient for symptoms e.g. recurrent infections, mouth ulcers etc.
- Establish if patient is of an ethnic background known to be associated with lower neutrophil counts (See ‘Who not to refer’).
- Review medication (see above)
- Examine for lymphadenopathy and splenomegaly
- Repeat FBC:
- If neutrophil >1 then repeat at 6 weeks
- If neutrophil count <1 repeat at 1 week.
For persistent neutropenia do the following tests:
- Blood film
- B12 and folate, Ferritin. Treat if deficiency is detected
- HIV, HBV, HCV serology
- If additional clinical features to suggest a diagnosis of SLE, RA or other connective tissue disorder check CCP, ANF, dsDNA (if ANF positive).
Neutropenia in primary care. Hay et al. BMJ. 2014 Sep 11;349.