Considerations Prior to Seeing the Patient

What we know so far:

  1. 38 year-old woman with extreme leukopenia
  2. Outpatient setting

Definitions:

  1. Leukopenia = white cell count < 4.5 x 109/L

What is most likely from an etiologic standpoint (one answer)?

a
Severe congenital neutropenia
b
Chemotherapy-induced neutropenia
c
Leukopenia caused by eosinopenia
d
Benign ethnic neutropenia

We will review the results in the section on Labs, but you learn before seeing the patient that the hemoglobin and the platelet count are normal and the white cell differential reveals a low neutrophil count and normal lymphocyte, monocyte, eosinophil and basophil counts.

What we know so far:

  1. 38 year-old woman with extreme leukopenia, manifested by neutropenia
  2. Outpatient setting

Definitions:

  1. Leukopenia = white cell count < 4.5 x 109/L
  2. Neutropenia = absolute neutrophil count < 1.5 x 109/L

Classification of neutropenia

Classification of neutropenia:

Classification schemes for neutropenia:

Differential diagnosis of isolated neutropenia:

Acquired

Transient

  • Infection related
    • viral
      • EBV
      • CMV
      • HIV
      • Influenza
    • bacterial
    • Protozoal
  • Drug-induced
    • chemotherapeutic agents
    • anticonvulsants
    • antimicrobials
    • antipsychotics
    • antirheumatics
    • antithyroid agents

Chronic

  • Immune-mediated
    • primary autoimmune neutropenia
    • secondary autoimmune neutropenia associated with other autoimmune diseases
      • SLE
      • RA
      • Felty syndrome
      • Large granular lymphocyte leukemia
  • Chronic idiopathic/benign neutropenia

Congenital

  • Not associated with infections
    • constitutional/ethnic neutropenia
    • benign familial neutropenic
  • Associated with infections
    • severe congenital neutropenia (SCN)
    • cyclic neutropenia
    • neutropenia associated with complex phenotypes typically diagnosed in childhood

What clinical parameters would lead to an accelerated work up of the patient with neutropenia?

a
Other cytopenias
b
History of recurrent, severe infections
c
Elevated mean cell volume
d
African ethnicity
e
Fever
febrile neutropenia is an emergent condition and patient should be admitted to hospital for IV antibiotics and further evaluation