Neutropenic Sepsis

Question 1

Define

Answer 1

DEFINITION: the development of sepsis in a patient with neutropenia.

Diagnostic criteria:

• Temperature > 38 degrees
• Neutrophil count < 0.5 x 109 /L

CAUTION: patients can have neutropenic sepsis without a fever because they may be on anti-pyretic medications or steroids

Question 2

Causes/ Risk factors

Answer 2

Incidental Neutropenia

• Congenital - ethnic variation, cyclical neutropenia in children (all VERY RARE)
• Acquired
  
  • Decreased/ineffective neutrophil production: bone marrow infiltration, aplastic anaemia, B12/folate deficiency, chemotherapy, radiotherapy
  • Accelerated turnover: Felty’s syndrome, hypersplenism, malaria
  • Others: toxoplasmosis, dengue fever

Febrile Neutropenia

• DEFINITION: temperature > 38.5 or two consecutive readings of > 38 for two hours and an absolute neutrophil count < 0.5 x 109 /L

Question 3

Epidemiology

Answer 3

Most common in patients with cytotoxic chemotherapy

Question 4

Symptoms

Answer 4

Check history for:

• High-risk features: active cancer, recent chemotherapy, use of immunosuppressants or immunosuppressive illness (e.g. HIV)
• Chronic kidney disease
• Recent blood products
• Intravascular devices (e.g. central line)

Examination findings:

• Signs of infection may be minimal
• Pyrexia
• Features of infective endocarditis
• Lymphadenopathy
• Skin rashes

Question 5

Investigations

Answer 5

FBC (check neutrophil level)

Blood cultures (check for sepsis)

Others - blood film, D-dimer (for DIC), U&Es, creatinine, LFTs