L36: Molecular medicine - Febrile neutropenia

Question 1

Presentation of febrile neutropenia

Answer 1

After starting chemotherapy:

• Uncontrollable shivering (episodes)
• Fever
• Nothing to suggest site of infection
• V. low WBC count
• V. low platelet count

Question 2

Investigating febrile neutropenia

Answer 2

Blood cultures: central line, peripheral line
Mouth and skin swabs
Chest x-ray

Question 3

Febrile neutropenia

Answer 3

• Common in severely neutropenic patients
• High rate of bacteraemia (30% of patients with febrile neutropenia)
• Infections from endogenous gut and skin flora
• V. high mortality in patients with gram-negative bacteraemia (without empiric Rx)
• Improved outcome with empiric antibiotic treatment started at presentation
• Infections arise from damaged barriers in gut and skin
• Cannot transfuse with neutrophils due to short lifecycle

Question 4

Aetiology of febrile neutropenia

Answer 4

• Staphylococci: mainly coag neg staph and also S. aureus
• Streptococcus
• Aerobic gram neg bacilli: mainly E. coli and also Klebsiella sp. and pseudomona aeruginosa

Question 5

Risk of infection

Answer 5

• Risk of infection rises below 0.5x10^9/L and <0.1 daily risk is 1%
• Risk of severe infection if neutrophils less than 0.1: for 1wk = 33%, for 6wks = 100%

Question 6

Initial management

Answer 6

Tazocin (piperacillin and tazobactam) = active against almost all bacteria

PLUS gentamicin = active against almost all aerobic gram neg bacilli

Question 7

Treatment

Answer 7

• Empiric antibiotic therapy is standard
• Use of antibiotic prophylaxis to prevent infection
• Much greater care about IV lines to prevent infection
• Determinants of treatment: how severe is the neutropenia, is there evidence of neutrophil count increasing, has person had resistant bacterial infections previously

Question 8

Nursing patient in isolation?

Answer 8

• No impact on survival of patients
• Most infections from skin and gut flora
• HEPA filtered single rooms for BM transplant patients
• Implications of isolation for prolonged period

Question 9

Use of prophylactic antibiotics

Answer 9

• Usually a quinolone (ciprofloxacin)
• Can reduce number of episodes and increase survival rate
• Important to be aware of increasing antibiotic resistance
• Uncommon in NZ

Question 10

Haematopoietic growth factors

Answer 10

• Reduces duration and depth of neutropenia

- G-CSF prophylactically if risk of febrile neutropenia >20%

Question 11

Reducing intensity of chemotherapy

Answer 11

• Reduces depth of neutropenia

- Potential impact of outcome for patient