Neutropenic fever

Fever in patient on chemotherapy:

1. infection
2. tumor necrosis
3. drug reaction 
4. transfusion reaction 

Causes:

1.  secondary to cytotoxic chemotherapy 
2. radiotherapy, 
3. some targeted therapy agents
4. pancytopenia due to malignant infiltration of the bone marrow. 

Occult source of infection: LUCCAASS

1. Lung
2. Urinary bladder
3. Cardiac, CNS
4. Abdomen, Arthritis
5. Skin, Spine

After cytotoxic chemotherapy neutropenic fever is most commonly defined as 

• single oral temperature of ≥ 38.3°C (celcius) or 
• temperature of ≥ 38°C sustained for over 1 hour in a patient with a neutrophil count of <0.5 × 109/L (or <1.0 × 109/L if the nadir is anticipated to drop to < 0.5 × 109/L in the next 48 hours).

 The risk of sepsis is greater with 

1. profound neutropenia (neutrophil count <0.1 × 109/L), 
2. prolonged neutropenia (<0.5 neutrophils for ≥7 days) or 
3. rapid rate of decline in neutrophils 
4. presence of other risk factors, such as 

• intravenous cannula or 
• urinary catheters. 

Clinical features 

• high fever,
• non-specifically unwell. 
• If patients have been taking paracetamol or steroids then fever or symptoms may be masked. 
• Examination is usually unhelpful in defining a primary source of the infection. 
• Hypotension 

Investigations:

• CBC with ESR
• Blood cultures (both peripheral and from central lines), 
• Urine culture, 
• Chest X-ray 
• Swabs for culture & sensitivity test (throat, central line, wound). 
• RBS, Blood urea, S creatinine, electrolytes

Management:

• High-dose intravenous antibiotics – within 1 hour of admission
  • empirical broad-spectrum antibiotics according to local antibiogram
  • Monotherapy/combination therapy 
  • Example:
    • piperacillin–tazobactam or  meropenem with or without 
      • gentamicin if high risk on MASCC score, 
      • metronidazole if anaerobic infection is suspected, 
      • vancomycin where Gram-positive infection is suspected

• Antibiotics should be adjusted according to culture results. 
• If there is no clinical improvement after 36–48 hours→  review antibiotics and add antifungal cover (e.g. fluconazole or liposomal amphotericin B). 
• Granulocyte–colony-stimulating factor (G–CSF) can be used to hasten neutrophil recovery 
• Other supportive therapy
  • oxygen
  • intravenous fluids, 
  • inotropic therapy, 
  • ventilation 
  • hemofiltration,