Neutropenic fever

Background

• ANC = (total WBC) x (%segs + %bands)
• Nadir usually occurs 5-10d after chemo
• Duration of neutropenia depends on type of cancer treatment
  • Solid tumor Rx: <5d
  • Hematologic malignancies: 14d or longer
• (Leukemia or lymphoma) + chemo most commonly associated with neutropenia

Definition

1. ANC <500 OR <1000 w/ predicted nadir of <500 in 48h AND
2. Fever ≥ 38.3˚C (100.9˚F) once OR sustained temp ≥38 (100.4) for >1hr
   1. Oral temp (do not obtain rectal temp)

Common Causes

• Definitive cause only found in 30%

1. Endogenous flora 80%
   1. E Coli, Enterobacter, anaerobes
2. Skin
   1. Staph, strep
3. Respiratory tract
   1. Step pneumo, klebsiella, corynebacterium, pseudomonas
4. Other
   1. C. diff, mycobacterium, candida, aspergillus

Diagnosis

1. Classic manifestations of infection are frequently NOT seen
2. Check skin, oral cavity, perianal area, entry sites of indwelling cath sites

DDx

1. Transfusion reaction
2. Medication allergies and toxicities
3. Tumor-related fever

Work-Up

1. AVOID rectal temp
2. CBC
3. Chemistry
4. LFTs
5. UA/UCx
   1. May not show WBCs or leuk esterase given neutropenia
6. Sputum studies
   1. Gram stain
   2. Cx
7. BCx x 2
   1. 20-30cc blood (adult); 3-9cc (child)
   2. May take both samples from CVC (if present)
8. Cx any indwelling catheters
9. LP
   1. If neuro abnl or suspicious
10. Site-specific specimens
    1. Nasopharyngeal wash (in pts with URI)
       1. RSV, influenza
11. Stool (if indicated)
    1. C dif
    2. O&P
    3. Cx
12. CXR
13. CT (if necessary)
    1. Sinuses
    2. Chest
    3. A/P

High-Risk/Special Infections

1. Neutropenic enterocolitis (typhlitis)
2. Zygomycosis (see Mucormycosis)
3. Hepatosplenocandidiasis
   1. After neutropenic fever resolves and ANC has come up allowing abcess formation
   2. Treat w/ amphotericin B

Treatment

1. If suspect infection then treat (even if afebrile)
   1. 3rd or 4th gen cephalosporin (cefepime 2g or ceftazidime 2g) OR
   2. Carbapenem (imipenem 500mg or meropenem 1g) OR
   3. Zosyn 4.5g +/- aminoglycoside (gent 2-5mg/kg, amikacin) OR
   4. Antipseudomonal fluoroquinolone (moxi, levo, cipro) +/- vanco
2. Add Amphotericin B 0.5-1 mg/kg qd if fever >72 h or candida in esophagus, urine or stool
3. Add anaerobic coverage (clindamycin, metronidazole) if peritonitis or abd pain

Disposition

• Low risk patients
  • D/c using Multinational Association for Supportive Care in Cancer (MASCC) risk index

Patient Clinical Factor Score

Patient Clinical Factor	Score
Severity of illness: no symptoms or mild symptoms moderate symptoms	5 3
No hypotension	5
No chronic obstructive pulmonary disease	4
Solid tumor or no fungal infxn	4
No dehydration	3
Outpt at onset of fever	3
Age < 60yo	2

≥21 pt = low risk for SBI

Source

LLSA 2009; Halfdanarson Onc Emergencies Mayo Clin Proc June 2006

• Tintinalli