USMLE Prep - Medical Reference Library

Febrile Neutropenia — Risk Scores, Broad‑Spectrum IV Antibiotics, and Antifungal Escalation

System: Hematology Oncology • Reviewed: Sep 2, 2025 • Step 1Step 2Step 3

Synopsis:

Defined as fever with ANC <500 (or expected). Start broad‑spectrum IV antibiotics within 60 minutes of presentation. Use MASCC/CISNE scores to triage for inpatient vs outpatient therapy; add antifungal coverage if persistent fever after 4–7 days or earlier if instability or imaging suggests fungal disease.

Key Points

  • Use the highest‑yield diagnostic test early; do not let testing delay time‑critical therapy.
  • Set objective targets and reassess frequently.
  • Plan definitive source control or disease‑specific therapy when indicated; document follow‑up and patient education.

Algorithm

  1. Draw cultures and labs; start antipseudomonal IV antibiotics within 60 minutes.
  2. Risk‑stratify for admission vs outpatient; daily reassessment.
  3. Escalate to antifungals if persistent fever or instability; adjust per cultures and imaging.

Clinical Synopsis & Reasoning

Defined as fever with ANC <500 (or expected). Start broad‑spectrum IV antibiotics within 60 minutes of presentation. Use MASCC/CISNE scores to triage for inpatient vs outpatient therapy; add antifungal coverage if persistent fever after 4–7 days or earlier if instability or imaging suggests fungal disease.


Treatment Strategy & Disposition

Stabilize ABCs. Initiate guideline‑concordant first‑line therapy with precise dosing and continuous monitoring. Escalate to advanced/procedural interventions based on explicit failure criteria. Define ICU, step‑down, and ward disposition triggers; involve specialty teams early.


Epidemiology / Risk Factors

  • Risk varies by comorbidity and precipitants; see citations for condition‑specific data.

Investigations

TestRole / RationaleTypical FindingsNotes
CBC with differential and blood cultures (peripheral + line)DiagnosisConfirm neutropenia; identify pathogen
CXR/CT chest and urinalysisSourceCommon foci
MASCC/CISNE risk scoresDispositionGuide site of care

High-Risk & Disposition Triggers

TriggerWhy it mattersAction
ANC <500 with sepsis criteria or hypotensionHigh mortalityBroad IV antibiotics within 60 min; ICU
CVC infection or pneumonia imagingSourceAdjust coverage; IR/surgery if needed
Mucositis with odynophagiaEnteric translocationAdd anaerobic coverage if indicated
Persistent fever >72 hResistant/fungalBroaden incl. antifungals
Poor performance status or comorbiditiesDispositionAdmit even if low-risk scores borderline

Pharmacology

Medication/InterventionMechanismOnsetRole in TherapyLimitations
Piperacillin‑tazobactam, Cefepime, or MeropenemEmpiric antibioticsHoursAntipseudomonal coverageTailor to cultures
Add Vancomycin for catheter infection, MRSA concerns, or instabilityGram‑positive coverageHoursSelected indicationsDe‑escalate if no target
Antifungal therapy (echinocandin/voriconazole) if persistent fever 4–7 daysAntifungal escalationDaysHigh‑risk or persistent feverGuided by imaging/markers

Prognosis / Complications

  • Outcome depends on timeliness of diagnosis and definitive therapy; monitor for complications.

Patient Education / Counseling

  • Provide red‑flag education, adherence guidance, and explicit return precautions; arrange timely specialty follow‑up.

References

  1. IDSA/ASCO febrile neutropenia guidelines — Link