Definitions
| Term | Definition |
|---|---|
| ANC | (WBC ×10⁹/L) × (% segmented neutrophils + % bands) / 100 |
| Neutropenia | ANC <1500/µL (mild 1000–1499, moderate 500–999, severe <500/µL) |
| Profound neutropenia | ANC <100/µL |
| Fever (most guidelines) | Single temp ≥38.3°C, or ≥38.0°C sustained over ≥1 h |
| Febrile neutropenia (FN) | Fever plus ANC <500/µL, or <1000/µL and expected to fall below 500 |
Compute it: ANC Calculator.
When it is an emergency
Febrile neutropenia is an oncologic emergency. Treat as sepsis until proven otherwise.
- A neutropenic child can be bacteraemic with minimal signs — fever may be the only sign; the inflammatory response is blunted.
- Profound or prolonged neutropenia, an indwelling central line, AML/relapse/HSCT, or haemodynamic instability mark the highest risk.
- The danger is gram-negative sepsis (including Pseudomonas); deterioration can be rapid. Do not wait for localising signs or for culture results.
The one-hour rule
| Step | Target |
|---|---|
| Recognise fever in a neutropenic/at-risk child | Triage immediately, do not wait in queue |
| Assessment + cultures (peripheral + each lumen) + FBC | Without delaying antibiotics |
| First-dose empiric IV antibiotic | Within 1 hour of presentation (door-to-needle) |
| Reassess / escalate | Within the first hours; senior + oncology review |
Take cultures but never let sampling delay the antibiotic past one hour.
Empiric antibiotic choice
- Monotherapy with an anti-pseudomonal beta-lactam: piperacillin-tazobactam, cefepime, or a carbapenem (meropenem) — per local protocol and resistance patterns.
- Add an aminoglycoside and/or glycopeptide for shock/instability, suspected line infection, known resistant colonisation, or severe mucositis.
- Adjust for documented penicillin allergy and local antibiograms; do not delay the first dose to find the “perfect” agent.
After the first dose
- Source control: examine line, perianal area, mouth, skin; image as indicated.
- Continue antibiotics until afebrile and ANC recovering (rising >500/µL), or per local stop rules.
- Validated low-risk scores (e.g. for selected stable patients) may permit step-down/oral pathways — only in clearly low-risk children, per protocol and oncology input.
Decision support for qualified clinicians only — verify against current primary guidelines and your clinical judgement.