AKT · Haematology/Marrow failure & white cells

Neutropenia & neutropenic sepsis

Low neutrophil count (commonly post-chemotherapy) → sepsis with a blunted inflammatory response

Overview

A reduced neutrophil count (commonly from chemotherapy, also marrow failure, drugs, autoimmune, severe infection). NEUTROPENIC SEPSIS — a temperature >38°C (or other signs of sepsis) in a patient with neutrophils ≤0.5 ×10⁹/L (or <1.0 and falling) — is an oncological EMERGENCY: the inflammatory response is blunted, so deterioration is rapid, and empirical IV antibiotics must be given within 1 hour without waiting for cultures or imaging.

Recognise

Fever (or hypothermia/sepsis signs) in a patient at risk — typically 7–14 days after chemotherapy; signs may be subtle (blunted inflammatory response)
Neutrophils ≤0.5 ×10⁹/L (or <1.0 and falling); may have no localising signs despite serious infection
Sources: lines/catheters, gut translocation, chest, skin; Gram-positive (lines) and Gram-negative organisms

Red flags

Neutropenic sepsis = EMERGENCY → empirical IV piperacillin-tazobactam within 1 hour (Sepsis Six); do NOT wait for the neutrophil count if clinically septic
Septic shock → resuscitation/critical care; consider lines as the source

Differentials & how to tell them apart

Non-neutropenic sepsissepsis with a normal neutrophil count — same urgency, broader differential

Drug/chemo-induced neutropenia without infectionlow count but no fever/sepsis — monitor, growth factors

Marrow failure/leukaemianeutropenia as part of pancytopenia/infiltration

Investigations

FBC (neutrophils), blood cultures (peripheral + each lumen of any central line) BEFORE antibiotics but without delaying them; lactate, U&Es, LFTs, CRP; cultures of likely sources (urine, sputum, line, wound); CXR; do NOT delay antibiotics for investigations.

Management

Empirical IV piperacillin-tazobactam within 1 hour (don't wait for cultures/count) + Sepsis Six

1Any fever/sepsis in a recently-chemotherapy patient is neutropenic sepsis until proven otherwise → take cultures but give empirical IV piperacillin-tazobactam WITHIN 1 HOUR and start the Sepsis Six. Do not wait for the neutrophil count.Gate: Speed is everything — antibiotics within the hour; consider the central line as the source (culture each lumen, consider removal); add MRSA/Gram-positive cover per local policy.
2Resuscitate, risk-stratify (MASCC), source control, and step down/switch to oral when stable with recovering counts; G-CSF and prophylaxis for high-risk regimens.

Empirical IV piperacillin-tazobactam WITHIN 1 HOUR (NICE) — do not wait for cultures/counts; add cover (e.g. vancomycin) for line/MRSA risk per local policy; Sepsis Six

Resuscitation (Sepsis Six) + source control — fluids, oxygen, monitor; consider removing an infected line

G-CSF in selected cases; risk-stratify (MASCC) — specialist; step down/oral switch when stable and recovering counts

Prophylaxis in high-risk chemo — G-CSF/antimicrobial prophylaxis to prevent it

Key points

Fever (>38°C) + neutrophils ≤0.5 (or <1.0 falling), typically 7–14 days post-chemo = NEUTROPENIC SEPSIS → empirical IV piperacillin-tazobactam WITHIN 1 HOUR + Sepsis Six, BEFORE the count comes back. Blunted inflammatory response → deterioration is rapid and signs subtle. Suspect the line.

Monitor & prognosis

Sepsis response/lactate, cultures, neutrophil recovery; line as source.

Good with prompt antibiotics; delay markedly increases mortality.

Source: NICE CG151 (neutropenic sepsis); cross-ref acute_care (Sepsis Six)