Fever in a Child With a Port and a Penicillin Anaphylaxis Label
A 7-year-old with precursor B acute lymphoblastic leukaemia in maintenance therapy (daily 6-mercaptopurine, weekly methotrexate) arrives at 18:00 with a home temperature of 38.6 °C four hours ago, now 38.9 °C. She has a dual-lumen port, mild oral mucositis, one episode of vomiting and no diarrhoea. HR 132, RR 26, BP 96/58, SpO₂ 98%. Her ANC five days ago was 0.4 × 10⁹/L. Last chemotherapy was nine days ago. She is alert but quiet and clinging to her mother. The waiting room holds 11 patients with a three-hour wait, and there is one negative-pressure room available. The allergy band documents anaphylaxis to penicillin at age 3 (hives, wheeze, hypotension).
1. What must happen in the first 60 minutes, and how do you manage the waiting room and the isolation room?
Read the worked answer
Treat this as an emergency, not a routine fever. Fever in a neutropenic child can be the only sign of sepsis, and deterioration can be rapid and subtle.
First 60 minutes
- Move the child out of the general waiting area immediately - a neutropenic child should not sit among children with respiratory and gastrointestinal infections. Use the negative-pressure room, or ask the charge nurse to relocate another patient. Escalate if refused.
- Apply a mask to the child, perform hand hygiene, and confirm the temperature with an oral, axillary or temporal thermometer. Never use a rectal route in a neutropenic child.
- Blood cultures from each port lumen and from a peripheral site before antibiotics, plus urine culture (clean catch or catheter, never a bag specimen), and a respiratory viral panel. Add throat, stool and chest x-ray if symptoms direct you.
- Do not delay antibiotics for cultures. Target the first dose within 60 minutes of triage.
- Labs: CBC with differential, electrolytes, renal and liver function, CRP, lactate if unwell, glucose.
- Examine for a source: oral cavity, port site, skin folds, perianal area (inspect only), lungs, and mental status. Weigh the child for dosing.
- Notify the oncology team and document the fever, cultures and antibiotic times.
Reasoning. The judgement being tested is spatial as much as clinical: protecting a neutropenic child from the waiting room is part of the resuscitation, and the clock starts at triage, not at the doctor's assessment.
2. Which empiric antibiotic would you expect, given the documented penicillin anaphylaxis? When should vancomycin be added?
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Empiric choice
- Standard monotherapy is an antipseudomonal beta-lactam: cefepime, piperacillin-tazobactam or meropenem.
- With documented anaphylaxis (hives, wheeze, hypotension), avoid piperacillin-tazobactam because it shares the penicillin side chain.
- Cefepime has a different side chain and low cross-reactivity, but for a true anaphylaxis many institutions prefer meropenem (cross-reactivity around 1%) or aztreonam plus a gram-positive agent. The practical answer here is meropenem, weight-dosed, confirmed with pharmacy.
- Give the first dose in a monitored area with resuscitation equipment available. Do not delay it for an allergy consult or a formal cross-reactivity workup; update the allergy record afterwards.
When to add vancomycin
- Suspected catheter-related infection (erythema, tenderness, purulence at the port site, or a positive culture drawn before).
- Severe mucositis, skin or soft tissue infection, or known MRSA colonisation.
- Haemodynamic instability or a septic appearance.
- Mild mucositis alone is weak grounds; reassess after cultures and clinical course.
Reasoning. The safest answer balances allergy risk against the far greater risk of untreated gram-negative sepsis, and it keeps the timing target intact.
3. At two hours the temperature is 38.7 °C, HR 168, BP 82/48, capillary refill 4 seconds, and she is lethargic. What is your response?
Read the worked answer
Recognise septic shock. Tachycardia, narrow pulse pressure and delayed capillary refill with lethargy are decompensation, not a 'fever spike'.
Actions
- Call for help and the physician; do not leave the bedside. Apply oxygen.
- Rapid isotonic crystalloid bolus of 10–20 mL/kg, reassess after each bolus, and repeat as needed while watching for hepatomegaly, crackles and worsening work of breathing.
- Obtain a repeat lactate, glucose and calcium; ensure cultures were taken.
- Add vancomycin now - instability is an indication.
- Escalate to PICU and start a vasoactive infusion (epinephrine for cold shock) through a pump; consider stress-dose hydrocortisone for catecholamine-resistant shock after discussion with the intensivist.
- Recheck the clock: when was the first antibiotic dose actually given? Give the next dose on schedule.
Reflection for practice. In neutropenic fever, the earliest sign of shock is often a rising heart rate and a change in behaviour. The judgement being tested is escalating at the first hint of poor perfusion rather than waiting for hypotension.